Presentation on theme: "Pulmonary atresia with intact ventricular septum"— Presentation transcript:
1 Pulmonary atresia with intact ventricular septum
2 Pulmonary atresia and intact ventricular septum was first described in 1784 by Hunter Robert M. Freedom- described the diversity of this malformation and emphasized the complexity of this disorder
3 EpidemiologyNew England Regional Infant Cardiac Program identified 75 patients with this disorder- 3.1% of all infants enrolled in the studyBaltimore-Washington Infant Study defined the prevalence for this disorder as per 1,000 live births
4 Levocardia, normal atrial relations, concordant atrioventricular connections, and concordant ventriculoarterial connectionsRight ventricular outflow tract is imperforate.Either membranous or muscular atresia.The ventricular septum is intact.
6 Pulmonary blood flow is usually mediated by a PDA Multiple direct aortopulmonary collaterals originating from the descending thoracic aorta may be the sole sources of pulmonary arterial supply rarely.Nonconfluent pulmonary arteries, each supplied by a patent arterial duct may also occur rarely.
7 MorphogenesisKutsche and Van Mierop theoryPulmonary atresia with ventricular septal defect occurs earlier in cardiac morphogenesis than pulmonary atresia and intact ventricular septum.Pulmonary atresia and ventricular septal defect occur early in cardiac morphogenesis, after partitioning of the truncoconal part of the heart but before closure of the ventricular septum.
8 Pulmonary atresia and intact ventricular septum occur after cardiac septation. Reflects a prenatal inflammatory disease rather than a true congenital malformationKutsche LM, Van Mierop LH. Pulmonary atresia with and without ventricular septal defect: A different etiology and pathogenesis for the atresia in the 2 types? Am J Cardiol 1983;51:932â
9 Few data to support an inflammatory process Histopathological studies provided no evidence of inflammation.
10 Obligatory right-to-left shunt at atrial level-either a patent foramen ovale or true secundum atrial septal defectIf the interatrial septum is intact -alternative pathways for systemic venous return - coronary sinus to left atrial fenestration.
11 Tricuspid ValveRanges from extreme stenosis to severe regurgitationSeverely regurgitant valve -dilated annulus.The valve may exhibit Ebstein anomaly.Extremely dysplasia also seen.
12 Patients with the largest right ventricles usually have severe tricuspid regurgitation with valves exhibiting features of Ebstein's anomaly and dysplasia.A major management challenge with a poor overall prognosis.
13 Right VentricleCongenital Heart Surgeons Study (CHSS)-the use of the tricuspid diameter Z valueIt is the diameter of the tricuspid valve normalized to body surface area.Data from the CHSS showed that the Z value of the tricuspid valve correlated with the size of the right ventricular cavity (p <0.0001)
14 Relief of outflow tract obstruction with associated pulmonary insufficiency may result in remodeling with regression of hypertrophy that can result in real or perceived growth of the right ventricleDaubeney PE, Delany DJ, Anderson RH, et al. Pulmonary atresia with intact ventricular septum: Range of morphology in a population-based study.J Am Coll Cardiol 2002;39:1670Freedom RM. How can something so small cause so much grief? Some thoughts about the underdeveloped right ventricle in pulmonary atresia and intact ventricular septum.J Am Coll Cardiol 1992;19:1038
15 Well developed RV with hypertrophy-inlet,trabecular and outlet well developed -good prognosis. Small RV cavity (66%)-poorer surgical outcomesMarkedly increased RV dimensions-severe TR(associated Ebsteins anomaly %)
16 The aortic arch is left sided Aortic valve stenosis has been described in patients with pulmonary atresia and intact ventricular septum
17 Myocardial Abnormalities Ischemia, fibrosis, infarction, and myocardial rupture have been observedMyocardial disarray and ventricular endocardial fibroelastosis also seen.
18 Ventricular to coronary artery communications PA IVS is associated with ventriculo arterial connections(by large sinusoids)Usually seen in association with hypoplastic RVConnections are seen to commonly RCA,LAD(to LCX is rare)Blood flowSystole-High pressure RV to sinusoidsDiastole-coronary artery to RV- ‘coronary steal'
19 DevelopmentCoronary circulation develops as isolated plexus of vessels.Connections first develop to ventricular cavity and later coronary arteries develop and connect to aorta.Pulmonary atresia-high RV pressure maintains RV to sinusoids patency
24 Natural History Equal prevalence in male and female 50% newborns die in first month of lifeMajority die in first 3 monthsSurvival beyond first year is rare.Survival upto 21 years reported.
25 Physical ExaminationNewborns with pulmonary atresia and intact ventricular septum become cyanotic and hypoxemic –along with closure of the patent arterial ductCyanosis usually is apparent within hours of birth and is progressive
26 The left ventricle may be enlarged, and at the apex, its impulse may be forceful. The second heart sounds is single.(A2)A pansystolic murmur may be audible at the left lower sternal border(of tricuspid regurgitation.)Arterial duct murmur may be heard in the second and third left intercostal space
27 Radiographic Features The chest radiograph may demonstrate a heart that is only mildly enlarged or one that fills the entire chest cavity
28 Electrocardiographic Features Frontal QRS axis of + 30 to + 90paucity of right ventricular forcesleft ventricular dominance or left ventricular hypertrophyRight atrial enlargement
29 The Electrocardiogram in Tricuspid Atresia and Pulmonary Atresia with Intact Ventricular Septum Circulation.1966; 34: 24-37
30 Electrocardiograms were studied in 37 patients with tricuspid atresia and in 20 with pulmonary atresia and intact ventricular septum.The results were correlated with angiocardiographic findings and postmortem examinations
31 Biatrial hypertrophy was noted in 81% of the electrocardiograms in patients with tricuspid atresia, whereas this pattern was seen in only two infants with pulmonary atresia and intact ventricular septum
32 In tricuspid atresia, left axis deviation was more common. Pulmonary atresia - no instances of left axis deviation in the frontal plane.
33 Echocardiographic Features Functional status of the interatrial septum - obligatory right-to-left shunting.The size and morphology of the tricuspid valve ,RVPatency of ductusDegree of TREbsteins anomaly
34 Functional pulmonary atresia Lack of forward flow is due to high pulmonary artery pressure with poor right ventricular function or very severe tricuspid insufficiency. Pulmonary valve is morphologically normal but functionally closed
35 Cardiac cathetrisation Groin approachCatheter passed through IVC to RAEasily passes to LA(PFO)RV entry difficult if severe TR/RV hypoplasiaDuctus visualised by left ventricular angiogramVisualisation of coronary arteriesRV angiogram-ventricular coronary communicationsconfirm PA
37 Management PGE1 infusion to maintain ductal patency Electively intubated and controlled ventilationMetabolic acidosis to be corrected and ionotropic support if perfusion is inadequateAdequately stabilized before any initial procedure
38 Surgical managementGoal is to achieve a two ventricular circulation with the right ventricle providing all blood flow to the lungs at a low filling pressures without residual right to left shuntGoal should be achieved withlow moratalitypromoting the growth of RVminimizing the need for subsequent surgical procedures
39 RV cavity size and coronary artery anatomy are crucial in selecting appropriate treatment strategy
40 The options available include the following. Surgical opening of the pulmonary valve and the right ventricular outflow tract.Systemic arterial to pulmonary arterial shuntTranscatheter opening of the pulmonary valve.Maintaining ductus arteriosus patency.Systemic venous to pulmonary arterial shunt.Closing the tricuspid valve.
41 Venous to pulmonary arterial shunts Glenn procedure: end-to-end anastomosis of the SVC to the left pulmonary artery.Cavopulmonary anastomosis or bidirectional Glenn procedure: anastomosis of the SVC to the pulmonary artery so that both lungs can be perfused by SVC blood.Atriopulmonary connection or Fontan procedure:Anastomosis of the right atrial appendage tothe pulmonary artery to divert all venous returninto the pulmonary artery.
42 Surgical pulmonary valvotomy with patch closure Severe pulmonary stenosis or pulmonary atresia with well-developed right ventricle and mild or no tricuspid regurgitationSurgical pulmonary valvotomy with patch closureBalloon valvuloplasty
43 Pulmonary atresia with well-developed right ventricle and marked tricuspid regurgitation SVC to pulmonary artery communication (bidirectional Glenn procedure) can be performed in addition to valvotomy.
44 Pulmonary atresia with hypoplastic right ventricle and tricuspid valve Tricuspid valve diameter less than 8 mm in a newborn infantTricuspid to mitral valve diameter ratio less than 0.7Tricuspid valve diameter Z-scores of –3 or smaller
46 Pulmonary atresia with hypoplastic right ventricle and coronary sinusoids Attempts to open the RVoutflow tract are contraindicated.Systemic-to-pulmonary arterial shunt or prolonged PGE1 infusion is recommended.After the age of 3–4 months, cavopulmonary anastomosis may be performed.
49 Risk factor for death after initial procedure Low birth weightSmall tricuspid valveRV dependent coronary circulation
50 Prognosis and long-term results after procedures Balloon valvuloplasty performed in the neonatal period may not be very effective in relieving stenosis.Cyanosis may persist and repeat valvuloplasty may be necessary within 6–9 months.Residual pulmonary valve insufficiency
51 Pulmonary atresia with intact ventricular septum: Strategy based on right ventricular morphology Naoki Yoshimura, MD, Masahiro Yamaguchi, MD et alJ Thorac Cardiovasc Surg 2003;126
52 Between April 1981 and June 2002, 45 consecutive patients with pulmonary atresia with intact ventricular septum underwent surgical treatment.Open transpulmonary valvotomy was performed in 27 patients and Blalock-Taussig shunt in 18 patients as the initial palliative procedure.Three patients who underwent a successful transpulmonary valvotomy alone in the neonatal period required no further operation.Definitive repair was performed in 32 patients
53 RESULTSThere were 1 early and 2 late deaths before the definitive operation in patients who underwent transpulmonary valvotomy.Two patients who had coronary artery interruption died 3 months and 13 years after the initial Blalock-Taussig shunt.There were 1 early and 2 late deaths after the definitive operation.Survival, including noncardiac death, was 91.1% at 5 years after the initial procedure and 81.5% at 10 years
54 OUTCOME AFTER OPERATIONS FOR PULMONARY ATRESIA WITH INTACT VENTRICULAR SEPTUM Jack Rychik MD, Hara Levy MD et alJ Thorac Cardiovasc Surg 1998;116Overall survivals at 1, 5, and 8 years were 82%, 76%, and 76%.Mortality was highest in infancy
55 Prenatal Diagnosis of Pulmonary Atresia with Intact Ventricular Septum
56 Flow through the foramen ovale- moving from the right atrium to the left atrium. Retrograde flow through the ductus arteriosis