This document discusses whether transposition of the great arteries (TGA) is a laterality defect associated with heterotaxy syndromes or an outflow tract malformation. It provides background on TGA, definitions of heterotaxy, and the embryonic development of the cardiac outflow tract. Recent genetic data suggests TGA may be linked to laterality gene defects, rather than outflow tract gene defects. However, the aim of the study is to determine if there is a statistically significant association between TGA and clinically diagnosed laterality defects through analysis of over 500 TGA patient cases.
Transposition of the great arteries is a serious but rare heart defect present at birth (congenital), in which the two main arteries leaving the heart are reversed (transposed). The condition is also called dextro-transposition of the great arteries.
The document discusses congenital heart disease, specifically transposition of the great arteries (TGA). TGA is a serious defect where the two main arteries leaving the heart (the aorta and pulmonary artery) are switched, or transposed. It occurs in about 1 in 4,000-5,000 births. Babies with TGA appear blue and have trouble breathing due to the lack of oxygen in their blood. Imaging like chest x-rays can help diagnose TGA by showing the reversed positioning of the heart arteries. The long term outcomes of TGA require medical management with prostaglandins or surgical repairs like arterial switches.
Transposition of Great Arteries;TGA,Firas Aljanadi,MDFIRAS ALJANADI
This document provides information on complete transposition of the great arteries (TGA), a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle. Key points include:
- TGA accounts for 9.9% of congenital heart disease in infants. Untreated, 90% of children with intact ventricular septum will die by age 1.
- Diagnosis can be made via echocardiogram which can define anatomy and flow directions. Catheterization may be needed for unclear cases.
- Primary treatments include arterial switch operation for intact septum or small VSD. Balloon septostomy can stabilize patients before repair. Pul
Transposition of the Great Arteries (TGA) is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle, resulting in parallel pulmonary and systemic circulations. This causes oxygenated and deoxygenated blood to recirculate without mixing. For survival, a communication such as a VSD or PDA is needed for blood mixing. TGA is typically diagnosed after birth by echocardiogram and treated with prostaglandins, balloon atrial septostomy, and arterial switch operation in the first month of life, with excellent long-term survival outcomes post-surgery.
This document discusses the history, diagnosis, and treatment of transposition of the great arteries (TGA). It notes that TGA is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery from the left ventricle. The document outlines the key developments in the surgical treatment of TGA, from early septostomies and shunts to the arterial switch procedure. It also describes the clinical presentation and management of different variations of TGA.
This document discusses the management of complete transposition of the great arteries (TGA). It describes palliative procedures like atrial septostomy and shunts that can be used. It also discusses the two main corrective surgeries - the arterial switch operation and atrial switch (Mustard/Senning) repairs. Complications of the atrial switch procedure include residual shunts, caval/pulmonary vein obstructions, arrhythmias, and right ventricular dysfunction. Long term survival is around 85-90% following corrective surgery.
This document discusses the anatomy, pathophysiology, and clinical presentation of transposition of the great arteries (TGA). Key points include:
- In TGA, the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle, compared to the normal arrangement. This results in deoxygenated and oxygenated blood mixing through a ventricular septal defect or patent ductus arteriosus.
- Survival without treatment is poor, particularly for those with an intact ventricular septum. Common associated anomalies include ventricular septal defects. Long term complications include pulmonary vascular disease and left ventricular outflow tract obstruction.
- The document provides detailed descriptions of the anatomical variations and abnormalities
1. Congenitally corrected transposition of the great arteries (cc-TGA) involves atrioventricular and ventriculoarterial discordance.
2. Patients often present with ventricular septal defects, heart block, or ventricular dysfunction. The risk of complete heart block increases by 2% each year.
3. Surgical options include repair of associated defects while maintaining discordance, or an anatomic repair to place the morphological left ventricle as the systemic ventricle. The approach depends on the severity of lesions and individual patient factors.
Transposition of the great arteries is a serious but rare heart defect present at birth (congenital), in which the two main arteries leaving the heart are reversed (transposed). The condition is also called dextro-transposition of the great arteries.
The document discusses congenital heart disease, specifically transposition of the great arteries (TGA). TGA is a serious defect where the two main arteries leaving the heart (the aorta and pulmonary artery) are switched, or transposed. It occurs in about 1 in 4,000-5,000 births. Babies with TGA appear blue and have trouble breathing due to the lack of oxygen in their blood. Imaging like chest x-rays can help diagnose TGA by showing the reversed positioning of the heart arteries. The long term outcomes of TGA require medical management with prostaglandins or surgical repairs like arterial switches.
Transposition of Great Arteries;TGA,Firas Aljanadi,MDFIRAS ALJANADI
This document provides information on complete transposition of the great arteries (TGA), a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle. Key points include:
- TGA accounts for 9.9% of congenital heart disease in infants. Untreated, 90% of children with intact ventricular septum will die by age 1.
- Diagnosis can be made via echocardiogram which can define anatomy and flow directions. Catheterization may be needed for unclear cases.
- Primary treatments include arterial switch operation for intact septum or small VSD. Balloon septostomy can stabilize patients before repair. Pul
Transposition of the Great Arteries (TGA) is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle, resulting in parallel pulmonary and systemic circulations. This causes oxygenated and deoxygenated blood to recirculate without mixing. For survival, a communication such as a VSD or PDA is needed for blood mixing. TGA is typically diagnosed after birth by echocardiogram and treated with prostaglandins, balloon atrial septostomy, and arterial switch operation in the first month of life, with excellent long-term survival outcomes post-surgery.
This document discusses the history, diagnosis, and treatment of transposition of the great arteries (TGA). It notes that TGA is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery from the left ventricle. The document outlines the key developments in the surgical treatment of TGA, from early septostomies and shunts to the arterial switch procedure. It also describes the clinical presentation and management of different variations of TGA.
This document discusses the management of complete transposition of the great arteries (TGA). It describes palliative procedures like atrial septostomy and shunts that can be used. It also discusses the two main corrective surgeries - the arterial switch operation and atrial switch (Mustard/Senning) repairs. Complications of the atrial switch procedure include residual shunts, caval/pulmonary vein obstructions, arrhythmias, and right ventricular dysfunction. Long term survival is around 85-90% following corrective surgery.
This document discusses the anatomy, pathophysiology, and clinical presentation of transposition of the great arteries (TGA). Key points include:
- In TGA, the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle, compared to the normal arrangement. This results in deoxygenated and oxygenated blood mixing through a ventricular septal defect or patent ductus arteriosus.
- Survival without treatment is poor, particularly for those with an intact ventricular septum. Common associated anomalies include ventricular septal defects. Long term complications include pulmonary vascular disease and left ventricular outflow tract obstruction.
- The document provides detailed descriptions of the anatomical variations and abnormalities
1. Congenitally corrected transposition of the great arteries (cc-TGA) involves atrioventricular and ventriculoarterial discordance.
2. Patients often present with ventricular septal defects, heart block, or ventricular dysfunction. The risk of complete heart block increases by 2% each year.
3. Surgical options include repair of associated defects while maintaining discordance, or an anatomic repair to place the morphological left ventricle as the systemic ventricle. The approach depends on the severity of lesions and individual patient factors.
Congenitally corrected transposition of the great arteries (CC TGA) is a rare congenital heart defect where the ventricles are connected abnormally at the atrioventricular and ventriculoarterial junctions, physiologically correcting the discordance. It typically presents with other defects like ventricular septal defects and pulmonary stenosis. Surgical repair focuses on closing ventricular septal defects and treating pulmonary stenosis or tricuspid valve issues, but carries risks of heart block and low survival rates long term.
D-Transposition, also known as dextro-Transposition of the great arteries (d-TGA), is a congenital heart defect where the ventricles are connected to the wrong great arteries. Specifically, the aorta arises from the right ventricle while the pulmonary artery arises from the left ventricle. This causes two parallel circulations instead of the normal series circulation. The basic embryological defect is abnormal development of the conus, which prevents normal septal formation between the great arteries. Untreated d-TGA is fatal in infancy due to lack of oxygenated blood to the body. Clinical presentation depends on the degree of mixing between the circulations.
Congenitally corrected transposition of great arteriesDheeraj Sharma
This document provides an overview of congenitally corrected transposition of the great arteries (CCTGA). Key points include:
- CCTGA is a rare congenital heart defect where the ventricles are transposed but the atria are connected to the physically opposite ventricles, resulting in circulatory pathways in series.
- Patients may be asymptomatic for years but eventually develop right ventricular failure or left ventricular outflow tract obstruction. Diagnosis is made through physical exam, chest x-ray, and electrocardiogram showing right ventricular hypertrophy.
- Associated anomalies include ventricular septal defects, pulmonary stenosis, Ebstein's anomaly of the tricuspid valve, and heart block. Surgical
Transposition of the great arteries (TGA) is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle, causing parallel instead of serial circulation. TGA accounts for 5-7% of congenital heart diseases and has an annual incidence of 20-30 per 100,000 live births. Without treatment, TGA is incompatible with long-term survival due to lack of oxygen supply. Initial treatment involves prostaglandin E1 to maintain ductal patency and increase pulmonary blood flow. Later procedures include the Rastelli operation or arterial switch operation to correct the defect.
1. Transposition of the great arteries (TGA) is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle.
2. TGA has an incidence of 5-7% of all congenital heart defects and is usually an isolated defect in 90% of cases.
3. After birth, mixing of saturated and unsaturated blood cannot occur properly due to the unsuitable ventricular-arterial connections, leading to hypoxemia.
1) Complete transposition of the great arteries (d-TGA) is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle, causing ventriculoarterial discordance.
2) In d-TGA, the systemic and pulmonary circulations are arranged in parallel rather than in series, requiring blood flow between the circuits through connections like an atrial or ventricular septal defect.
3) Echocardiography is useful for diagnosing d-TGA by demonstrating the aorta originating from the right ventricle and pulmonary artery from the left ventricle, as well as identifying the origins of the coronary arteries.
- L-TGA, also known as corrected transposition of the great arteries, is a rare congenital heart defect where the ventricles are transposed and the atrioventricular valves are discordant.
- The embryological cause is abnormal leftward looping of the heart during development, resulting in the morphologic right ventricle being on the left side and pumping blood to the lungs, while the morphologic left ventricle is on the right side and pumps blood to the body.
- Associated abnormalities are common, including ventricular septal defects, pulmonary stenosis, tricuspid valve anomalies, and conduction system abnormalities. Long term, the right ventricle is poorly suited to function as the systemic
This document discusses the anatomy, embryology, and management of L-TGA (transposition of the great arteries). Some key points:
- In L-TGA, the ventricles are inverted such that the morphologic right ventricle is on the left and pumps blood to the lungs, while the morphologic left ventricle is on the right and pumps blood to the body.
- Embryologically, abnormal leftward looping of the heart tube during development results in the inverted ventricles. The conduction system and coronary arteries also have abnormal anatomy.
- Clinical features may include congenital heart block, progressive tricuspid regurgitation, pulmonary stenosis, and heart failure. Diagn
This document provides information on transposition of the great arteries (TGA), including its definition, theories of development, morphology, clinical features, diagnosis, and management. Some key points:
- TGA is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle, rather than their normal positions.
- There are several theories for its development during embryogenesis. Its morphology involves abnormalities in the ventricles, arteries, valves, and other structures compared to normal.
- Presentation depends on mixing between circulations. Poor mixing in infants with intact septum leads to severe cyanosis. Better mixing with a VSD or P
Transposition of the great arteries is a congenital heart defect where the two main arteries that carry blood away from the heart - the pulmonary artery and the aorta - are switched. This results in deoxygenated blood being pumped to the body and oxygenated blood being pumped to the lungs. While transposition of the great arteries was first described centuries ago, no treatment was available until the 1950s with the development of surgical procedures. Today, survival rates following surgical repair exceed 90%.
This document discusses coronary artery anomalies associated with congenital heart disease. It notes that coronary anomalies can be associated with or due to congenital heart diseases like tetralogy of Fallot, transposition of the great arteries, truncus arteriosus, and pulmonary atresia with intact ventricular septum. It provides details on common coronary artery patterns and surgical management options for addressing anomalous coronary arteries during repair of various congenital heart defects.
This document provides an overview of complete transposition of the great arteries (TGA), including its definition, history, morphology, associated conditions, and theories of development. TGA is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle. The document discusses the early descriptions and surgical treatments of TGA. It provides detailed information on the anatomy and variations that can occur in TGA. Associated conditions include ventricular septal defects and left ventricular outflow tract obstruction.
This presentation talks about the ventricular septal defect definition, incidence rate, Genetics, morphology, physiology, classification, investigations and management
Truncus arteriosus is a rare congenital heart defect where a single arterial trunk arises from the heart to supply the pulmonary and systemic circulations. It occurs when the embryonic truncus arteriosus fails to divide into the aorta and pulmonary artery. Left untreated, it causes cyanosis and heart failure in newborns. Surgical repair is now possible to connect the pulmonary artery to the right ventricle, improving survival rates to over 80% at one year of age compared to just 15% for uncorrected patients.
This document discusses various types of single ventricle heart defects where there is only one functioning ventricle pumping blood to both the lungs and body. It describes the different terms used to describe these hearts including single ventricle, univentricular heart, and double inlet ventricle. The most common type is double inlet left ventricle where both atria connect to a dominant left ventricle. Other types include double inlet right ventricle, absent atrioventricular connections, and a common atrioventricular valve. The document outlines the challenges these hearts face in maintaining adequate blood flow and oxygen levels to both circulations.
TGA is a complex congenital heart disease.Understanding the anatomy,physiology,surgery and anaesthetic management is very important for patient's better outcome.This ppt explains all these points in detail.
TAPVC defines the anomaly in which the pulmonary veins have no connection with the left atrium. Rather, the pulmonary veins connect directly to one of the systemic veins (TAPVC) or drain in to right atrium.
A PFO or ASD is present essentially in those who survive after birth
When pulmonary veins drain anomalously into the right atrium either because of complete absence of the interatrial septum or malattachment of the septum primum , then it is known as total anomalous pulmonary venous drainage.
When some or all of the pulmonary veins drain anomalously in to RA or its tributaries without being abnormally connected, the terms partially anomalous pulmonary venous drainage (PAPVD) or totally anomalous pulmonary venous drainage (TAPVD) with normal pulmonary venous connections are used.
Surgical management of d-tga Dr. ankit jain AIIMSAnkit Jain
This document provides information on the surgical management of transposition of the great arteries (TGA). It discusses the history, embryology, associated lesions, and surgical techniques for TGA. Some key points include:
- TGA accounts for 5-7% of congenital heart defects and was first described in 1797.
- The most accepted embryological theory is abnormal development of the bilateral subarterial conus.
- Associated lesions include VSD, LVOT obstruction, and aortic arch anomalies.
- Surgical techniques have evolved from atrial septectomy in the 1950s to the arterial switch operation (ASO) developed in 1975, which has high survival rates of over 98% today.
Segmental approach to Congenital Heart DiseaseTanat Tabtieang
The document describes the Van Praagh classification system for congenital heart disease, which uses a three-part notation to describe the visceroatrial situs, ventricular loop orientation, and great vessel arrangement. It first reviews related embryology, then outlines the three steps of the classification system: 1) determining the visceroatrial situs as situs solitus, situs inversus, or situs ambiguus, 2) assessing the ventricular loop orientation, and 3) evaluating the position and relationship of the great vessels. Key anatomic features are described to identify each component of the classification.
Fetal Vascular Rings: Beyond The Anomalies of The Aortic Archpateldrona
Different anomalies related to the inappropriate development of the ductus arteriosus or the aortic arch have been described, in some cases accompanied with chromosomal or morphological anomalies, and also being able to form a vascular ring that can compromise the postnatal life
Fetal Vascular Rings: Beyond The Anomalies of The Aortic Archnavasreni
Different anomalies related to the inappropriate development of the ductus arteriosus or the aortic arch have been described, in some cases accompanied with chromosomal or morphological anomalies, and also being able to form a vascular ring that can compromise the postnatal life.
Fetal Vascular Rings: Beyond The Anomalies of The Aortic Archkomalicarol
Different anomalies related to the inappropriate development of the ductus arteriosus or the
aortic arch have been described, in some cases accompanied with chromosomal or morphological anomalies, and also being able to form a vascular ring that can compromise the postnatal life. For this reason, a complete fetal anatomy examination and cardiovascular study is
needed to discard possible other malformations or ultrasound markers for fetal syndromes. A
detailed prenatal diagnosis of the type of ductal arch anomaly and possible vascular ring can
give us a postnatal prognosis and help pediatricians with the management of symptomatic
neonates
Congenitally corrected transposition of the great arteries (CC TGA) is a rare congenital heart defect where the ventricles are connected abnormally at the atrioventricular and ventriculoarterial junctions, physiologically correcting the discordance. It typically presents with other defects like ventricular septal defects and pulmonary stenosis. Surgical repair focuses on closing ventricular septal defects and treating pulmonary stenosis or tricuspid valve issues, but carries risks of heart block and low survival rates long term.
D-Transposition, also known as dextro-Transposition of the great arteries (d-TGA), is a congenital heart defect where the ventricles are connected to the wrong great arteries. Specifically, the aorta arises from the right ventricle while the pulmonary artery arises from the left ventricle. This causes two parallel circulations instead of the normal series circulation. The basic embryological defect is abnormal development of the conus, which prevents normal septal formation between the great arteries. Untreated d-TGA is fatal in infancy due to lack of oxygenated blood to the body. Clinical presentation depends on the degree of mixing between the circulations.
Congenitally corrected transposition of great arteriesDheeraj Sharma
This document provides an overview of congenitally corrected transposition of the great arteries (CCTGA). Key points include:
- CCTGA is a rare congenital heart defect where the ventricles are transposed but the atria are connected to the physically opposite ventricles, resulting in circulatory pathways in series.
- Patients may be asymptomatic for years but eventually develop right ventricular failure or left ventricular outflow tract obstruction. Diagnosis is made through physical exam, chest x-ray, and electrocardiogram showing right ventricular hypertrophy.
- Associated anomalies include ventricular septal defects, pulmonary stenosis, Ebstein's anomaly of the tricuspid valve, and heart block. Surgical
Transposition of the great arteries (TGA) is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle, causing parallel instead of serial circulation. TGA accounts for 5-7% of congenital heart diseases and has an annual incidence of 20-30 per 100,000 live births. Without treatment, TGA is incompatible with long-term survival due to lack of oxygen supply. Initial treatment involves prostaglandin E1 to maintain ductal patency and increase pulmonary blood flow. Later procedures include the Rastelli operation or arterial switch operation to correct the defect.
1. Transposition of the great arteries (TGA) is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle.
2. TGA has an incidence of 5-7% of all congenital heart defects and is usually an isolated defect in 90% of cases.
3. After birth, mixing of saturated and unsaturated blood cannot occur properly due to the unsuitable ventricular-arterial connections, leading to hypoxemia.
1) Complete transposition of the great arteries (d-TGA) is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle, causing ventriculoarterial discordance.
2) In d-TGA, the systemic and pulmonary circulations are arranged in parallel rather than in series, requiring blood flow between the circuits through connections like an atrial or ventricular septal defect.
3) Echocardiography is useful for diagnosing d-TGA by demonstrating the aorta originating from the right ventricle and pulmonary artery from the left ventricle, as well as identifying the origins of the coronary arteries.
- L-TGA, also known as corrected transposition of the great arteries, is a rare congenital heart defect where the ventricles are transposed and the atrioventricular valves are discordant.
- The embryological cause is abnormal leftward looping of the heart during development, resulting in the morphologic right ventricle being on the left side and pumping blood to the lungs, while the morphologic left ventricle is on the right side and pumps blood to the body.
- Associated abnormalities are common, including ventricular septal defects, pulmonary stenosis, tricuspid valve anomalies, and conduction system abnormalities. Long term, the right ventricle is poorly suited to function as the systemic
This document discusses the anatomy, embryology, and management of L-TGA (transposition of the great arteries). Some key points:
- In L-TGA, the ventricles are inverted such that the morphologic right ventricle is on the left and pumps blood to the lungs, while the morphologic left ventricle is on the right and pumps blood to the body.
- Embryologically, abnormal leftward looping of the heart tube during development results in the inverted ventricles. The conduction system and coronary arteries also have abnormal anatomy.
- Clinical features may include congenital heart block, progressive tricuspid regurgitation, pulmonary stenosis, and heart failure. Diagn
This document provides information on transposition of the great arteries (TGA), including its definition, theories of development, morphology, clinical features, diagnosis, and management. Some key points:
- TGA is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle, rather than their normal positions.
- There are several theories for its development during embryogenesis. Its morphology involves abnormalities in the ventricles, arteries, valves, and other structures compared to normal.
- Presentation depends on mixing between circulations. Poor mixing in infants with intact septum leads to severe cyanosis. Better mixing with a VSD or P
Transposition of the great arteries is a congenital heart defect where the two main arteries that carry blood away from the heart - the pulmonary artery and the aorta - are switched. This results in deoxygenated blood being pumped to the body and oxygenated blood being pumped to the lungs. While transposition of the great arteries was first described centuries ago, no treatment was available until the 1950s with the development of surgical procedures. Today, survival rates following surgical repair exceed 90%.
This document discusses coronary artery anomalies associated with congenital heart disease. It notes that coronary anomalies can be associated with or due to congenital heart diseases like tetralogy of Fallot, transposition of the great arteries, truncus arteriosus, and pulmonary atresia with intact ventricular septum. It provides details on common coronary artery patterns and surgical management options for addressing anomalous coronary arteries during repair of various congenital heart defects.
This document provides an overview of complete transposition of the great arteries (TGA), including its definition, history, morphology, associated conditions, and theories of development. TGA is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle. The document discusses the early descriptions and surgical treatments of TGA. It provides detailed information on the anatomy and variations that can occur in TGA. Associated conditions include ventricular septal defects and left ventricular outflow tract obstruction.
This presentation talks about the ventricular septal defect definition, incidence rate, Genetics, morphology, physiology, classification, investigations and management
Truncus arteriosus is a rare congenital heart defect where a single arterial trunk arises from the heart to supply the pulmonary and systemic circulations. It occurs when the embryonic truncus arteriosus fails to divide into the aorta and pulmonary artery. Left untreated, it causes cyanosis and heart failure in newborns. Surgical repair is now possible to connect the pulmonary artery to the right ventricle, improving survival rates to over 80% at one year of age compared to just 15% for uncorrected patients.
This document discusses various types of single ventricle heart defects where there is only one functioning ventricle pumping blood to both the lungs and body. It describes the different terms used to describe these hearts including single ventricle, univentricular heart, and double inlet ventricle. The most common type is double inlet left ventricle where both atria connect to a dominant left ventricle. Other types include double inlet right ventricle, absent atrioventricular connections, and a common atrioventricular valve. The document outlines the challenges these hearts face in maintaining adequate blood flow and oxygen levels to both circulations.
TGA is a complex congenital heart disease.Understanding the anatomy,physiology,surgery and anaesthetic management is very important for patient's better outcome.This ppt explains all these points in detail.
TAPVC defines the anomaly in which the pulmonary veins have no connection with the left atrium. Rather, the pulmonary veins connect directly to one of the systemic veins (TAPVC) or drain in to right atrium.
A PFO or ASD is present essentially in those who survive after birth
When pulmonary veins drain anomalously into the right atrium either because of complete absence of the interatrial septum or malattachment of the septum primum , then it is known as total anomalous pulmonary venous drainage.
When some or all of the pulmonary veins drain anomalously in to RA or its tributaries without being abnormally connected, the terms partially anomalous pulmonary venous drainage (PAPVD) or totally anomalous pulmonary venous drainage (TAPVD) with normal pulmonary venous connections are used.
Surgical management of d-tga Dr. ankit jain AIIMSAnkit Jain
This document provides information on the surgical management of transposition of the great arteries (TGA). It discusses the history, embryology, associated lesions, and surgical techniques for TGA. Some key points include:
- TGA accounts for 5-7% of congenital heart defects and was first described in 1797.
- The most accepted embryological theory is abnormal development of the bilateral subarterial conus.
- Associated lesions include VSD, LVOT obstruction, and aortic arch anomalies.
- Surgical techniques have evolved from atrial septectomy in the 1950s to the arterial switch operation (ASO) developed in 1975, which has high survival rates of over 98% today.
Segmental approach to Congenital Heart DiseaseTanat Tabtieang
The document describes the Van Praagh classification system for congenital heart disease, which uses a three-part notation to describe the visceroatrial situs, ventricular loop orientation, and great vessel arrangement. It first reviews related embryology, then outlines the three steps of the classification system: 1) determining the visceroatrial situs as situs solitus, situs inversus, or situs ambiguus, 2) assessing the ventricular loop orientation, and 3) evaluating the position and relationship of the great vessels. Key anatomic features are described to identify each component of the classification.
Fetal Vascular Rings: Beyond The Anomalies of The Aortic Archpateldrona
Different anomalies related to the inappropriate development of the ductus arteriosus or the aortic arch have been described, in some cases accompanied with chromosomal or morphological anomalies, and also being able to form a vascular ring that can compromise the postnatal life
Fetal Vascular Rings: Beyond The Anomalies of The Aortic Archnavasreni
Different anomalies related to the inappropriate development of the ductus arteriosus or the aortic arch have been described, in some cases accompanied with chromosomal or morphological anomalies, and also being able to form a vascular ring that can compromise the postnatal life.
Fetal Vascular Rings: Beyond The Anomalies of The Aortic Archkomalicarol
Different anomalies related to the inappropriate development of the ductus arteriosus or the
aortic arch have been described, in some cases accompanied with chromosomal or morphological anomalies, and also being able to form a vascular ring that can compromise the postnatal life. For this reason, a complete fetal anatomy examination and cardiovascular study is
needed to discard possible other malformations or ultrasound markers for fetal syndromes. A
detailed prenatal diagnosis of the type of ductal arch anomaly and possible vascular ring can
give us a postnatal prognosis and help pediatricians with the management of symptomatic
neonates
Fetal Vascular Rings: Beyond The Anomalies of The Aortic ArchSarkarRenon
Different anomalies related to the inappropriate development of the ductus arteriosus or the aortic arch have been described, in some cases accompanied with chromosomal or morphological anomalies, and also being able to form a vascular ring that can compromise the postnatal life.
Fetal Vascular Rings: Beyond The Anomalies of The Aortic ArchAnonIshanvi
Different anomalies related to the inappropriate development of the ductus arteriosus or the aortic arch have been described, in some cases accompanied with chromosomal or morphological anomalies, and also being able to form a vascular ring that can compromise the postnatal life.
Fetal Vascular Rings: Beyond The Anomalies of The Aortic Archgeorgemarini
Different anomalies related to the inappropriate development of the ductus arteriosus or the aortic arch have been described, in some cases accompanied with chromosomal or morphological anomalies, and also being able to form a vascular ring that can compromise the postnatal life
This study aimed to identify a new echocardiographic index to detect coarctation of the aorta in neonates and infants. The researchers measured dimensions of the aortic arch in 63 patients with coarctation and 23 controls. They found that while ascending and descending aorta diameters were similar, the transverse arch was smaller in patients. Distances between great vessel origins were longer in patients than controls. The ratio of the subclavian artery diameter to the distance between the carotid and subclavian arteries, termed the carotid-subclavian artery index, was significantly smaller in patients. Using a cutoff of 1.5, the index showed high sensitivity and specificity for detecting coarctation in neonates and infants.
Functional echocardiography in the fetus with non cardiac diseasegisa_legal
This document discusses how functional echocardiography can assess fetal cardiac function in fetuses with non-cardiac diseases or conditions that impact the fetus. It provides an overview of normal fetal cardiovascular physiology and describes various ultrasound methods for evaluating fetal cardiac output, size, function, and hemodynamics. A major focus is on how these methods have helped understand the cardiovascular changes seen in fetuses with intrauterine growth restriction (IUGR). In IUGR, the fetus initially maintains cardiac output while preferentially shunting blood to the heart and brain via changes in ductus venosus and cerebral blood flow. Over time, myocardial dysfunction occurs and the right ventricle assumes more output as placental resistance increases. This can progress
Functional echocardiography in the fetus with non cardiac diseasegisa_legal
This document discusses the use of functional echocardiography to assess fetal cardiac function in fetuses with non-cardiac diseases or conditions that pose hemodynamic challenges. It reviews how various extrauterine factors can impact fetal cardiac function and outlines techniques like measuring cardiac output, ventricular size, and indices of systolic and diastolic function that can help evaluate the fetal heart's adaptation. Assessing cardiac function can provide insights into disease progression and help guide management decisions, particularly in more severe cases where delivery timing may need to be optimized.
1) The study compared systemic right ventricular function in unoperated and physiologically repaired congenitally corrected transposition of the great arteries (CCTGA) patients to healthy controls, using MRI dobutamine stress testing.
2) At baseline, systemic right ventricular volumes were larger but ejection fraction was lower in CCTGA patients compared to controls. However, all groups responded appropriately to dobutamine stress with increases in stroke volume and cardiac index.
3) While CCTGA patients had diminished ejection fraction at baseline compared to controls, their systemic right ventricle responded similarly to dobutamine stress, suggesting preserved cardiac reserve. MRI dobutamine stress may help identify CCTGA patients who can be observed without operation.
A 38-year-old male farmer presented with progressive shortness of breath and fatigue. Echocardiography revealed severe mitral stenosis and a large secundum atrial septal defect, consistent with the rare Lutembacher syndrome. Despite treatment, the patient died two days after admission, illustrating the poor prognosis when this syndrome is identified late in low-resource settings without access to surgical or percutaneous interventions. Lutembacher syndrome refers to the uncommon combination of mitral stenosis and atrial septal defect, which can lead to pulmonary hypertension and heart failure if not treated early through surgery or catheter procedures.
Cardiac emergencies in the first year of lifesxbenavides
This document discusses cardiac emergencies that may present in infants in the first year of life. It describes the most common cyanotic congenital heart lesions which cause central cyanosis, including Tetralogy of Fallot, Transposition of the Great Arteries, Tricuspid Atresia, Total Anomalous Pulmonary Venous Return, and Truncus Arteriosus. For each condition, it outlines the pathophysiology, typical presentation, physical exam findings, ECG and chest x-ray characteristics. It also discusses cyanosis, cyanotic heart disease, and the transition of cardiovascular physiology at birth.
This document discusses how functional echocardiography can assess cardiac function in fetuses with non-cardiac diseases or conditions that impact the fetus. It provides details on:
1) How ultrasound can evaluate various aspects of fetal cardiac function like cardiac output, size, contractility, and diastolic function.
2) Examples of conditions that can alter fetal hemodynamics like intrauterine growth restriction (IUGR), tumors, twin-twin transfusion syndrome, and maternal diabetes. In IUGR, changes in the umbilical artery and ductus venosus occur as placental function declines.
3) Insights from evaluating these conditions, such as how IUGR fetuses develop a dominant left
The document discusses imaging of congenital heart diseases, describing the main types of defects such as atrial septal defects (ASD), ventricular septal defects (VSD), and patent ductus arteriosus (PDA). It provides details on the anatomy, classifications, imaging findings, and clinical presentations of each type of defect. Examples of echocardiograms and chest x-rays are shown to illustrate the imaging appearance of various congenital heart abnormalities.
Anesthesia And Congenital Heart DiseaseAhmed Shalabi
This document summarizes adult congenital heart disease and considerations for anesthesia management. It discusses that:
1) Congenital heart diseases are increasingly common as more children with complex defects now survive into adulthood.
2) Adults with CHD can be categorized as those with complete repair, partial/palliative repair, or no operation.
3) Five factors influence perioperative risk - pulmonary hypertension, cyanosis, reoperation, arrhythmias, and ventricular dysfunction.
This study examined echocardiographic predictors of perinatal mortality in fetuses diagnosed with Ebstein's anomaly or tricuspid valve dysplasia. The study reviewed 21 fetuses between 2000-2008. Smaller right atrial size and absence of hydrops were associated with improved survival. Analysis of left ventricular function showed non-survivors had shorter combined contraction and relaxation times, though ejection times did not differ. Overall perinatal survival was 75% and survival to 3 months was 57-50% depending on whether terminations were included.
This document describes a case report of a 70-year-old man found to have a giant left atrial myxoma, which is a rare type of heart tumor. Trans-thoracic echocardiography revealed a large irregular mass occupying the entire left atrium. The patient underwent successful surgical excision of the mass. Pathological examination confirmed it was a left atrial myxoma measuring 7.5 x 4.5 x 2.5 cm. Follow-up echocardiography showed no remaining tumor and normal heart function. While rare in the elderly, left atrial myxomas should be considered as a potential cause of cardiac symptoms even in older patients.
This document provides an overview of congenital obstructive lesions that may be seen in adults, including:
1) Congenital obstructive lesions increase ventricular afterload and can cause ventricular hypertrophy, reduced compliance, and higher filling pressures. Symptoms are generally related to the severity of obstruction.
2) Common obstructive lesions include subvalvar, valvar, and supravalvar pulmonary stenosis. Severe obstructions can cause right ventricular dysfunction, arrhythmias, and sudden cardiac death.
3) Indications for intervention include symptoms, elevated right ventricular pressures, and reduced systolic function. Balloon valvuloplasty is now preferred over surgery for valvar pulmonary stenosis. Surgical options
This document discusses the pathophysiology of congenital heart disease, specifically focusing on shunt lesions commonly seen in adults. It describes how atrial septal defects (ASDs) allow blood to shunt between the left and right atria, usually left-to-right. The direction and amount of shunting depends on factors like ventricular compliance. Large or unrepaired ASDs in adults can cause shortness of breath, arrhythmias, or paradoxical embolism. While pulmonary hypertension is rare with ASDs, it may develop in some cases. The natural history and clinical presentations of ASDs in adults are discussed.
This document discusses the causes and evaluation of ischemic stroke in young adults. Some key causes include arterial dissection, cardiac embolism, premature atherosclerosis, hematological disorders, and migraines. A comprehensive evaluation is important since many of the underlying disorders are treatable. Evaluations may include tests of blood, imaging of blood vessels and heart, genetic testing, and other investigations tailored to the individual patient based on clinical clues. Proper management requires a specialized physician and identifying a cause can help determine risk of future strokes.
Similar to Transposition of the great arteries (20)
A 57-year-old woman was admitted to the hospital with chest pain. Electrocardiograms and troponin levels were normal. Intravascular ultrasound was performed before placing a stent in the left main coronary artery and left anterior descending artery to treat a blockage. The minimum lumen area increased to 4.24mm x 4.13mm after stenting.
Congenital defects can put a strain on the heart, causing it to work harder. To stop your heart from getting weaker with this extra work, your doctor may try to treat you with medications. They are aimed at easing the burden on the heart muscle. You need to control your blood pressure if you have any type of heart problem.
Changing your lifestyle can help control and manage high blood pressure. Your health care provider may recommend that you make lifestyle changes including:
Eating a heart-healthy diet with less salt
Getting regular physical activity
Maintaining a healthy weight or losing weight
Limiting alcohol
Not smoking
Getting 7 to 9 hours of sleep daily
CRISPR technologies have progressed by leaps and bounds over the past decade, not only having a transformative effect on
biomedical research but also yielding new therapies that are poised to enter the clinic. In this review, I give an overview of (i)
the various CRISPR DNA-editing technologies, including standard nuclease gene editing, base editing, prime editing, and epigenome editing, (ii) their impact on cardiovascular basic science research, including animal models, human pluripotent stem
cell models, and functional screens, and (iii) emerging therapeutic applications for patients with cardiovascular diseases, focusing on the examples of Hypercholesterolemia, transthyretin amyloidosis, and Duchenne muscular dystrophy.
This case report describes a patient who underwent seven operations over one year to treat recurrent pacemaker pocket infections. The patient had undergone a splenectomy seven years prior due to a splenic rupture from a traffic accident. This left the patient immunocompromised and at higher risk for infection. The patient later required a pacemaker implantation for complete heart block. The pacemaker pocket developed repeated infections, likely due to the patient's asplenic state impairing immunity. The infections were difficult to treat due to multiple complicating factors, including an abandoned pacemaker lead and reuse of a sterilized pacemaker. This highlights the influence of patient factors like asplenia on procedural outcomes like pacemaker implantation.
Transcatheter closure of patent ductus arteriosus (PDA) is feasible in low-birth-weight infants. A female baby was born prematurely with a birth weight of 924 g. She had a PDA measuring 3.7 mm. She was dependent on positive pressure ventilation for congestive heart failure in addition to the heart failure medications. She could not be discharged from the hospital even after 79 days of birth, and even though her weight reached 1.9 kg in the neonatal intensive care unit. We attempted to plug the PDA using an Amplatzer Piccolo Occluder, but the device failed to anchor. Then, the PDA was plugged using a 4-6 Amplatzer Duct Occluder using a 6-Fr sheath which was challenging.
Accidental misplacement of the limb lead electrodes is a common cause of ECG abnormality and may simulate pathology such as ectopic atrial rhythm, chamber enlargement or myocardial ischaemia and infarction
A Case of Device Closure of an Eccentric Atrial Septal Defect Using a Large D...Ramachandra Barik
Device closure of an eccentric atrial septal defect can be challenging and needs technical modifications to avoid unnecessary complications. Here, we present a case of a 45-year-old woman who underwent device closure of an eccentric defect with a large device. The patient developed pericardial effusion and left-sided pleural effusion due to injury to the junction of right atrium and superior vena cava because of the malalignment of the delivery sheath and left atrial disc before the device was pulled across the eccentric defect despite releasing the left atrial disc in the left atrium in place of the left pulmonary vein. These two serious complications were managed conservatively with close monitoring of the case during and after the procedure.
1) Bradycardia can be caused by abnormalities in the conduction system or autonomic nervous system. The conduction system includes the sinus node, AV node, His-Purkinje system and different types of heart block can occur when impulses are blocked at different locations.
2) There are three main types of AV block - first degree, second degree (Mobitz types I and II), and third degree. High grade AV block involves blockage of two or more consecutive impulses.
3) Third degree or complete heart block results in complete dissociation between the atria and ventricles with independent pacemakers. It can occur at the AV node or below in the His-Purkin
1. Bradycardia is defined as a resting heart rate below 50 beats per minute. It can be physiological or pathological.
2. Sinus bradycardia originates from the sinus node and has a normal P wave morphology with a prolonged PR interval. It can be caused by increased vagal tone, medications, or hypothyroidism.
3. Sick sinus syndrome is characterized by sinus bradycardia, sinus arrest, or combinations of sinus node and AV node dysfunction. It may involve intermittent bradycardia and tachycardia. Pacemaker implantation is usually treatment.
This document discusses ventricular arrhythmias including their origins, characteristics, classifications, and causes. It provides details on:
- The sites of origin for supraventricular tachycardia (SVT) and ventricular arrhythmias.
- Characteristics that distinguish SVT from ventricular arrhythmias such as QRS width.
- Classifications of ventricular arrhythmias including premature ventricular complexes, ventricular tachycardia, fibrillation, and electrical storm.
- Causes and characteristics of different types of ventricular tachycardia such as monomorphic VT, polymorphic VT, and torsades de pointes.
- Investigations and treatments for ventricular arrhythmias including cardiac imaging
This document provides information on supraventricular tachycardia (SVT), including:
- The anatomy and conduction system of the heart that is relevant to SVT.
- The mechanisms that can cause cardiac arrhythmias, including disorders of impulse formation, conduction, and combinations of the two.
- Characteristics used to classify different types of arrhythmias based on rate, rhythm, site of origin, and QRS morphology.
- Specific types of SVT like atrial fibrillation, AV nodal reentry tachycardia, and accessory pathway mediated tachycardias.
- Methods for diagnosing and treating SVT such as electrophysiology studies, catheter ablation
Trio of Rheumatic Mitral Stenosis, Right Posterior Septal Accessory Pathway a...Ramachandra Barik
A 57-year-old male presented with recurrent palpitations. He was diagnosed with rheumatic mitral stenosis, right posterior septal accessory pathway and atrial flutter. An electrophysiological study after percutaneous balloon mitral valvotomy showed that the palpitations were due to atrial flutter with right bundle branch aberrancy. The right posterior septal pathway was a bystander because it had a higher refractory period than the atrioventricular node.
This document discusses anticoagulation therapy options during pregnancy for different cardiac conditions. It notes that vitamin K antagonists (VKAs) should be avoided in the first trimester due to risk of embryopathy but can be used in the second and third trimester with risks of 0.7-2% of foetopathy. Unfractionated heparin does not cross the placenta but its use throughout pregnancy is not recommended due to risk of foetopathy. Low molecular weight heparin is considered the safest option for anticoagulation in weeks 6-12 when risk of embryopathy is a concern and has not been associated with risk of foetopathy. Fondaparinux use should be limited
Percutaneous balloon dilatation, first described by
Andreas Gruentzig in 1979, was initially performed
without the use of guidewires.1 The prototype
balloon catheter was developed as a double lumen
catheter (one lumen for pressure monitoring or
distal perfusion, the other lumen for balloon inflation/deflation) with a short fixed and atraumatic
guidewire at the tip. Indeed, initially the technique
involved advancing a rather rigid balloon catheter
freely without much torque control into a coronary
artery. Bends, tortuosities, angulations, bifurcations,
and eccentric lesions could hardly, if at all, be negotiated, resulting in a rather frustrating low procedural success rate whenever the initial limited
indications (proximal, short, concentric, noncalcified) were negated.2 Luck was almost as
important as expertise, not only for the operator,
but also for the patient. It is to the merit of
Simpson who, in 1982, introduced the novelty of
advancing the balloon catheter over a removable
guidewire, which had first been advanced in the
target vessel.3 This major technical improvement
resulted overnight in a notable increase in the procedural success rate. Guidewires have since evolved
into very sophisticated devices.
Optical coherence tomography-guided algorithm for percutaneous coronary intervention. Vessel diameter should be assessed using the external elastic lamina (EEL)-EEL diameter at the reference segments, and rounded down to select interventional devices (balloons, stents). If the EEL cannot be identified, luminal measures are used and rounded up to 0.5 mm larger for selection of the devices. Optical coherence tomography (OCT)-guided optimisation strategies post stent implantation per EEL-based diameter measurement and per lumen-based diameter measurement are shown. For instance, if the distal EEL-EEL diameter measures 3.2 mm×3.1 mm (i.e., the mean EEL-based diameter is 3.15 mm), this number is rounded down to the next available stent size and post-dilation balloon to be used at the distal segment. Thus, a 3.0 mm stent and non-compliant balloon diameter is selected. If the proximal EEL cannot be visualised, the mean lumen diameter should be used for device sizing. For instance, if the mean proximal lumen diameter measures 3.4 mm, this number is rounded up to the next available balloon diameter (within up to 0.5 mm larger) for post-dilation. MLA: minimal lumen area; MSA: minimal stent area;NC: non-compliant
Brugada syndrome (BrS) is an inherited cardiac disorder,
characterised by a typical ECG pattern and an increased
risk of arrhythmias and sudden cardiac death (SCD).
BrS is a challenging entity, in regard to diagnosis as
well as arrhythmia risk prediction and management.
Nowadays, asymptomatic patients represent the majority
of newly diagnosed patients with BrS, and its incidence
is expected to rise due to (genetic) family screening.
Progress in our understanding of the genetic and
molecular pathophysiology is limited by the absence
of a true gold standard, with consensus on its clinical
definition changing over time. Nevertheless, novel
insights continue to arise from detailed and in-depth
studies, including the complex genetic and molecular
basis. This includes the increasingly recognised
relevance of an underlying structural substrate. Risk
stratification in patients with BrS remains challenging,
particularly in those who are asymptomatic, but recent
studies have demonstrated the potential usefulness
of risk scores to identify patients at high risk of
arrhythmia and SCD. Development and validation of
a model that incorporates clinical and genetic factors,
comorbidities, age and gender, and environmental
aspects may facilitate improved prediction of disease
expressivity and arrhythmia/SCD risk, and potentially
guide patient management and therapy. This review
provides an update of the diagnosis, pathophysiology
and management of BrS, and discusses its future
perspectives.
The Human Developmental Cell Atlas (HDCA) initiative, which is part of the Human Cell Atlas, aims to create a comprehensive reference map of cells during development. This will be critical to understanding normal organogenesis, the effect of mutations, environmental factors and infectious agents on human development, congenital and childhood disorders, and the cellular basis of ageing, cancer and regenerative medicine. Here we outline the HDCA initiative and the challenges of mapping and modelling human development using state-of-the-art technologies to create a reference atlas across gestation. Similar to the Human Genome Project, the HDCA will integrate the output from a growing community of scientists who are mapping human development into a unified atlas. We describe the early milestones that have been achieved and the use of human stem-cell-derived cultures, organoids and animal models to inform the HDCA, especially for prenatal tissues that are hard to acquire. Finally, we provide a roadmap towards a complete atlas of human development.
The treatment of patients with advanced acute heart failure is still challenging.
Intra-aortic balloon pump (IABP) has widely been used in the management of
patients with cardiogenic shock. However, according to international guidelines, its
routinary use in patients with cardiogenic shock is not recommended. This recommendation is derived from the results of the IABP-SHOCK II trial, which demonstrated
that IABP does not reduce all-cause mortality in patients with acute myocardial infarction and cardiogenic shock. The present position paper, released by the Italian
Association of Hospital Cardiologists, reviews the available data derived from clinical
studies. It also provides practical recommendations for the optimal use of IABP in
the treatment of cardiogenic shock and advanced acute heart failure.
Left ventricular false tendons (LVFTs) are fibromuscular
structures, connecting the left ventricular
free wall or papillary muscle and the ventricular
septum.
There is some discussion about safety issues during
intense exercise in athletes with LVFTs, as these
bands have been associated with ventricular arrhythmias
and abnormal cardiac remodelling. However,
presence of LVFTs appears to be much more common
than previously noted as imaging techniques
have improved and the association between LVFTs
and abnormal remodelling could very well be explained
by better visibility in a dilated left ventricular
lumen.
Although LVFTsmay result in electrocardiographic abnormalities
and could form a substrate for ventricular
arrhythmias, it should be considered as a normal
anatomic variant. Persons with LVFTs do not appear
to have increased risk for ventricular arrhythmias or
sudden cardiac death.
- Video recording of this lecture in English language: https://youtu.be/kqbnxVAZs-0
- Video recording of this lecture in Arabic language: https://youtu.be/SINlygW1Mpc
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
Does Over-Masturbation Contribute to Chronic Prostatitis.pptxwalterHu5
In some case, your chronic prostatitis may be related to over-masturbation. Generally, natural medicine Diuretic and Anti-inflammatory Pill can help mee get a cure.
Promoting Wellbeing - Applied Social Psychology - Psychology SuperNotesPsychoTech Services
A proprietary approach developed by bringing together the best of learning theories from Psychology, design principles from the world of visualization, and pedagogical methods from over a decade of training experience, that enables you to: Learn better, faster!
These lecture slides, by Dr Sidra Arshad, offer a quick overview of the physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar lead (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
6. Describe the flow of current around the heart during the cardiac cycle
7. Discuss the placement and polarity of the leads of electrocardiograph
8. Describe the normal electrocardiograms recorded from the limb leads and explain the physiological basis of the different records that are obtained
9. Define mean electrical vector (axis) of the heart and give the normal range
10. Define the mean QRS vector
11. Describe the axes of leads (hexagonal reference system)
12. Comprehend the vectorial analysis of the normal ECG
13. Determine the mean electrical axis of the ventricular QRS and appreciate the mean axis deviation
14. Explain the concepts of current of injury, J point, and their significance
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. Chapter 3, Cardiology Explained, https://www.ncbi.nlm.nih.gov/books/NBK2214/
7. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Histololgy of Female Reproductive System.pptxAyeshaZaid1
Dive into an in-depth exploration of the histological structure of female reproductive system with this comprehensive lecture. Presented by Dr. Ayesha Irfan, Assistant Professor of Anatomy, this presentation covers the Gross anatomy and functional histology of the female reproductive organs. Ideal for students, educators, and anyone interested in medical science, this lecture provides clear explanations, detailed diagrams, and valuable insights into female reproductive system. Enhance your knowledge and understanding of this essential aspect of human biology.
Cell Therapy Expansion and Challenges in Autoimmune DiseaseHealth Advances
There is increasing confidence that cell therapies will soon play a role in the treatment of autoimmune disorders, but the extent of this impact remains to be seen. Early readouts on autologous CAR-Ts in lupus are encouraging, but manufacturing and cost limitations are likely to restrict access to highly refractory patients. Allogeneic CAR-Ts have the potential to broaden access to earlier lines of treatment due to their inherent cost benefits, however they will need to demonstrate comparable or improved efficacy to established modalities.
In addition to infrastructure and capacity constraints, CAR-Ts face a very different risk-benefit dynamic in autoimmune compared to oncology, highlighting the need for tolerable therapies with low adverse event risk. CAR-NK and Treg-based therapies are also being developed in certain autoimmune disorders and may demonstrate favorable safety profiles. Several novel non-cell therapies such as bispecific antibodies, nanobodies, and RNAi drugs, may also offer future alternative competitive solutions with variable value propositions.
Widespread adoption of cell therapies will not only require strong efficacy and safety data, but also adapted pricing and access strategies. At oncology-based price points, CAR-Ts are unlikely to achieve broad market access in autoimmune disorders, with eligible patient populations that are potentially orders of magnitude greater than the number of currently addressable cancer patients. Developers have made strides towards reducing cell therapy COGS while improving manufacturing efficiency, but payors will inevitably restrict access until more sustainable pricing is achieved.
Despite these headwinds, industry leaders and investors remain confident that cell therapies are poised to address significant unmet need in patients suffering from autoimmune disorders. However, the extent of this impact on the treatment landscape remains to be seen, as the industry rapidly approaches an inflection point.
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptxHolistified Wellness
We’re talking about Vedic Meditation, a form of meditation that has been around for at least 5,000 years. Back then, the people who lived in the Indus Valley, now known as India and Pakistan, practised meditation as a fundamental part of daily life. This knowledge that has given us yoga and Ayurveda, was known as Veda, hence the name Vedic. And though there are some written records, the practice has been passed down verbally from generation to generation.
Basavarajeeyam is a Sreshta Sangraha grantha (Compiled book ), written by Neelkanta kotturu Basavaraja Virachita. It contains 25 Prakaranas, First 24 Chapters related to Rogas& 25th to Rasadravyas.
2. Al-Zahrani, et al.: TGA – A laterality defect or outflow tract malformation?
238 Annals of Pediatric Cardiology / Volume 11 / Issue 3 / September-December 2018
rather than the congenitally corrected variant, and the
term D‑TGA would indicate the congenitally corrected
variant of TGA rather than the non‑corrected variant. For
reasons of clarity, however, we did not use these terms
as they were used classically. In this study, the formerly
used term “L‑TGA” as a synonym for congenitally
corrected TGA, is now defined only as “levo‑position of
the great arteries” in which the aortic valve is positioned
to the left of the pulmonary valve (such as in the setting
of TGA with additional complicating heart lesions or in
the setting of complex heart defects with an associated
TGA) and will not be used as “L‑TGA” anymore.
TGA is one of the most common and severe malformations
of the heart, accounting for 5% to 7% of all CHD.[3‑6]
It
is the 2nd
most frequent cyanotic CHD, but the most
frequent CHD diagnosed in the neonatal period.[4]
Although it is one of the most common and severe CHDs,
TGA does not have a precedent in phylogeny and
ontogeny, and its etiology and morphogenesis still
remains largely unknown.[6,1,7]
Due to the fact that
TGA is usually associated with parallel (non‑spiraling)
great arteries, such CHDs are suspected to result
from abnormal development of the outflow tract of
the embryonic heart. From the patho‑morphological
standpoint, TGAs do not seem to represent isolated forms
of CHD. They rather seem to represent one end of a
morphological spectrum of CHDs primarily affecting the
ventricular outflows. This spectrum includes ventricular
septal defect with overriding aorta, Tetralogy of Fallot,
double outlet right ventricle with TGA, and TGA. Thus,
in textbooks, TGA is usually considered to be part of
the so‑called “conotruncal heart defect” group, which
is a pathogenetic group of CHD suspected to arise
from abnormal development of the outflow tract of the
embryonic heart.[1,2]
However, recent studies suggest that there is probably
a different etiology involved in the genesis of this
heart defect. It has been speculated that TGA is a
laterality defect in the group of so‑called heterotaxy
syndromes (mirror‑imagery, asplenia/right isomerism
and polysplenia/left isomerism) rather than an outflow
tract defect.[1,8]
Embryonic development of the cardiac outflow tract
The heart originates from progenitor cells within the
mesoderm, the so‑called mesodermal precardiac cells,
and when the heart starts to loop and form, the right – left
axis of the embryo is already mapped.[9,10]
There are three
different groups of these progenitor cells: 1) “first heart
field” cells, which will form the future left ventricle
and the primitive atria including the appendages,[9]
2) “secondary heart field” cells, which are responsible
for the formation of the outflow tract, right ventricle,
atrial myocardium and inflow tract,[11]
3) “extracardiac
cells”, which help in the formation of the coronary
INTRODUCTION
The term “complete transposition of the great
arteries” (TGA) is traditionally used to name congenital
heart defects (CHDs) that are characterized by discordant
ventriculo‑arterial connections. In such a situation, the
morphologically right ventricle is abnormally connected
to the ascending aorta while the morphologically left
ventricle is abnormally connected to the pulmonary trunk.
In the majority of cases, discordant ventriculo‑arterial
connections are associated with parallel (non‑spiraling)
arrangement of the arterial trunks, suggesting that the
condition may have resulted from abnormal development
of the outflow tract of the embryonic heart.[1,2]
Parallel
arrangement (non‑spiraling) of the great arterial trunks,
however, does not necessarily indicate the presence of
TGA. For example, a few cases have been reported in
which TGA occurred with normal spiraling of the arterial
trunks. Furthermore, in cases of CHDs with a solitary
ventricle of indeterminate morphology (“univentricular”
hearts), parallel great arterial trunks cannot be connected
in a discordant fashion to the ventricle since neither a
morphologically right nor a morphologically left ventricle
exists. Parallel arrangement (non‑spiraling) of the great
arterial trunks, thus, should not be named TGA but
rather “malposition of the great arterial trunks”. Four
main types of malposition of the great arteries can be
found in CHDs: (1) “Dextro (D)‑malposition” in which
the aortic valve is to the right of the pulmonary valve;
(2) “Levo (L)‑malposition” in which the aortic valve is to the
left of the pulmonary valve; (3) “Anterior (A)‑malposition”
in which the aortic valve is anterior to the pulmonary
valve, and (4) “Posterior (P)‑malposition” in which the
aortic valve is posterior to the pulmonary valve.
Non‑syndromic cases of complete TGA principally occur in
two variants: (1) in combination with normal (concordant)
atrio‑ventricular connections, or (2) in combination with
abnormal (discordant) atrio‑ventricular connections.
The former variant is frequently called TGA, while
the latter is called congenitally corrected TGA. In
this paper, we will designate “Transposition (TGA)”
as the default term for all CHDs showing discordant
ventriculo‑arterial connections, irrespective of the type
of atrio‑ventricular connections; TGA is used for the
“congenitally non‑corrected” variant of complete TGA,
while congenitally corrected TGA is used to separate
and name the “congenitally corrected” variant. In the
past, the term/abbreviation D‑TGA was frequently
used synonymous for TGA, while levo‑transposition of
the great arteries (L‑TGA) was used as a synonym for
congenitally corrected TGA. Both terms may make sense
only in the setting of usual arrangement of the internal
organs (situs solitus). In the setting of mirror‑imagery of
the internal organs (situs inversus), however, the term
L‑TGA would indicate the non‑corrected variant of TGA
[Downloaded free from http://www.annalspc.com on Saturday, October 20, 2018, IP: 117.197.254.85]
3. Al-Zahrani, et al.: TGA – A laterality defect or outflow tract malformation?
239Annals of Pediatric Cardiology / Volume 11 / Issue 3 / September-December 2018
arteries of the heart and septation of the great vessels:
The extracardiac cells are divided into the so‑called
“cardiac neural crest” cells, which are critical for correct
formation of the great arteries and septation of the
outflow tract. A critical step during heart development is
the so‑called “wedging” process during which the aorta
is positioned behind the pulmonary artery through a
critical counterclockwise rotation of the outflow tract,
so that the aortic valve is settled (wedged) between the
two atrioventricular valves.[11‑15]
Problems during this
critical stage of outflow tract development such as the
failure of migration of the secondary heart field and
cardiac neural crest cells to the outflow tract result in
absence or abnormal spiraling of the aorto‑pulmonary
septum, which in turn can lead to outflow tract defects
such as Tetralogy of Fallot, double outlet right ventricle
and others.[8,9,11,16]
TGA is a linear non spiral development
of the great arteries which is classically regarded as an
outflow tract lesion within this group of outflow tract
defects, too.
Definition and developmental biology of heterotaxy
The right‑left body symmetry is determined in early
embryological phases by various genes. Data from
developmental biology have shown that the development
of the visceral situs is controlled by genes and molecular
left‑right signals, which confer left and right identities
to the lateral plate mesoderms, during the third week
of human embryonic development. Any interruption
in left‑right signaling could result in asymmetrical
development of the internal organs.
In contrary to earlier definitions used by many
clinicians, in our study the term “heterotaxy” is defined
as any departure from the normal arrangement of the
inner organs as proposed recently by Anderson et al.
[Figure 1].[17]
In the setting of usual arrangement of the
internal organs (referred to earlier as “situs solitus”),
the thoraco‑abdominal organs are lateralized, differing
in the anatomical features of their right and left
sides [Figure 1 ‑ left‑hand panel]. The second pattern,
earlier usually described as “situs inversus” represents
lateralized thoraco‑abdominal organs in a mirror‑imaged
variant of the usual bodily arrangement, which is a
clear departure from the normal [Figure 1 ‑ second
left‑hand panel]. Two other settings within heterotaxy
are characterized by visceral symmetry rather than
asymmetry. These bodily arrangements are named
“right isomerism” [Figure 1 ‑ second right‑hand
panel] and “left isomerism” [Figure 1 ‑ first right‑hand
panel]. They are characterized by the presence of
bilateral right‑sidedness or bilateral left‑sidedness
of the inner organs, respectively. Thus, in patients
with right isomerism, both atrial chambers have
a large and pyramid‑shaped (morphologically
right) atrial appendages, both lungs have three
lobes (morphologically right lungs), and the abdominal
situs is frequently characterized by the absence of the
spleen (asplenia). In patients with left isomerism, on
the other hand, both atrial chambers have small and
finger‑shaped (morphologically left) atrial appendages,
both lungs have two lobes (morphologically left lungs),
and the abdominal situs is frequently characterized
by the presence of multiple spleens (polysplenia)
[Figure 1 ‑ first upper row].[17]
Genetics of transposition of the great arteries and
the association with heterotaxy
Interestingly, TGA is very rarely found in genetic
syndromes commonly associated with outflow tract
defects (e. g. Turner, Noonan, or Down’s syndrome).[18]
The
only genetic syndrome demonstrating a strong relation
with TGA seems to be the heterotaxy syndrome.[1,19]
The
parallel (non‑spiral) arrangement of the great arterial
trunks is also present in many patients with a subtype of
double outlet right ventricle (the so‑called double outlet
right ventricle of TGA type, consisting of dextro‑position
of the aorta to the right ventricle and malpositioning of the
pulmonary artery with a subpulmonary interventricular
communication, resulting in TGA physiology), which is
associated with heterotaxy as well, here in particular with
the sub‑group of asplenia/right isomerism. Furthermore,
although TGA with intact ventricular septum is not
associated with heterotaxy, virtually all patients with
heterotaxy and asplenia/right isomerism present parallel
and non‑spiral great arteries in the setting of TGA or
double outlet right ventricle with or without pulmonary
atresia.[19‑29]
A recent screening experiment conducted
on mice showed that some mice mutants with laterality
defects were the same mutants which exhibit CHD,
including TGA. This experiment also demonstrated
that there are mutant genes that caused TGA and
atrioventricular septal defects in all the mice carrying
them. Half of that group of mice showed asplenia/right
isomerism (opposed to polysplenia/left isomerism),
showing the association between TGA, right isomerism
and atrioventricular septal defects.[30‑32]
Therefore,
TGA might have the same etiological background with
heterotaxy, as it has been speculated in previous studies
based on common genes between the two, however the
classical pathogenesis explanation of TGA and heterotaxy
remains unclear.
The primary aim of our study is to clarify whether there is
indeed any association between TGA and morphological
lateralization defects (heterotaxy).
MATERIALS AND METHODS
Study area/setting
The study was conducted in King Abdulaziz Cardiac
Center (KACC), a specialized cardiovascular center in
[Downloaded free from http://www.annalspc.com on Saturday, October 20, 2018, IP: 117.197.254.85]
4. Al-Zahrani, et al.: TGA – A laterality defect or outflow tract malformation?
240 Annals of Pediatric Cardiology / Volume 11 / Issue 3 / September-December 2018
Riyadh, Saudi Arabia. This center has 4 Catheterization
Laboratories, 4 Operating Rooms, and a total of 101 beds,
45 of these beds are Intensive care including a Medical
Cardiac ICU, Cardiac Surgical ICU, Pediatric Cardiac ICU
and a Coronary Care Unit.
Study objects
The study was conducted on 959 TGA patients seen in
this center after applying the following inclusion and
exclusion criteria on 610 patients [Figure 2]:
Inclusion criteria
• All patients registered in the database of this center
who were diagnosed with TGA from 2016 to 2015.
Exclusion criteria
• Patients who didn’t have echocardiograms that
confirm the intracardiac anatomy and diagnosis
• Patients who were extracted from the database as
TGA diagnosis but had echocardiograms that exclude
TGA as the diagnosis
• Patients who had their primary lesion (TGA) repaired
at other institutions, and were then transferred to
this center.
Study design
This is a retrospective cross sectional study, which
had the main goal of identifying the presence of any
association between TGA and heterotaxy (laterality
defects). All patients with TGA within the study period
were analyzed through detailed chart review [Figure 2]
to find out:
1) How many of the identified TGA patients also had a
confirmed heterotaxy (laterality defects)?
2) How many of the TGA patients with heterotaxy
belonged to the group of right isomerism?
3) How many patients with TGA and atrioventricular
septal defects had right isomerism?
4) How many TGA and dextrocardia patients had usual
arrangement of the internal organs (situs solitus)?
Data collection methods, instrument used,
measurements
We conducted this research through chart review of
all patients who presented with a TGA diagnosis to
this center by reviewing in detail their suitability for
the aim of our research. The main variables we looked
at were:
Figure 1: An illustration showing the 4 different variations of bodily organs in the lateralized (left‑hand two columns) and isomeric
(right‑hand two columns) arrangements, including atrial appendages. The upper panels show the atrial appendages morphology, the
second upper panel the bronchial morphology, and the relations of the bronchuses to the pulmonary artery feeding the lower lobes
of the lungs, the third upper panel shows the pulmonary morphology, and the last lower panel shows the arrangement of the liver,
stomach, and spleen. Adopted from: Anderson et al. (J Cardiovasc Dev Dis. 2018;5:11)
[Downloaded free from http://www.annalspc.com on Saturday, October 20, 2018, IP: 117.197.254.85]
5. Al-Zahrani, et al.: TGA – A laterality defect or outflow tract malformation?
241Annals of Pediatric Cardiology / Volume 11 / Issue 3 / September-December 2018
1. A r r a n g e m e n t o f t h e a b d o m i n a l o r g a n s
(usual arrangement (situs solitus), heterotaxy,
including mirror‑imagery (situs inversus), right and
left isomerism) [Figure 1]
2. Cardiac position (levocardia, mesocardia,
dextrocardia)
3. Type of TGA (TGA (discordant ventriculo‑arterial
connection), “congenitally corrected” TGA (discordant
atrio‑ventricular and ventriculo‑arterial connection),
“levo‑position of the great arteries” (which is not
“L‑TGA” that is used by many as synonym for corrected
TGA) in which the aortic valve is positioned to the left of
the pulmonary valve (such as in the setting of TGA with
additional complicating heart lesions or in the setting
of complex heart defects with an associated TGA)
4. C o m p l e x i t y ( S i m p l e T G A ( w i t h o u t
complicating cardiovascular lesions), TGA with
additional complicating heart lesions, TGA in the
setting of complex heart defects) – the detailed
definitions of which are provided in the results
section
5. Interatrial septum status (intact interatrial septum,
primum atrial septal defect, secundum atrial septal
defect/patent foramen ovale, atrioventricular septal
defect)
6. Interventricular septum status (intact interventricular
septum, ventricular septal defect, atrioventricular
septal defect)
7. Presence or absence of atrioventricular septal defect
8. I s o m e r i s m o f t h e a t r i a l a p p e n d a g e s
(usual arrangement (situs solitus), heterotaxy,
including mirror‑imagery (situs inversus), right and
left isomerism) [Figure 1 ‑ first upper row]
9. Aortic arch (left, right)
10. Inferior vena cava (intact, interrupted)
11. Abdominal ultrasound (done, none) [Figure 4]
12. Genetic testing (done, none).
Other data was collected as well, including demographic
data such as: gender, age at diagnosis and date of
birth. The main outcome variable was to find any valid
association between TGA and the before mentioned
variables. These associations would determine if there is
a link between TGA and heterotaxy regarding the genesis
of this congenital heart defect.
For TGA patients two different patient lists were
generated: one ranging from 2002‑2014 and another
one for the year 2015. For TGA patients from 2002‑2014,
we extracted all the patients who were registered in the
database of this center as TGA patients. The data was
extracted by our clinical pediatric research technician in
the center. The patient list was created using the center’s
form for data collection for 2002‑2014 to build up a date
Figure 2: A flowchart showing our research methodology
Figure 3: An inadequate chest X‑ray of a transposition of the great
arteries patient. The quality is not sufficient enough to identify
properly the bronchial tree anatomy
[Downloaded free from http://www.annalspc.com on Saturday, October 20, 2018, IP: 117.197.254.85]
7. Al-Zahrani, et al.: TGA – A laterality defect or outflow tract malformation?
243Annals of Pediatric Cardiology / Volume 11 / Issue 3 / September-December 2018
In addition, the data was reviewed 1) to verify the
diagnosis and all other variables, 2) to fill the missing
data, and 3) to exclude the patients who did not meet the
inclusion criteria. The final number of included patients
after applying the exclusion criteria and the revision
process was 533 TGA patients.
Statistical analysis
Data were analyzed using the IBM SPSS Statistics for
Windows version 22.0 (IBMCorp, Armonk, NY, USA).
Descriptive statistics are presented as the means
standard deviations for numerical variables and as
frequencies with percentages for categorical variables.
The Chi‑squared test or Fisher exact test was used to
compare differences in categorical variables between
the groups. An independent samples t‑test was used
to compare continuous data. A P value < 0.05 was
considered statistically significant.
Ethical considerations
This research was approved by the ethical research
board within the Institutional Review Board (IRB) at the
center’s medical research center with the IRB research
protocol number SP15/016. There was no need for a
consent form since our data collection method consisted
mainly of a chart review. Patients’ confidentiality was
maintained at all levels as only the PI and co‑investigators
had access to the data and were given permission collect
it. In addition, the data collected was kept in a secure
place, using computerized methods in five specific
password‑protected computers, and by using coded serial
numbers; we insured that the data did not contain any
identification of the patients included in the research.
None of the patients’ file numbers (MRN) were sent with
the data for analysis as well.
RESULTS
Study patients
Our study population consisted of all patients who were
diagnosed at KACC with any type of TGA throughout
the years from 2002 – 2015. The originally extracted
population from the records included 610 patients, 77
of which were excluded after thorough record review
per our exclusion criteria (see Materials and Methods).
Of the remaining 533 patients, 262 (49.2%) were
diagnosed as having “Simple TGA”, 57 (10.7%) were
diagnosed as having “TGA with additional complicating
heart lesions”, and 214 (40.2%) were diagnosed as having
“TGA in the setting of complex heart defects”. The mean
age of diagnosis was 8 months. The male to female ratio
was 2 to 1 (male = 351, female = 182). Of the 533 patients
in the study, 35 (6.6%) underwent genetic analysis,
32 (6.0%) of which had normal results and 3 (0.6%)
had positive results, showing deletion syndromes
(not documented which particular syndrome was found).
2 (0.4%) of the patients with deletion syndrome had TGA
in the setting of complex heart defects, and 1 (0.2%) had
Simple TGA.
Simple transposition of the great arteries
This diagnostic sub‑group included all cases of TGA
without additional complicating cardiovascular lesions,
such as pulmonary stenosis, coarctation of the aorta,
and double outlet right ventricle. Patients who had
TGA with ventricular septal defects that did not affect
their clinical presentation, or led to a different initial
surgical approach (such as pulmonary artery banding)
were included in this sub‑group as well. The main
characteristics of Simple TGA patients are shown in
Table 1.
This diagnostic sub‑group comprised 262 (49.2%)
patients of the whole study population. Of these patients,
5 (1.9%) had dextrocardia and 1 (0.4%) had mesocardia.
The heart defects found in this group were defects in the
interatrial or interventricular septum. Secundum atrial
septal defect or a patent foramen ovale were diagnosed in
253 (96.6%) patients, 145 (55.3%) of which had an intact
interventricular septum. On the other hand, a total of
7 (2.7%) patients had a ventricular septal defect with an
intact interatrial septum, and 2 (0.8%) patients had both
an intact interatrial and interventricular septum. Only
2 (0.8%) patients had an atrioventricular septal defect.
The aortic arch was right‑sided in 12 (4.6%) patients.
Usual arrangement of the abdominal organs was found
in the vast majority of cases consisting of 259 (98.9%)
patients. Mirror‑imagery of the abdominal organs was
found in 3 (1.1%) patients. No patient was diagnosed as
having either left or right isomerism.
Transposition of the great arteries with additional
complicating heart lesions
This diagnostic sub‑group included all cases of TGA
with additional complicating heart lesions, such as
multiple ventricular septal defects, pulmonary stenosis,
straddling tricuspid valve, coarctation of the aorta. The
main characteristics of TGA with additional complicating
heart lesions patients are shown in Table 1.
This diagnostic sub‑group comprised 57 (10.7%) patients
of the whole study population. Of these patients, 2 (3.5%)
had dextrocardia and 1 (1.8%) had mesocardia. TGA
was found in 55 (94.5%) patients, while congenitally
corrected TGA was not found in this sub‑group, and
levo‑position of the great arteries was found in 2 (3.5%)
patients.
The complicating cardiovascular defects found in this
group were: 35 (61.4%) pulmonary or sub‑pulmonary
stenosis; 13 (22.8%) coarctation of the aorta; 5 (8.8%)
multiple “Swiss cheese” ventricular septal defects; 3 (5.3%)
[Downloaded free from http://www.annalspc.com on Saturday, October 20, 2018, IP: 117.197.254.85]
8. Al-Zahrani, et al.: TGA – A laterality defect or outflow tract malformation?
244 Annals of Pediatric Cardiology / Volume 11 / Issue 3 / September-December 2018
pulmonary hypertension; 1 (1.8%) atrioventricular septal
defect; 3 (5.3%) straddling tricuspid valve; 1 (1.8%)
interrupted aortic arch. The aortic arch position was
found to be right sided in 7 (12.3%) patients.
Usual arrangement of the abdominal organs was found
in the vast majority of cases consisting of 54 (94.7%)
patients. However, 2 (3.5%) patients were diagnosed to
have mirror‑imagery of the abdominal organs, 1 (1.8%)
patient was found to have right isomerism while no
patient was diagnosed with left isomerism.
Transposition of the great arteries in the setting of
complex heart defects
This diagnostic sub‑group included all cases of TGA
found in the setting of complex cardiac anomalies
(e.g., common atrium, Taussig Bing anomaly, double
outlet right ventricle, etc.). In this group, TGA was not
the clinically leading defect but rather an additional
defect. The main characteristics of TGA in the setting
of complex heart defects patients are shown in Table 1.
This diagnostic sub‑group comprised 214 (40.2%)
patients of the whole study population. Of these
cases, 24 (11.2%) had dextrocardia and 9 (4.2%) had
mesocardia. TGA was found in 127 (59.3%), congenitally
corrected TGA was found in 53 (24.8%) patients,
and levo‑position of the great arteries was found in
34 (15.9%) patients.
The heart defects found in this group were: 72 (33.6%)
double outlet right ventricle; 45 (21.0%) double inlet left
ventricle; 38 (17.8%) Taussig Bing anomaly; 27 (12.6%)
atrioventricular septal defects; 22 (10.3%) pulmonary
atresia; 19 (8.9%) tricuspid atresia; 10 (4.7%) common
atrium; and 4 (1.9%) mitral atresia. The aortic arch was
right sided in 31 (14.5%) patients.
Usual arrangement of the abdominal organs was found
in the majority of cases consisting of 182 (85.0%)
patients, while 16 (7.5%) cases had mirror‑imagery of the
abdominal organs, 7 (3.3%) patients were found to have
left isomerism while 9 (4.2%) patients were diagnosed
with right isomerism.
Transposition of the great arteries and anomalies in
sidedness (lateralization) of the inner organs
Among the whole study population of 533 TGA patients,
495 (92.9%) showed the usual arrangement of the
abdominal organs, out of this group 418 (84.4%) had
TGA, 49 (9.9%) had congenitally corrected TGA, and
28 (5.7%) had levo‑position of the great arteries.
38 (7.1%) patients had heterotaxy, out of this
group 26 (68.4%) had TGA, 4 (10.5%) had congenitally
corrected TGA, and 8 (21.1%) had levo‑position
of the great arteries [for more detailed results see
Tables 2 and 3].
Sub‑groups of heterotaxy in all types of transposition of
the great arteries
Of the 38 patients who had heterotaxy, 21
(3.9% of all cases of TGA) patients were found to have
mirror‑imagery, 7 (1.3% of all cases of TGA) patients
had left and 10 (1.9% of all cases of TGA) patients
had right isomerism. This difference in the incidence
Table 1: Transposition of the great arteries basic divisions according to complexity, and associated
findings in each diagnostic sub‑group
TGA sub‑
grouping
Total Type of TGA Cardiac apical
position
Abdominal
position
Atrial position ASD/PFO VSD AVSD Aortic
Arch
Simple TGA 262 TGA (262) Levocardia (256)
Mesocardia (1)
Dextrocardia (5)
Usual
arrangement (259)
Mirror‑imagery (3)
Usual
arrangement (260)
Mirror‑imagery (2)
253 115 0 Left (250)
Right (12)
TGA with
additional
complicating
heart lesions
57 TGA (55)
Levo‑position of the
great arteries (2)
Levocardia (54)
Mesocardia (1)
Dextrocardia (2)
Usual
arrangement (54)
Mirror‑imagery (2)
Right
isomerism (1)
Usual
arrangement (54)
Mirror‑imagery (2)
Left‑isomerism (1)
50 50 1 Left (50)
Right (7)
TGA in the
setting of
complex
heart defects
214 TGA (127)
Levo‑position of the
great arteries (34)
Congenitally
corrected TGA (53)
Levocardia (181)
Mesocardia (9)
Dextrocardia (24)
Usual
arrangement (182)
Mirror‑imagery (16)
Left isomerism (7)
Right
isomerism (9)
Usual
arrangement (184)
Mirror‑imagery (12)
Left isomerism (8)
Right
isomerism (10)
183 186 27 Left (183)
Right (31)
TGA: Transposition of the great arteries, ASD: Atrial septal defect, PFO: Patent foramen ovale, VSD: Ventricular septal defect, AVSD: Atrioventricular
septal defect
Table 2: Distribution of abdominal visceral
arrangement in relation to the cardiac apex
position in all types of transposition of the great
arteries patients
Abdominal
visceral
arrangement
Cardiac apex position
Levocardia Mesocardia Dextrocardia Total
Usual
arrangement
476 6 13 495
Mirror‑imagery 7 4 10 21
Left isomerism 3 0 4 7
Right isomerism 5 1 4 10
Total 491 11 31 533
[Downloaded free from http://www.annalspc.com on Saturday, October 20, 2018, IP: 117.197.254.85]
9. Al-Zahrani, et al.: TGA – A laterality defect or outflow tract malformation?
245Annals of Pediatric Cardiology / Volume 11 / Issue 3 / September-December 2018
of patients with left isomerism versus right isomerism
in patients with all types of TGA was not statistically
significant (P value of 0.452) [Table 3].
Types of transposition of the great arteries in relation
to abdominal sidedness
444 (83.3%) of all TGA patients had non‑corrected TGA.
Of these patients, 418 (94.1%) had the usual arrangement
of the abdominal organs, 26 (5.9%) patients had
heterotaxy, consisting of 16 (3.6%) with mirror‑imagery
of the abdominal organs, 4 (0.9%) patients were found
to have left isomerism while 6 (1.4%) patients were
diagnosed with right isomerism. 53 (9.9%) of all TGA
patients had congenitally corrected TGA, 49 (92.4%)
of which had the usual arrangement of the abdominal
organs, 4 (7.5%) patients had heterotaxy, consisting of
3 (5.7%) with mirror‑imagery of the abdominal organs,
1 (1.9%) patient was found to have left isomerism while
none were diagnosed with right isomerism. 36 (6.8%) of
all TGA patients had levo‑position of the great arteries,
28 (77.7%) of which had the usual arrangement of the
abdominal organs, 8 (22.2%) patients had heterotaxy,
consisting of 2 (5.6%) with mirror‑imagery of the
abdominal organs, 2 (5.6%) patients were found to
have left isomerism while 4 (11.1%) patients were
diagnosed with right isomerism. However, compared
to TGA and congenitally corrected TGA, levo‑position
of the great arteries showed a stronger association with
heterotaxy (26 (5.9%) patients, 4 (7.5%) patients, and
8 (22.2%) patients, respectively) with a statistically
significant difference (P value of 0.001) [Table 3].
Atrioventricular septal defects in relation to abdominal
sidedness
Atrioventricular septal defects were found in 28 (5.3%)
patients with TGA, out of which 22 (78.6%) had
heterotaxy, consisting of 8 (28.6%) with mirror‑imagery
of the abdominal organs, 5 (17.9%) patients were found
to have left isomerism while 9 (32.1%) patients were
diagnosed with right isomerism [Figure 5].
Arch sidedness in relation to all types of transposition
of the great arteries
In TGA, the incidence of left aortic arch was 408 (91.9%)
versus right aortic arch, which was 36 (8.1%); in
congenitally corrected TGA, the incidence of left aortic
arch was 48 (90.6%) versus right aortic arch, which was
5 (9.4%); and in levo‑position of the great arteries, the
incidence of left aortic arch was 27 (75.0%) versus right
aortic arch, which was 9 (25.0%) [Table 3].
Heterotaxy in arch sidedness in relation to all types of
transposition of the great arteries
In the left aortic arch group (a total of 483 (90.6%)
patients), 13 (2.7%) patients had heterotaxy, 10 (76.9%)
of which were diagnosed with TGA, 1 (7.8%) was
diagnosed with congenitally corrected TGA, and
2 (15.4%) were diagnosed with levo‑position of the great
arteries, while in the right aortic arch group (a total of
50 (9.4%) patients), 25 (50.0%) patients had heterotaxy,
16 (64.0%) of which were diagnosed with TGA, 3 (12.0%)
were diagnosed with congenitally corrected TGA, and
6 (24.0%) were diagnosed with levo‑position of the great
arteries [Table 4].
DISCUSSION
Although many efforts have been made in the past to
uncover the etiology and pathogenesis of TGA, this kind of
congenital heart defect remains a “mysterious” lesion. TGA
is traditionally assigned to the patho‑morphological group
of “conotruncal heart defects”, which includes other lesions
with abnormal positioning of the great arteries, such as
Tetralogy of Fallot and double outlet right ventricle. These
so‑called conotruncal heart defects are suspected to result
from developmental defects of the outflow tract of the
embryonic heart, which are etiologically linked to genetic
defects affecting the development of the secondary heart
field or the cardiac neural crest. Surprisingly, however,
TGA is rarely found in genetic syndromes commonly
linked with outflow tract defects (e.g., Turner, Noonan, or
Down’s syndrome).[18]
Based on a review of various genetic
studies, including their own projects, Unolt et al.[1]
reported
that the only genetic syndrome with a strong association
to TGA is the heterotaxy syndrome, which is etiologically
linked to genetic defects affecting the establishment of the
left‑right body axis.
Table 3: Distribution of anomalies in
sidedness (lateralization) of the inner organs
and aortic arch in relation to different types of
transposition of the great arteries patients
TGA (%) Congenitally
corrected
TGA (%)
Levo‑position
of the great
arteries (%)
Usual arrangement of
the abdominal organs
418 (94.1) 49 (92.4) 28 (77.7)
Mirror‑imagery of the
abdominal organs
16 (3.6) 3 (5.7) 2 (5.6)
Left isomerism 4 (0.9) 1 (1.9) 2 (5.6)
Right isomerism 6 (1.4) 0 4 (11.1)
Left aortic arch 408 (91.9) 48 (90.6) 27 (75.0)
Right aortic arch 36 (8.1) 5 (9.4) 9 (25.0)
Total 444 (100) 53 (100) 36 (100)
TGA: Transposition of the great arteries
Table 4: The distribution of heterotaxy in left aortic
arch in comparison to right aortic arch in all types
of transposition of the great arteries patients
Heterotaxy with
Left aortic
arch (%)
Right aortic
arch (%)
TGA 10 (76.9) 16 (64.0)
Congenitally corrected TGA 1 (7.7) 3 (12.0)
Levo‑position of the great arteries 2 (15.4) 6 (24.0)
Total 13 (100) 25 (100)
TGA: Transposition of the great arteries
[Downloaded free from http://www.annalspc.com on Saturday, October 20, 2018, IP: 117.197.254.85]
10. Al-Zahrani, et al.: TGA – A laterality defect or outflow tract malformation?
246 Annals of Pediatric Cardiology / Volume 11 / Issue 3 / September-December 2018
Our present study aims to clarify whether there is any
statistically significant association between TGA and
clinically diagnosed heterotaxy that may have escaped
the attention of previous investigators. In our study
population of TGA patients, the vast majority of cases
was found to have the usual arrangement of the inner
organs 92.9%, while only 7.1% patients had heterotaxy,
consisting of 3.9% patients with mirror‑imagery, 1.3%
patients with left isomerism and 1.9% patients with right
isomerism. Thus, our present data do not demonstrate
any significant association between TGA and clinically
diagnosed lateralization defects.
We should note, however, that Unolt et al.[1]
have
reported that, in a familial type of heterotaxy syndrome
linked to a ZIC3 gene mutation, congenitally corrected
TGA can occur in association with the usual arrangement
of the inner organs (situs solitus), so that such cases of
congenitally corrected TGA may be regarded as isolated
phenotypic manifestations of heritable heterotaxy
syndromes. In our present study, congenitally corrected
TGA was found in 49 (9.9%) patients with the usual
arrangement of the inner organs. If we would consider
that all these congenitally corrected TGA patients had
a ZIC3 gene mutation, the portion of our patients with
heterotaxy would rise from 7.1% to 16.3% (see Results,
section “TGA and Anomalies in Sidedness (Lateralization)
of the Inner Organs”), which is a value that still does not
indicate any significant association between TGA and
lateralization defects. Moreover, all TGA patients who
had heterotaxy (accounting only for 38 (7.1%) patients)
were linked with other major cardiac anomalies; 32 were
in the sub‑group of TGA in the setting of complex heart
defects, only 3 in the sub‑group of TGA with additional
complicating heart lesions, and only 3 (all of which were
mirror‑imagery) of them was in the sub‑group of the
Simple TGA [Table 1].
There is another striking observation in the literature with
regard to TGA and isomeric hearts. Aune et al.[30]
reported
that half of the mutants with TGA and atrioventricular
septal defect have right isomerism. A similar speculation
was raised by Unolt et al.[1]
by stating that TGA associated
with atrioventricular septal defect has been reported
in almost 100% of cases of asplenia syndrome, which
is a synonym for right isomerism. On the other hand,
Ying‑Liu Yan et al.[33]
reported in their study that out of 18
fetuses with right isomerism, 6 fetuses had TGA and 10
fetuses had atrioventricular septal defects; while only 4
fetuses had both TGA and atrioventricular septal defect.
Further, along with the results of Ying‑Liu Yan et al.,[33]
in our study, we found that out of a total of 533 TGA
patients only 28 (5.3%) patients had atrioventricular
septal defect and only 9 (32.1%) of them were found
to have right isomerism; which shows no significant
association between TGA patients with atrioventricular
septal defect and heterotaxy [Figure 5].
Marinoet al.[21]
reportedintheirstudyonTGAinaspleniaand
polysplenia phenotypes with a total number of 36 patients
with situs ambiguous (that is heterotaxy excluding
mirror‑imagery) a significantly higher incidence of TGA
in patients with right isomerism (20/25 patients (80%))
compared to the incidence of TGA in patients with
left isomerism (2/11 patients (18%)). Although in
our study there was some difference in the incidence
of patients with left isomerism (7 (1.3%)) versus
right isomerism (10 (1.9%)) in all types of TGA, this
was statistically not significant (P value of 0.452) to
indicate that there is any association with either type
of heterotaxy and TGA. However, as shown clearly in
the results section, when we looked into the incidence
of heterotaxy in the different types of TGA, we found
interestingly that compared to TGA and congenitally
corrected TGA, levo‑position of the great arteries showed
a stronger association with heterotaxy (26 (5.9%)
patients, 4 (7.5%) patients, and 8 (22.2%) patients
respectively) with a statistically significant difference
(P value of 0.001) [Table 3].
In right aortic arch, 25 (50.0%) out of 50 patients
had heterotaxy, compared to only 13 (2.7%) out of
483 patients who had left aortic arch. This means
that in our TGA patients with abnormal (right‑sided)
lateralization of the aortic arch, the incidence of
heterotaxy was 19 times higher compared to patients
with the usual (left‑sided) lateralization of the aortic
arch. However, in right aortic arch, 24.0% of the patients
had levo‑position of the great arteries, but in left aortic
arch there were as much as 15.4% of patients who had
levo‑position of the great arteries, making the presence of
levo-position of the great arteries in right aortic arch only
1.6 times higher compared to levo‑position of the great
arteries in left aortic arch. With the previously mentioned
association between heterotaxy and levo‑position of the
great arteries in comparison to TGA and congenitally
corrected TGA with its significant P value of 0.001, the
difference in incidence of levo‑position of the great
arteries in right aortic arch compared to the incidence
of levo‑position of the great arteries in left aortic arch
was expected to be much higher, 4‑10 times as high at
Figure 5: A bar chart showing the distribution of abdominal organ
arrangements in transposition of the great arteries patients who
had atrioventricular septal defect
[Downloaded free from http://www.annalspc.com on Saturday, October 20, 2018, IP: 117.197.254.85]
11. Al-Zahrani, et al.: TGA – A laterality defect or outflow tract malformation?
247Annals of Pediatric Cardiology / Volume 11 / Issue 3 / September-December 2018
least, in support of the association between levo‑position
of the great arteries and heterotaxy [Table 3].
Given the fact that the higher association of levo‑position
of the great arteries and heterotaxy is seen only in
patients in which the primary heart lesion is not TGA
(but a complex heart defect with abnormal positioning of
the great arteries in any form as an additional finding),
to establish a true link is impossible. Therefore, even
the association between levo‑position of the great
arteries and heterotaxy is under question for cofactors
resulting in this link, namely the other major cardiac
anomalies. This can be clearly seen when looking at all
the heterotaxy patients in our population, which is a total
of 38 patients (including patients with mirror‑imagery
as departure from normal), 32 (84.2%) of which were
patients in the sub‑group of TGA in the setting of complex
heart defects, only 3 (7.9%) of which were patients in
the sub‑group of TGA with additional complicating
cardiovascular lesions, and 3 (7.9%) of which were
patients in the Simple TGA sub‑group, showing that
the possible association between heterotaxy and other
major cardiac lesions is more likely than the association
between heterotaxy and TGA [Figure 6 and Table 1].
Limitations
This study used a chart review system as the main basis
for finding all the required variables. Chart review,
however, is inherently limited in data collection,
especially with old data before the era of digital records.
Having said that, all patients with insufficient data were
excluded, namely 10 patients with no echocardiograms
to review, which shows that the significance of the
sample size of the patient population is not affected.
Some variables, including genetic testing, and abdominal
imaging (x‑ray/ultrasound), were not adequately present
in patients’ records. This led to the inability of showing
any association between TGA and specific genetic
abnormalities mentioned in previous papers. On the
other hand, abdominal imaging did not have a major
impact on defining the type of isomerism in our patient
population.
Another limitation was the known variability in defining
the atrial appendages morphology by echocardiograms,
which led to the use of the abdominal visceral situs
acquired by echocardiograms and the bronchial tree in
chest x‑rays to define the type of isomerism.
A more reliable method to classify the type of atrial
appendages’ isomerism is the chest x‑ray showing the
bronchial morphology, because the arrangement of
the atrial appendages is usually congruent with the
bronchial morphology, although this is not always the
case.[17,34]
Even though the arrangement of the abdominal
organs acquired by echocardiograms is not the most
reliable method in defining heterotaxy, the abdominal
Figure 6: A bar chart showing the distribution of abdominal organ arrangements in the transposition of the great arteries sub‑groups
according to complexity
[Downloaded free from http://www.annalspc.com on Saturday, October 20, 2018, IP: 117.197.254.85]
12. Al-Zahrani, et al.: TGA – A laterality defect or outflow tract malformation?
248 Annals of Pediatric Cardiology / Volume 11 / Issue 3 / September-December 2018
echocardiograms were the only choice we could use in
our study since in pediatric patients the actual effective
radiation dose is small resulting in lower quality of
chest x‑rays in relation to identifying the bronchial tree
anatomy.[34,35]
Future studies are needed to uncover the exact etiology and
pathogenesis of TGA by overcoming existing limitations
as mentioned before. A better look into bronchial tree
in chest x‑rays to define the atrial appendages anatomy
and lateralization, and with that the type of isomerism
could lead to a more specific and comprehensive analysis
of TGA patients. A well‑developed protocol in working
up patients with laterality problems, including proper
chest x‑rays, abdominal ultrasounds, comprehensive
echocardiograms, cilia studies, if possible, and genetic
testing as well could ease the collection of robust data
for better conclusive prospective studies.
CONCLUSION
Although genetic data suggest that TGA is etiologically
linked to laterality defects (heterotaxy syndrome),
our present morphological data do not disclose any
significant association between TGA and laterality
defects. With that, our data do not seem to support the
hypothesis of a laterality defect‑based etiology of TGA.
Acknowledgments
We thank Ms Audrey MacDonald, a clinical paediatric
research technician at KACC for her valuable help
during data extraction from our large database and
Ms Natalia C. Caimbon, a cardiac & congenital cardiac
sonographer at KACC for her support during data
collection of the year 2015 that was not included yet in
the database. Finally we would like to express our great
gratitude to Professor Jörg Männer, head of the research
group “Cardio‑Embryology” at the Institute for Anatomy
and Embryology, Georg‑August‑University of Göttingen,
Germany, for his invaluable help and constructive critic
during writing and revision of this manuscript.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
REFERENCES
1. Unolt M, Putotto C, Silvestri LM, Marino D, Scarabotti A,
Valerio Massaccesi, et al. Transposition of great arteries:
New insights into the pathogenesis. Front Pediatr
2013;1:11.
2. Ashworth M, Al Adnani M, Sebire NJ. Neonatal death due
to transposition in association with premature closure
of the oval foramen. Cardiol Young 2006;16:586‑9.
3. Ferencz C, Rubin JD, Loffredo CA, Magee C. The
Epidemiology of Congenital Heart Disease the
Baltimore‑Washington Infant Study (1981‑1989).
Perspectives in Pediatric Cardiology. Vol. 4. Mount
Kisco NY.: Futura Publishing Co., Inc.; 1993.
4. Fyler DC, Buckley LP, Hellenbrand WE, Cohn HE. Report
of the New England regional infant cardiac care program.
Pediatrics 1980;65:375‑461.
5. Samánek M. Congenital heart malformations: prevalence,
severity, survival, and quality of life. Cardiology In The
Young 2000;10:179‑85.
6. Ferencz C, Brenner JI, Loffredo C, Kappetein AP,
Wilson PD. Transposition of great arteries: Etiologic
distinctions of out flow tract defect sinacase‑ control
study of risk factors. In: Clark EB, Markwald RR, Takao A,
editors. Developmental Mechanism of Heart Disease.
Armonk, New York: Futura Publishing; 1995. p. 639‑53.
7. Burggren WW. Cardiac design in lower vertebrates:
What can phylogeny reveal about ontogeny? Experientia
1988;44:919‑30.
8. Ramsdell AF. Left‑right asymmetry and congenital
cardiac defects: Getting to the heart of the matter
in vertebrate left‑right axis determination. Dev Biol
2005;288:1‑20.
9. Schleich JM, Abdulla T, Summers R, Houyel L. An
overview of cardiac morphogenesis. Arch Cardiovasc
Dis 2013;106:612‑23.
10. Horsthuis T, Christoffels VM, Anderson RH, Moorman AF.
Can recent insights into cardiac development improve
our understanding of congenitally malformed hearts?
Clin Anat 2009;22:4‑20.
11. Ward C, Stadt H, Hutson M, Kirby ML. Ablation of the
secondary heart field leads to tetralogy of fallot and
pulmonary atresia. Dev Biol 2005;284:72‑83.
12. Yelbuz TM, Waldo KL, Kumiski DH, Stadt HA, Wolfe RR,
Leatherbury L, et al. Shortened outflow tract leads to
altered cardiac looping after neural crest ablation.
Circulation 2002;106:504‑10.
13. Bajolle F, Zaffran S, Kelly RG, Hadchouel J, Bonnet D,
Brown NA, et al. Rotation of the myocardial wall of the
outflow tract is implicated in the normal positioning of
the great arteries. Circ Res 2006;98:421‑8.
14. Goor DA, Edwards JE. The spectrum of transposition
of the great arteries: With specific reference to
developmental anatomy of the conus. Circulation
1973;48:406‑15.
15. Rokitansky KF. Die Defekte der Scheidewande des
Herzens. Vienna: W. Braumuller; 1875.
16. Le Lièvre CS, Le Douarin NM. Mesenchymal derivatives
of the neural crest: Analysis of chimaeric quail and chick
embryos. J Embryol Exp Morphol 1975;34:125‑54.
17. Anderson RH, Spicer DE, Loomba R. Is an appreciation
of isomerism the key to unlocking the mysteries of the
cardiac findings in heterotaxy? J Cardiovasc Dev Dis
2018;5. doi:10.3390/jcdd5010011.
18. Marino B. Patterns of congenital heart disease and
associated cardiac anomalies in children with Down
syndrome. In: Marino B, Pueschel SM, editors. Heart
[Downloaded free from http://www.annalspc.com on Saturday, October 20, 2018, IP: 117.197.254.85]
13. Al-Zahrani, et al.: TGA – A laterality defect or outflow tract malformation?
249Annals of Pediatric Cardiology / Volume 11 / Issue 3 / September-December 2018
Disease in Persons with Down Syndrome. Baltimore, MD:
Paul H Brookes Publishing; 1996. p. 133‑40.
19. Mohapatra B, Casey B, Li H, Ho‑Dawson T, Smith L,
Fernbach SD, et al. Identification and functional
characterization of NODAL rare variants in heterotaxy
and isolated cardiovascular malformations. Hum Mol
Genet 2009;18:861‑71.
20. Anderson RH, Wilkinson JL, Arnold R, Becker AE,
Lubkiewicz K. Morphogenesis of bulboventricular
malformations. II. Observations on malformed hearts.
Br Heart J 1974;36:948‑70.
21. Marino B, Capolino R, Digilio MC, Di Donato R.
Transposition of the great arteries in asplenia and
polysplenia phenotypes. Am J Med Genet 2002;110:292‑4.
22. Casey BK. Genetics of human left‑right axis malformations.
In: Harvey RP, editor. Heart Development. New York:
Academic Press; 1999. p. 479‑89.
23. Nomura M, Li E. Smad2 role in mesoderm formation,
left‑right patterning and craniofacial development.
Nature 1998;393:786‑90.
24. Gebbia M, Ferrero GB, Pilia G, Bassi MT, Aylsworth A,
Penman‑Splitt M, et al. X‑linked situs abnormalities
result from mutations in ZIC3. Nat Genet 1997;17:305‑8.
25. Ware SM, Peng J, Zhu L, Fernbach S, Colicos S, Casey B,
et al. Identification and functional analysis of ZIC3
mutations in heterotaxy and related congenital heart
defects. Am J Hum Genet 2004;74:93‑105.
26. De Luca A, Sarkozy A, Consoli F, Ferese R, Guida V,
Dentici ML, et al. Familial transposition of the great
arteries caused by multiple mutations in laterality genes.
Heart 2010;96:673‑7.
27. Goldmuntz E, Bamford R, Karkera JD, dela Cruz J,
Roessler E, Muenke M, et al. CFC1 mutations in patients
with transposition of the great arteries and double‑outlet
right ventricle. Am J Hum Genet 2002;70:776‑80.
28. Diano L, Campagnolo L, Vecchione L, Cipollone D, Bueno
S, Prosperini G, et al. Hif1α down‑regulation is associated
with transposition of great arteries in mice treated with
a retinoic acid antagonist. BMC Genomics 2010;11:497.
29. D’Alessandro LC, Latney BC, Paluru PC, Goldmuntz E. The
phenotypic spectrum of ZIC3 mutations includes isolated
d‑transposition of the great arteries and double outlet
right ventricle. Am J Med Genet A 2013;161A: 792‑802.
30. Aune CN, Chatterjee B, Zhao XQ, Francis R, Bracero L,
Yu Q, et al. Mouse model of heterotaxy with single
ventricle spectrum of cardiac anomalies. Pediatr Res
2008;63:9‑14.
31. Yu Q, Shen Y, Chatterjee B, Siegfried BH,
Leatherbury L, Rosenthal J, et al. ENU induced
mutations causing congenital cardiovascular anomalies.
Development 2004;131:6211‑23.
32. Shen Y, Leatherbury L, Rosenthal J, Yu Q, Pappas MA,
Wessels A, et al. Cardiovascular phenotyping of fetal
mice by noninvasive high‑frequency ultrasound
facilitates recovery of ENU‑induced mutations causing
congenital cardiac and extracardiac defects. Physiol
Genomics 2005;24:23‑36.
33. Yan YL, Tan KB, Yeo GS. Right atrial isomerism:
Preponderance in Asian fetuses. Using the
stomach‑distance ratio as a possible diagnostic tool
for prediction of right atrial isomerism. Ann Acad Med
Singapore 2008;37:906‑12.
34. Jacobs JP, Anderson RH, Weinberg PM, Walters HL. The
nomenclature, definition and classification of cardiac
structures in the setting of heterotaxy. Cardiol Young
2007;17 Suppl 2:1‑28.
35. Radiation dose in X‑ray and CT Exams. Radiological
Society of North America (RSNA®); 2017. Available
from: https://www.radiologyinfo.org/en/info.
cfm?pg=about‑rsna. [Last accessed on 2018 Jul 27].38.
Berg C, Bender F, Soukup M, Geipel A, Axt‑Fliedner R,
Breuer J, et al. Right aortic arch detected in fetal life.
Ultrasound Obstet Gynecol 2006;28:882‑9.
[Downloaded free from http://www.annalspc.com on Saturday, October 20, 2018, IP: 117.197.254.85]