Cyanotic congenital heart disease occurs when deoxygenated blood crosses from the right to left side of the heart without passing through the lungs, causing bluish skin. The document discusses the most common causes of cyanotic heart disease including tetralogy of Fallot, transposition of the great arteries, tricuspid atresia, truncus arteriosus, and total anomalous pulmonary venous return. It provides details on the pathophysiology, clinical presentation, investigations, and management of these conditions. Complications include cerebral thrombosis, heart failure, and pulmonary hypertension. Prevention involves screening for maternal infections and illnesses during pregnancy.
2. INTRODUCTION
• Cyanotic congenital heart disease occurs when some of the
systemic venous return (deoxygenated blood) crosses from the
right side of the heart to the left and returns to the body without
going through the lungs (right-to-left shunt).
• Cyanosis (sign): bluish-purple hue to the skin.
• It is most easily seen where the skin is thin, such as the lips,
mouth, earlobes and fingernails.
• Occurs when approximately 5 g/dL of reduced hemoglobin is
present in systemic blood
4. RISK FACTORS
• Chromosomal anomalies.
• Maternal infections: Rubella.
• Maternal Illnesses: Pregestational diabetes
• Medications taken during pregnancy: Antidepressants,
opioids.
• Maternal alcohol use & excessive smoking
5. AETILOGY
• The most common causes of cyanotic congenital heart defects include:
5T’s
Tetralogy of Fallot
Transposition of the great arteries
Tricuspid atresia
Truncus arteriosus
Total anomalous pulmonary venous return
OTHERS
Hypoplastic left heart syndrome
Ebstein anomaly of tricuspid valve
Pulmonary atresia with intact ventricular
septum
Double outlet right ventricle
Single ventricle
6. TETRALOGY OF FALLOT
• Most common cyanotic Heart Disease.
• About 10% of all congenital heart disease
• Allows survival beyond infancy in about 75% of cases.
As a result it is the most common cyanotic CHD
encountered beyond the age of 1-yr constituting
almost 75% of all blue patients.
9. TETRALOGY OF FALLOT CONT.
Pathophysiology.
• Pulmonary stenosis causes concentric right ventricular
hypertrophy and an increase in right ventricular pressure.
• When the right ventricular pressure is as high as the left
ventricular or the aortic pressure, a right to left shunt appears
through the VSD (as it is large enough to allow passage)
• Increasing severity of pulmonary stenosis reduces the flow of
blood into the pulmonary artery and increases the right to left
shunt,
10. TRANSPOSITION OF THE GREAT
ARTERIES
• About 5% of congenital heart defects.
• It is the most common cyanotic lesion to present in the newborn
period.
• Ventriculoarterial discordance secondary to abnormalities of
septation of the truncus arteriosus.
• The aorta arises from the right ventricle, anterior and to the right
of the pulmonary artery, which arises from the left ventricle.
12. TRANSPOSITION OF THE GREAT
ARTERIES CONT.
Pathophysiology.
• Deoxygenated blood returns to the right side of the heart and is
pumped back out to the body, while well-oxygenated blood
returning from the lungs enters the left side of the heart and is
pumped back to the lungs.
• There is a need of mixing of the two circulations without mixing
death occurs quickly.
• Mixing can occur at the atrial (patent foramen ovale/ASD),
ventricular [VSD], or great vessel (PDA) level.
13. TRICUSPID ATRESIA
• Congenital absence of the tricuspid valve resulting in
a hypoplastic right ventricle.
• Approximately 2% of all congenital heart defects.
15. TRICUSPID ATRESIA
Pathophysiology
• All systemic venous return must cross the atrial
septum into the left atrium.
• A PDA or VSD is necessary for pulmonary blood flow
and survival.
16. TRUNCUS ARTERIOISUS
• Less than 1% of all cases of congenital heart disease.
• Failure of septation of the truncus during the first 3 to
4 weeks of gestation.
• A single arterial trunk arises from the heart with a
large VSD immediately below the truncal valve.
• The pulmonary arteries arise from the single arterial
trunk either as a single vessel that divides or
individually from the arterial trunk to the lungs.
19. TOTAL ANOMALOUS PULMONARY
VENOUS RETURN
• About 1% of all congenital heart diseases.
• Disruption of the development of normal pulmonary venous
drainage during the third week of gestation.
• Pulmonary veins fail to connect to the left atrium and return
abnormally via the right side of the heart.
• An atrial-level communication is required for systemic cardiac
output and survival
21. TOTAL ANOMALOUS PULMONARY
VENOUS RETURN
Pathophysiology.
• results in the pulmonary venous blood reaching the
right atrium, which also receives the systemic venous
blood. This results in almost complete mixing of the
two venous returns.
• The blood flow to the left atrium is the right to left
shunt through a patient foramen ovale or atrial septal
defect.
22. HYPOPLASTIC LEFT HEART SYNDROME
• A rare condition but is the most common cause of death from
cardiac defects in the first month of life.
• Occurs when there is failure of development of mitral or aortic
valve or aortic arch.
• A small left ventricle that is unable to support normal systemic
circulation is a central finding.
• Left-to-right shunting occurs at the atrial level.
• Persistence of PDA (Right to left shunting) for systemic blood flow.
24. EBSTEIN ANOMALY
• Downward displacement of an abnormal tricuspid valve into the
right ventricle.
• The right atrium is enlarged because of tricuspid valve
regurgitation
26. SINGLE VENTRICLE
• Both atria empty through a
common atrioventricular valve
• Both aorta and pulmonary artery
arise from a single ventricle , or
may arise from rudimentary
chamber
• Pulmonary stenosis is common
27. DOUBLE OUTLET RIGHT VENTRICLE
• Both aorta and pulmonary artery
arise from right ventricle the outlet
from left ventricle is through the
VSD to RV.
28. PULMONARY ATRESIA WITH
INTACT VENTRICULAR SEPTUM
• The pulmonary leaflets are completely
fused with hypoplastic right ventricle
• Blood goes back through the right atrium
to the left atrium through foramen ovale.
• The only source of pulmonary blood flow
is PDA.
• After birth severely cyanotic with
respiratory distress and if untreated die
within the first week of life.
29. CLINICAL PRESENTATION
HISTORY
• Sx: Bluish discolaration of the skin
• Prolonged crying, irritability
• Easy fatigability and excessive sweating during breastfeeding
• Difficulty in breathing on exertion relieved by squatting
EXAMINATION
• Tachypnea
• Finger clubbing
• Single S2 heart sound
• Murmur
31. MANAGEMENT
• For anomalies that depend on PDA such as transposition of great arteries,
pulmonary atresia give PGE 1 infusion 0.01-0.2 mg/kg .
• Blalock taussing shunt for single ventricle, tricuspid atresia,
• Surgical repair of VSD and pulmonary stenosis patching or repair in TOF.
• Arterial switch in the first 2 weeks for transposition of great arteries
• Aortopulmonary shunt with pulmonary valvotomy
32. COMPLICATIONS AND PREVENTION
Complications.
• Cerebral thrombosis
• Brain abscess ,bacterial endocarditis, heart failure, stroke
• Pulmonary hypertension
Prevention
• Screening for torches
• Diabetic mothers should control their blood glucose
• Screening for genetic diseases
