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Epidemiology
Morphology
This particular malformation entails the association of atresia of the pulmonary valve, a tetralogy-type VSD, and pulmonary collateral vessels that usually originate from the descending thoracic aorta.
Clinical features
Neonates born with PA, VSD, and MAPCAs may have very unpredictable presentation owing to the anatomic variability of the lesion. Patients may be minimally symptomatic or severely cyanotic, or may develop congestive heart failure (CHF) from pulmonary overcirculation.
Diagnosis
Diagnostic evaluation includes echocardiography, cardiac catheterization, and, in selected cases, computed tomographic angiography (CTA) to clarify the anatomy of the MAPCAs.
Treatment
Definitive treatment is surgical. The ultimate goal of surgical therapy is creation of separated, in-series pulmonary and systemic circulations. Achievement of this goal requires unifocalization of the vascular systems, VSD closure, and reconstruction of the right ventricular outflow tract (RVOT). “Single-stage” unifocalization with or without concurrent VSD closure is favored by the authors.
Outcomes
In over 460 patients managed by the authors’ protocol, complete unifocalization via median sternotomy was achieved in 76 percent of patients. Intracardiac repair (VSD closure) was possible at initial operation in 56 percent. Ninety-five percent of patients were completely repaired by 5 years of age. Recent operative mortality was 2.3 percent, with a 5-year actuarial survival of 85.5 percent.
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Introduction and Background
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Pulmonary atresia (PA) with ventricular septal defect (VSD) and major aortopulmonary collateral arteries (MAPCAs) is a complex lesion with great morphologic variability. The lesion is characterized by atresia of the pulmonary valve, a tetralogy of Fallot-type VSD, and pulmonary collateral vessels originating from the aorta. The major variability occurs in the pulmonary vascular circulation. Development of the pulmonary arterial system occurs by fusion of the left and right sixth dorsal aortic arches with the plexus of systemic arteries carried by the lung buds from the foregut. Failure of the normal fusion process results in PA. Development of the true pulmonary arteries (PAs) is variable and depends on the point in gestation at which connection of the lumen of the true PAs with the right ventricle (RV) is lost.1 True central PAs vary from normal size to absent. The mean diameter of the central PAs in the author’s series of over 300 patients was 1.5 mm. A small central confluence is usually present. When confluent PAs are present, there is typically no ductus arteriosus. When the right and left main PAs are discontinuous, bilateral ducti may exist with the right typically originating from the innominate or subclavian artery.
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Persistent connections from the aorta (MAPCAs) probably originate from splanchnic vessels. Collaterals vary widely in origin, course, size, and histologic appearance. The mean number of collaterals in the author’s series was 3.8 ± 1.4. ...