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
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.
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.
Tricuspid atresia is a form of congenital heart disease whereby there is a complete absence of the tricuspid valve. Therefore, there is an absence of right atrioventricular connection. This leads to a hypoplastic (undersized) or absent right ventricle.
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.
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.
Tricuspid atresia is a form of congenital heart disease whereby there is a complete absence of the tricuspid valve. Therefore, there is an absence of right atrioventricular connection. This leads to a hypoplastic (undersized) or absent right ventricle.
a cardiac surgery presentation about Atrioventricular septal defect,Definition, Prevalence,Anatomy,Classification,presentation ,diagnosis and management
This presentation talks about the ventricular septal defect definition, incidence rate, Genetics, morphology, physiology, classification, investigations and management
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
- 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
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
Muktapishti is a traditional Ayurvedic preparation made from Shoditha Mukta (Purified Pearl), is believed to help regulate thyroid function and reduce symptoms of hyperthyroidism due to its cooling and balancing properties. Clinical evidence on its efficacy remains limited, necessitating further research to validate its therapeutic benefits.
2. • Complete transposition of the great arteries (TGA)
is a congenital cardiac defect in which there is
anatomic reversal of the relationship of the great
arteries: The aorta arises entirely or largely from
the right ventricle, and the pulmonary artery arises
entirely or largely from the left ventricle
(ventriculoarterial discordant connection).
A. Ventriculo-arterial discordance
B. Great vessels reversed
C. Aorta anterior and slightly rightward
D. Most common CHD in infancy
3. TGA is a relatively common form of congenital
heart disease, accounting for 9.9% of infants with
congenital heart disease in a New England study
and representing a frequency of 0.206 per 1,000
live births.
There is a male-to-female ratio of 2 to 1, which
increases to 3.3 to 1 when the ventricular septum is
intact. In complex forms of transposition, a sexual
predominance has not been noted
Untreated, 90% of children with D-TGA and an
intact septum will die by 1 year of age
4. Despite its overall low prevalence, transposition
of the great arteries is the most common
etiology for cyanotic congenital heart disease in
the newborn
The inheritance is multifactorial
. Transposition of the great arteries is isolated in
90% of patients and is rarely associated with
syndromes or extracardiac malformations.
This congenital heart defect is more common in
infants of diabetic mothers
5. Transposition of the great arteries (TGA) was first recognized and
described over two centuries ago. Although reference was made to
malposition of the aorta and pulmonary artery (PA) by Steno in 1672
and Morgagni in 1761, the anatomical description of TGA is credited
to Baillie in 1797.
It was Farre in 1814 who introduced the term transposition of aorta
and PA, meaning that the aorta and PA are displaced across the
ventricular septum
An attempt to classify the various types of transposition was reported
by Von Rokitansky, and the first clinical
recognition of TGA in life was noted by Fanconi in 1932. In 1938,
Taussig described the pathological anatomy and hemodynamic and
clinical characteristics of the cardiac defect
. in 1971 Van Praag clarified the definition of TGA to include only
when there is ventriculararterial discordance and other abnormalities
of position as malposition
6. . the surgery for TGA started in 1950 with the Blalock-Hanlon
operation which was an atrial
septectomy which remained popular until the introduction of
the Rashkind balloon atrial septostomy
. the first successful atrial switch was accomplished by Senning in
1958 this was completed by using an intratrial baffle using the
tissue between right atrial wall and atrial septum
the Mustard pericardial atrial baffle operation was introduced in
1963
. in 1975 Jatene reported his initial successful experience with the
arterial switch operation, including coronary transfer, for TGA
with VSD
in 1983 several independent groups began to use the arterial
switch operation for neonates with an intact ventricular septum as
the primary procedure for TGA
7. Several theories have been advanced. It has been suggested that the
subaortic conus persists and develops during normal looping of the
ventricles while the subpulmonary conus undergoes absorption and
thus establishes eventual fibrous continuity between the mitral and
pulmonary valves, the reverse of the normal situation
.In the normal heart the subaortic conus does not grow, and dominant
growth of the pulmonary conus forces the pulmonary valve anterior
superior, and to the left. In transposition, differential growth of the
subaortic conus pushes the aorta anteriorly and disrupts aortic to mitral
valve continuity. If the subpulmonary conus fails to develop, the PA will
maintain a posterior location and pulmonary to mitral valve continuity
will occur. As a consequence of this relationship, the aortic valve becomes
anterior to the pulmonary valve, permitting both semilunar valves to
connect with the distal great vessels without the rotation that is
hypothesized to occur in normal cardiac development
Because conal development determines rotation of the truncus arteriosus,
the great arteries are similar in relationship at the semilunar valves as
they are at the arch, resulting in no twist in the great arteries.
8.
9.
10. The major anatomic classifications of transposition of the great
arteries depend on the relationship of the great arteries to each
other and/or the infundibular morphology.
. In approximately 60% of the patients, the aorta is anterior and to
the right of the pulmonary artery (dextro-transposition of the
great arteries [d-TGA]). However in a subset of patients, the aorta
may be anterior and to the left of the pulmonary artery (levo-
transposition of the great arteries [l-TGA]).
From a practical standpoint, the presence or absence of associated
cardiac anomalies defines the clinical presentation and surgical
management of a patient with transposition of the great arteries
. The primary anatomic subtypes are (1) transposition of the great
arteries with intact ventricular septum, (2) transposition of the
great arteries with ventricular septal defect, (3) transposition of
the great arteries with ventricular septal defect and left ventricular
outflow tract obstruction, and (4) transposition of the great
arteries with ventricular septal defect and pulmonary vascular
obstructive disease.
11. . Normal atrial situs occurs in 95% of patients, a
true ostium secundum atrial septal defect (ASD) is
present in 10% to 20% of cases, the majority of
atrial communications are through a patent
foramen ovale.
. Right aortic arch is present in 4% of patients with
intact ventricular septum and up to 16% of those
with VSD
Up to 50% of patients with TGA have an
associated VSD, many of which
spontaneously close.[52] The VSDs are commonly
perimembranous.
12.
13. The L-loop right ventricle is left-handed. Figuratively speaking, the thumb of the left hand goes through the tricuspid
valve (TV), representing the right ventricle (RV) inflow tract (IN). The fingers of the left hand go into the RV outflow tract
(OUT). The palm of only the left hand faces the RV septal surface. The dorsum of only the left hand is adjacent to the RV
free wall surface. Because L-loop RV is left-handed, some of our colleagues call L-loop ventricles left-hand topology. This
is a case of congenital physiologically corrected TGA {S,L,D} with AV discordance and VA discordance, superoinferior
ventricles, and crisscross AV relations. Some L-loop ventricles appear to be truly inverted, as with mirror-image
dextrocardia in situs inversus totalis {I,L,I}. However, often L-loop ventricles, as with classical congenital physiologically
corrected TGA {S,L,L}, or, as in this case—TGA {S,L,D}—may be only apparently inverted, that is, a solitus heart tube that
has undergone L-looping (an L-malrotated solitus heart tube). L-loop formation has definitely occurred in both of the
previous examples, but only one (i.e., {I,L,I})may be truly inverted. This is why we prefer to talk about D-loop ventricles
and L-loop ventricles (rather than noninverted and inverted ventricles, respectively). Thus when the ventricles are very
malrotated, and consequently diagnostically potentially confusing, chirality is helpful.Abbreviations are the same as
previously.
14. The D-loop right ventricle (RV) is right-handed. Figuratively speaking, the thumb of the right hand goes
through the tricuspid valve (TV), indicating the RV inflow tract (IN). The fingers of the right hand go into the
RV outflow tract (OUT). The palm of only the right hand faces the RV septal surface, and the dorsum of only
the right hand is adjacent to the RV free wall surface. Handedness or chirality is helpful in making the diagnosis
of the ventricular situs (D-loop versus L-loop) when the conventional definition of noninversion or inversion
relative to the sagittal plane breaks down, as in this case of superoinferior ventricles with crisscross
atrioventricular (AV) relations. Both ventricles are bilateral (right-sided and left-sided). Because D-loop RV is
right-handed, some of our colleagues call D-loop ventricles right-hand topology. This is a case of physiologically
uncorrected (“complete”) transposition of the great arteries (TGA) {S,D,L} with AV concordance,
ventriculoarterial (VA) discordance, superoinferior ventricles, and crisscross AV relations. Ao, Aorta; AS, atrial
septum; AVVs, atrioventricular valves; LPA, left pulmonary artery; MPA, main pulmonary artery; MV, mitral
valve; RPA, right pulmonary artery; VS, ventricular septum
15. In approximately one third of patients with
transposition of the great arteries, the coronary artery
anatomy is abnormal
with a left circumflex coronary arising from the right
coronary artery (22%)
A single right coronary artery (9.5%), a single left
coronary artery (3%), or inverted origin of the coronary
arteries (3%) representing the most common variants
Intramural coronary arteries that proceed in the aortic
wall for a distance before exiting to the epicardial
surface have been described and commonly occur at
the commissural attachment of the semilunar valve
16. The six most common types of
coronary artery anatomy in
TGA. Descriptive classification is
on the left, and three simplified
classification codes are described
on the right
17. Yacoub and Radley-Smith (1976) described five basic
coronary artery configurations and methods for their
transfer .
18. A. Separate parallel circulation(The parallel relationship of
the pulmonary and systemic circulations in TGA results in
nonoxygenated venous blood passing through the right
ventricle to the aorta, whereas the oxygenated pulmonary
venous blood passes through the left ventricle back to the
pulmonary arterial circulation)
B. Degree of cyanosis depends on mixing
C. VSD patients less cyanotic
(. Mixing between the pulmonary and systemic circulations at
the atrial, ventricular, or great vessel level through a patent
foramen ovale or atrial septal defect, a VSD, or a patent
ductus arteriosus, respectively, is mandatory for survival.
Patients with TGA and an intact ventricular septum survive
initially because of aortopulmonary flow through a patent
ductus arteriosus)
19. LV thickness/function diminished > 1 month(which the left ventricle ejects to the
low-resistance pulmonary vascular bed. Thus, the left ventricle does not increase
muscle mass relative to the right ventricle and within a few weeks loses the ability
to maintain adequate cardiac output against significant afterload).
This change occurs despite the fact that the left ventricle maintains a volume load
in patients with transposition and intact ventricular septum. However, when a VSD
or large patent ductus arteriosus is present, both volume and pressure overload of
the left ventricle is maintained.
After birth, both ventricles are relatively noncompliant, and infants with
transposition often have an increased pulmonary blood flow, which causes
enlargement of the left atrium and functional incompetence of the foramen ovale,
resulting in atrial level mixing of oxygenated and nonoxygenated blood.
Inadequacy of this mixing, however, may result in only marginal tissue
oxygenation that does not improve with oxygen administration. Atrial balloon
septostomy results in improved admixture and an improved tissue oxygen delivery
in these patients
. These physiologic changes in the neonatal heart are important for the
consideration of surgical approaches because after a few weeks of post uterine life,
the left ventricle in D-transposition with intact ventricular septum takes on the
characteristics and wall thickness of a pulmonary ventricle and may not be
adequate to support the systemic circulation.
20.
21.
22. The mortality rate in untreated patients is approximately 30% in the first
week, 50% in the first month, and 90% by the end of the first year. With
improved diagnostic, medical, and surgical techniques, the overall short-term
and midterm survival rate exceeds 90%.
Long-term complications are secondary to prolonged cyanosis and include
polycythemia and hyperviscosity syndrome. These patients may develop
headache, decreased exercise tolerance, and stroke. Thrombocytopenia is
common in patients with cyanotic congenital heart disease leading to bleeding
complications.
Patients with a large ventricular septal defect, a patent ductus arteriosus, or
both may have an early predilection for congestive heart failure, as pulmonary
vascular resistance falls with increasing age. Heart failure may be mitigated in
those patients with left ventricular outflow tract (pulmonary) stenosis
A small percentage (approximately 5%) of patients with transposition of the
great arteries (and often a ventricular septal defect) develop accelerated
pulmonary vascular obstructive disease and progressive cyanosis despite
surgical repair or palliation. Long-term survival in this subgroup is
particularly poor.
23. Cyanosis: simple >VSD
(arterial partial pressure of oxygen 25 to 40 mm Hg), which varies
in degree depending on associated anomalies. Typically, the
cyanosis is more pronounced when the ventricular septum is
intact and is often present at birth. The development of cyanosis
later in infancy is usually associated with the presence of a
significant VSD or left ventricular outflow tract obstruction.
Congestive heart failure may be the predominant clinical finding
in patients with a large VSD or patent ductus arteriosus.
Symptoms of cardiac failure, however, are rarely present in the
first week of life but commonly appear by 1 month of age as
pulmonary vascular resistance decreases and pulmonary blood
flow becomes excessive, even in a patient with an intact
ventricular septum.
. Earlier presentation: simple > VSD and PS > VSD
. Soft systolic murmur
24. A. CXR
1) Normal at birth
B. Echo
1) Posterior branching great vessel
2) Intracardiac anatomy defined
3) Coronary ostia defined
C. Catheterization
1) Septostomy or coronary anatomy
25. Parasternal short-axis
view of the heart in
D-TGA and intact
ventricular septum
with usual coronary
anatomy. Coronary
arteries are noted to
arise from the left and
right coronary cusps,
and the pulmonary
artery is posterior. AO,
aorta; LCA, left
coronary artery; PA,
pulmonary artery; RCA,
right coronary artery
26. A. diagnosis can be made with 2-D echocardiography
1) ECHO can define the VSD anatomy, mitral valve
morphology and the anatomy of the left ventricular outflow
tract
2) ECHO can delineate the proximal portions of the
coronaries (including intramural)
3) can study the direction of the ventricular septum bowing
in order to ascertain the relative LV and RV pressures
a) if the LV to RV pressure ratio is <0.6 there is an increased
probability for LV failure after an arterial switch operation
4) most neonates can be operated on the basis of the ECHO
findings
5) cardiac catheterization is performed when there is
uncertainty about the presence of a left ventricular outflow
tract obstruction or to study aortic arch anomalies
27. B. patients with an intact ventricular septum or with a
small VSD are offered the arterial switch operation as
primary treatment
C. balloon atrial septostomy can be performed in order to
stabilize the neonate prior to definitive repair
D. when the LV to RV pressure ratio is <0.6, these patients
can undergo pulmonary artery banding and systemic to
pulmonary artery shunt placement in order to condition the
left ventricle prior to the arterial switch procedure
E. in patients with a nonrestrictive VSD, the arterial
switch operation can be performed beyond the neonatal
period
F. fixed LV outflow obstruction or significant pulmonary
valve stenosis are contraindications to the arterial switch
operation
28. This is a rather complicated topic, so I will split
it into sections –
initial stabilization,
palliative treatment and
definitive treatment.
29. A. Correct acid-base abnormalities
B. . PGE-1
C. Increase pulmonary blood flow / mixing
the first treatment measure is to improve mixing of
venous and arterial blood. And the best method is to
start a "prostaglandin drip". This must only be done
in a well equipped hospital, under the guidance of
qualified physicians. Prostaglandin can suppress
breathing, and sometimes the child may need to be
connected to an artificial respirator. Oxygen may
need to be administered by an "oxygen tent" or
mask.
30. . In TGA, palliation is usually achieved by trans-catheter methods.
The wall between the right and left atrium is punctured and the
catheter device pushed through the small hole thus created. The
balloon is then inflated, and the catheter is pulled back through the
small hole, tearing it and making it larger. This procedure is called a
Balloon Atrial Septostomy and was first devised by Dr.Rashkind
The aim is to create a large enough opening between the two atria, so
that blood can freely mix across it, and improve oxygen supply.
Sometimes, a balloon atrial septostomy does not provide adequate
mixing, or cannot be carried out at all. In this situation, surgical
creation of a "hole" in the wall between the atria is necessary
. The operation was first described by Drs.Blalock and Hanlon, and is
called an atrial septectomy. It is a "closed-heart" operation, in which a
part of the atrial septum is surgically removed after applying special
clamps on the heart to prevent bleeding. The results of atrial
septectomy are usually good.
33. Basically, there are two ways to deal with the
abnormality of TGA. First, the venous blood returning
to the right atrium can be diverted to the LEFT ventricle,
from where it will go to the lungs through the
pulmonary artery. At the same time, the pure blood
returning from the lungs will be diverted to the RIGHT
ventricle which will pump it into the aorta. This
operation is performed from within the atrium, and is
called an ATRIAL SWITCH OPERATION
The second approach is easier to understand. The aorta
and pulmonary artery are divided, their positions
"switched" and stitched back to their CORRECT
ventricles - the aorta to the LEFT ventricle and the
pulmonary artery to the RIGHT. This is called the
ARTERIAL SWITCH OPERATION
34. What is the Arterial Switch Operation ?
• This elegant operation is simple in concept. Yet it was
only first successfully performed in the late 1970s by
Dr.Jatene in Brazil
• This was mainly due to the technical difficulty in
connecting the CORONARY ARTERIES to the new
aorta.
How is an arterial switch operation (ASO) done ?
Steps in Arterial Switch Procedure
A. Excision coronary arteries
B. Transfer coronary arteries to neo-aorta
C. LeCompte maneuver
D. Neo-aorta anastomosis
E. Reconstruct neo-pulmonary root - pericardium
35.
36.
37. the advantages of an arterial switch operation?
A. It restores normal structure to the heart. After the
operation, the anatomy of the heart is just as in normal
people. The heart is almost as good as new.
B. The left ventricle is what pumps blood to the rest of the
body. In the atrial switch operation, it is the right
ventricle that does this job. the right ventricle is
designed for less severe work - pumping blood to the
lungs alone. When it is made responsible for the blood
flow to the rest of the body, it may not be able to cope
with the increased demands. Over many years, it may
"fail". With the left ventricle, there is no such problem.
C. Since there is very little suturing to be done inside the
heart itself, the chances of later scarring causing
rhythm disturbances - arrhythmias - are less with
arterial switch operation.
38. What are the problems with an ARTERIAL
switch operation (ASO) ?
A. ASO is a technically demanding and difficult
operation, and may take sometime to perfect.
B. Different surgeons and institutions have varying
results.
C. ASO is not suited for all patients
D. . Abnormalities in coronary arteries greatly
increase the difficulty of an ASO
E. And an ASO cannot be performed in patients who
come to medical attention at an older age, or who
have severe pulmonary valve abnormalities.
39. Results of Arterial Switch
A. Operative mortality = 2-5%
B. Higher mortality - single
coronary/intramural coronary
C. Supravalvular PS = 10-15%
D. Sinus rhythm > 95%
E. 90% survival at 5 years
40.
41. There are two types of atrial switch operations -
the MUSTARD operation, and the SENNING
operation. Both are similar in principle, but differ
in technique.
. The right atrium is opened, and the wall between
the atria is fully removed. Using pericardium
(Mustard) or flaps created from the atrial septum
and wall (Senning), a "baffle" is constructed
directing blood from the veins in the right atrium
towards the left ventricle. The same baffle also
directs blood from pulmonary veins to the right
ventricle. The circulation is therefore restored to
normal in a functional sense.
42.
43.
44.
45.
46. When should an atrial switch operation be preferred ?
The atrial switch was the first to be developed for TGA and was
frequently performed in the 1970's and early 80's.
It has many drawbacks, and so today, the ARTERIAL switch is
the operation of choice for TGA. Still, Mustard and Senning
operations are not obsolete.
Some patients are not suited for an arterial switch procedure.
This may be due to severe abnormalities of their coronary
arteries, which make it very difficult for the surgeon to re-
implant them at operation.
If the patient comes to medical attention at a later age - beyond
1 to 2 months - an arterial switch is not possible
Some institutions may not have adequate experience with
arterial switch, which is a difficult operation to learn. In any of
these situations, an atrial switch procedure - Mustard or
Senning - may be preferred
47. What are the problems with an ATRIAL
switch procedure ?
(Disadvantages of Atrial Switch)
A. SVC obstruction - Mustard > Senning
B. Supraventricular arrhythmias
C. Baffle leaks
D. Tricuspid insufficiency
E. Late RV failure
F. Exercise capacity is less than normal.
48. TGA after 2 months of age - the Rapid Two-Stage ASO
When a child with TGA comes for treatment only after 4 to 8
weeks, the left ventricle is too weak to support the
circulation after an ASO. To prepare the left ventricle, an
initial operation called "banding" is done. A tape or thread is
placed around the artery arising from the left ventricle (i.e.
pulmonary artery in TGA) to constrict it and make it
narrow. The left ventricle is thus "trained" to work against
the higher resistance produced by this narrow outflow and
becomes stronger and thick walled. Within two weeks, an
ASO is then performed with a better outcome, since the left
ventricle is now capable of handling its workload of
pumping blood to the entire body. This is called the rapid
two-stage ASO and was devised by Dr.Aldo Castaneda.
49. A. Repair birth to 2 months
B. Standard arterial switch
C. Trans-atrial closure VSD
D. Mortality rate = 5-10%
50. TGA with a narrow pulmonary valve -
Alternate Operations.
After an ASO, the pulmonary valve is now
shifted to the left ventricle, a region of higher
pressures than the right. If the pulmonary
valve is narrow or abnormal, it cannot function
normally in the high pressure area. So other
procedures have been devised for these
patients.
51. RASTELLI procedure
In this operation, the pulmonary valve is
surgically closed. A tube or conduit in which a
valve is placed, is used to connect the right
ventricle to the pulmonary artery. This avoids
including the abnormal pulmonary valve in the
circulation. One disadvantage with this
operation is that in very small children, a
second operation will be needed to replace the
conduit as the child outgrows it.
53. LECOMPTE (or REV) procedure
The Lecompte procedure (Lecompte et al., 1982), an
alternative to the Rastelli operation, involves extensive
resection of infundibular septum between the aortic
orifice and VSD. Pulmonary artery is then reimplanted
directly on the RV without an extracardiac conduit.
Utilization of the Lecompte manoeuvre depends on the
position of the great arteries (Vouhe et al., 1992).
This is similar to the Rastelli operation, but aims to
avoid the complications related to using a conduit. The
pulmonary artery is moved close to the right ventricle,
and sewn to it DIRECTLY, using a patch of
pericardium to widen the junction.
55. NIKAIDOH procedure
Another alternative was described by Nikaidoh (1984).
It consists of posterior translocation of the aortic root
with biventricular ouflow tract reconstruction. Division
of the outlet septum towards the VSD
The narrowed LVOT is augmented with a prosthetic
patch. The Lecompte procedure can also be added.
This procedure is probably suitable for some patients
who may have suboptimal anatomy for Rastelli
operation.
In this operation, the aorta is "switched" ALONG
WITH THE AORTIC VALVE and placed in the
pulmonary position. This avoids leak of a faulty
pulmonary valve on the left side.
56. Figure 1: Left: the areas of aortic root
harvesting and main pulmonary artery
transection are demarcated.
Right: once the aortic root has been
separated from the right ventricle and the
pulmonary artery transected, the infundibular
septum is divided.
Figure 2: Left: the posterior half of the
aortic annulus is sutured to the
pulmonary valve annulus.
Right: the ventricular septal defect is closed
with a patch, which is also sutured to the
anterior rim of the proximal aortic root.
NIKAIDOH procedure
57. Figure 3: Left: the aorta is transected
and the Lecompte maneuver performed.
Right: once aortic continuity is reestablished,
the anterior aspect of the hypoplastic main
pulmonary artery is open longitudinally.
Figure 4: Left: the posterior aspect of the
main pulmonary artery is sutured to the
right ventricular outflow tract.
Right: right ventricle to pulmonary artery
continuity is completed with an anterior patch
of autologous pericardium, which is also
utilized to augment the main pulmonary
artery.
59. A. Mayo Clinic experience
1) series of 117 patients
2) all patients have D-transposition, VSD, and pulmonary stenosis
3) age range 4 months to 29 years
4) 68% patients had received previous palliative surgery (most had systemic to
pulmonary shunt)
5) overall mortality was 16%
a) influenced by young age <5 years and small size of patient
b) also related to position of VSD with best results with perimembranous VSD’s
c) late deaths are due to sudden death and pulmonary hypertension, left ventricular
dysfunction, mitral insufficiency and bacterial endocarditis
6) ten year survival was 61 %
7) most common cause of for reoperation is obstruction of the extracardiac conduit
a) may fail secondary to calcification or anterior compresion esp. in irradiated
homografts and valved dacron conduits
b) in recent yearts cryopreserved aortic and pulmonary valved homografts have been
conduit of choice
c) probability of conduit replacement is 62% at 10 years and 80% at 15 years
60. Lecompte performed 94 REV procedures between 1985
and 1992. Fourteen patients died (14%). Vouhe et al.
(1992) compared the results of REV and Rastelli operations
in their institution
Twenty-two patients underwent Rastelli procedure, 40
patients underwent the Lecompte operation (REV).
Two patients died after Rastelli (9%) and five after REV
(12.5%). The difference was not statistically significant.
There were eight late reoperations (five in the Rastelli
group, three in REV
both procedures provide satisfactory results. However,
the Lecompte operation is feasible in infancy and it
may reduce the need for reoperation for the outflow
tract obstruction.
61. The overall experience with aortic translocation is
somewhat limited and there are just a few reports
in the medical literature.
Morell et al. (2005) reported 12 patients who
underwent aortic translocation between 1996 and
2005.
One patient died after the operation (8.3%). Three
patients have undergone four reoperations.
Nikaidoh reported excellent results in a series of 17
patients undergoing aortic translocation with one
early death and no late mortality with a mean
follow-up period of 11.4 years. None of the
patients developed significant aortic insufficiency.
62. A. TGA/IVS simple - Arterial switch < 14 days
B. TGA/IVS simple with intramural L main -
Mustard/Senning
C. TGA/VSD - neonatal switch and VSD
closure
D. TGA/VSD/PS - shunt; Rastelli 1-2 years