Organic and functional pulmonary atresia with intact ventricular septum

Pulmonary atresia in prenatal life

Seven cases of pulmonary atresia with intact ventricular septum were detected in prenatal life. In two of these cases, there was a small hypertrophied right ventricle of the type commonly seen postnatally. In the remaining five cases, the right atrium and right ventricle were grossly dilated to a degree that caused lung compression. The resulting impairment of lung development appeared to be an important factor contributing to death in all five cases. Decompression of the right ventricle by intrauterine surgery to allow normal lung development in the last weeks of pregnancy may be the only way of changing this outcome.

Functional aortic valve atresia in transposition of the great arteries

The criterion for the diagnosis of functional atresia of a patient semilunar valve is met when the pressure in a ventricle remains lower than that in the related great artery throughout systole so that no forward flow can occur. Functional pulmonary valve atresia has been well recognized in infants with normally related great arteries and massive tricuspid valve incompetence. The cardiac physiology and anatomy of an infant with transposed great arteries and functional aortic valve atresia is reported for the first time. The peak systolic pressure in the right ventricle was 30 mm Hg and in the aorta 64 mm Hg. The causes for right ventricular incompetence were abnormalities of the tricuspid valve and hypoplasia of the ventricular free wall. Three other cases with similar ventricular anatomy and physiology but with anatomic atresia of the aortic valve are reviewed. The possibility that under these physiologic circumstances during fetal life functional atresia develops first, and that anatomic fusion of idle semilunar cusps develops as a secondary phenomenon, is discussed.

Right ventricular infarction with cardiac rupture in an infant with pulmonary valve atresia with intact ventricular septum

This report describes an 8 day old infant with pulmonary valve atresia, hypoplastic and hypertensive right ventricle and myocardial sinusoid-left anterior descending coronary artery connections. A large right ventricular sinusoid complex developed that was associated with transmural right ventricular necrosis and cardiac rupture. This is the first report to document transmural myocardial infarction and rupture in pulmonary valve atresia with intact septum, and this condition should be added to the causes of myocardial infarction in infancy. A reduced number of caliber of sinusoid-coronary artery channels may be responsible for right ventricular damage in this condition.

Pulmonary atresia with and without ventricular septal defect: a different etiology and pathogenesis for the atresia in the 2 types?

In 15 of 20 hearts of neonates with pulmonary atresia and intact septum (PA-IVS) and in 4 with critical pulmonary stenosis, the pulmonary valve consisted of 3 fused cusps. One of the 11 patients with a ventricular septal defect (PA-VSD) had a well-developed pulmonary root; in 8 the pulmonary trunk arose from a dimple. Two had a bicuspid valve. In 10 of the 20 patients with PA-IVS and in those with critical stenosis, the diameter of the pulmonary trunk was normal or larger than normal. The authors believe that this is related to flow through an initially patent pulmonary valve and, perhaps more importantly, to poststenotic dilatation. In all hearts with PA-VSD, the pulmonary trunk was very small. In the patients with PA-IVS and a normal-sized pulmonary trunk and in 3 with critical pulmonary stenosis, the morphology of the ductus arteriosus was normal, suggesting that even in the former the valve was patent before birth, allowing forward flow. In all patients with small pulmonary trunk, the ductus was long, tortuous, and originated from the aortic arch in a proximal position, suggesting that reversal of flow had occurred early in development. The authors postulate that in patients with ventricular septal defect (VSD), the pulmonary ostium becomes atretic early in development, at or shortly after partitioning of the truncoconal part of the heart has taken place but before closure of the ventricular septum. In patients with intact ventricular septum, on the other hand, atresia very likely occurs sometime after cardiac septation has been completed. In these cases the pulmonary atresia may be due to a prenatal inflammatory process, rather than representing a true congenital malformation.

Right ventricular volume determinations in 18 patients with pulmonary atresia and intact ventricular septum. Analysis of factors influencing right ventricular growth

Right ventricular growth was assessed angiocardiographically in 18 patients with pulmonary atresia, intact ventricular septum, and hypoplastic and hypertensive right ventricle. A variety of surgical procedures were performed. In only 12 patients (66.7%) was right ventricular-pulmonary artery continuity achieved (group 1). Nine of these 12 patients persisted with systemic or suprasystemic right ventricular pressures. Among the six patients in whom right ventricular-pulmonary artery continuity was not achieved (group 2), all maintained suprasystemic right ventricular pressures. Right ventricular growth was assessed in groups 1 and 2. The patients were also subdivided according to the qualitative degree of tricuspid regurgitation as determined angiocardiographically on right ventricular cineangiocardiograms at the preoperative catheter study. Right ventricular growth to normal levels as evidenced by change in right ventricular end-diastolic volume was rarely observed in group 2 patients. Among the four patients with severe tricuspid regurgitation and a large tricuspid valve, right ventricular growth to normal levels was achieved whether they were in group 1 or group 2. Right ventricular growth is thus predicated on numerous morphologic factors in these patients. However, reconstitution of right ventricular-pulmonary artery continuity and a nonobstructive tricuspid valve are probably two of the more important factors.

"Balloon valvulotomy" of congenital pulmonary valve stenosis with tricuspid valve insufficiency

The rare congenital anomaly of pulmonary valve stenosis and massive tricuspid valve insufficiency with intact ventricular septum is a lethal condition without reported survival after attempted treatment. In a neonate suffering from this syndrome, the pulmonary valve stenosis was relieved by rupturing the fused valve with a balloon catheter introduced transvenously. The desperate condition of the patient quickly improved after this procedure, with subsequent disappearance of the tricuspid valve incompetence. Balloon rupturing of fused valves at angiography may represent a therapeutic alternative in cases in which surgical valvulotomy is associated with a high mortality.

Severe congenital tricuspid incompetence in the neonate

Five neonates with congenital tricuspid incompetence due to severe tethering of the tricuspid valve to the right ventricle by abnormal chordal and papillary muscle attachments are described. The abnormality was called tricuspid valvular dysplasia (TVD) if the basal insertion of the valve was normal and the Ebstein malformation if it was displaced into the sinus portion of the ventricle.

In the two infants with isolated TVD and severe tricuspid regurgitation the functional obstruction to right ventricular outflow (ORVO) produced by the high perinatal pulmonary vascular resistance (PVR) made the exclusion of pulmonary atresia difficult, despite selective right ventricular angiocardiography.

In three infants the tricuspid valvular abnormality was associated with organic ORVO; pulmonary atresia in two and critical pulmonary valve stenosis in one. In the two infants with pulmonary atresia and intact ventricular septum (IVS) the severe tricuspid incompetence produced a clinical, radiological and hemodynamic profile which was clearly different from that usually seen in infants with pulmonary atresia and IVS and a normal right ventricular cavity (type 2 of Greenwold).

Pulmonary valve atresia with intact ventricular septum. Report of a case with long survival and pulmonary blood supply from an anomalous coronary artery

A case of pulmonary valve atresia with intact ventricular septum' with long survival in the absence of a patent ductus arteriosus, is presented. The patient, alive at 21 years of age, has the anterior descending branch of the left coronary artery originating from the pulmonary artery. Thus, the pulmonary blood supply is obtained from the right coronary artery via intercoronary anastomoses. No similar case has been reported previously.