Total anomalous pulmonary venous connection: Report of 93 autopsied cases with emphasis on diagnostic and surgical considerations

Summary

Total anomalous pulmonary venous connection (TAPVC) is failure of development of the common pulmonary vein, with consequent persistence and enlargement of embryonic collaterals between the lungs and the systemic veins. In the great majority (91 of 93 autopsied cases, 97 per cent), no remnant of the common pulmonary vein was found, supporting the concept of agenesis or involution of the common pulmonary vein. Occasionally, a cordlike strand was found in the location of the common pulmonary vein (in three of 93 cases, 3 per cent), supporting the concept of atresia of the common pulmonary vein.

The order of frequency of the various types of TAPVC was: left innominate vein (“snowman”), 26 per cent; subdiaphragmatic, 24 per cent; coronary sinus, 18 per cent; right superior vena cava, 15 per cent; right atrium, 8 per cent; mixed, 5 per cent; azygos, 2 per cent; and left superior vena cava, 2 per cent. TAPVC occurred without other congenital heart disease (isolated TAPVC) in 62 per cent and with other types of congenital heart disease (nonisolated TAPVC) in 38 per cent. Approximately two thirds of nonisolated TAPVC (23 of 35 cases, 66 per cent) was composed of the heterotaxy syndrome—asplenia (14 cases), rudimentary spleen and polysplenia (eight cases), and heterotaxy with a normally formed spleen (one case). The commonest type of isolated TAPVC was the ‘snowman” (20 of 58 cases, 34 per cent), whereas the commonest types of nonisolated TAPVC were to the right superior vena cava and to the ductus venosus (both eight of 35 cases, 23 per cent). TAPVC directly to the right atrium was always nonisolated (seven cases, 8 per cent). However, in isolated and nonisolated TAPVC, the percentages of supracardiac, cardiac, and subdiaphragmatic were remarkably similar.

Obstruction of the anomalous venous pathway was present in 30 of 58 cases of isolated TAPVC (52 per cent) and their median age at death was only 3 weeks. In the 28 cases of isolated TAPVC without obvious anatomic obstruction of the anomalous venous pathway (48 per cent), the median age at death was 3 months. TAPVC is often a rapidly lethal disease, the median age at death in the total series of 93 cases being only 7 weeks, ranging from stillbirth to 19 years. The various sites of obstruction of the anomalous venous pathway were presented in detail and their angiocardiographic diagnosis was condisered. At catheterization in isolated TAPVC, when pulmonary arterial pressure was systemic or suprasystemic, obstruction of the anomalous venous pathway was present in three quarters of such cases (74 per cent). When pulmonary arterial pressure was less than systemic, obstruction was usually absent (87 per cent). Occasionally the atrial septum appeared to be the only site of obstruction (gradient of 3 to 4 mm. Hg on pullback), as in three of 38 catheterized and autopsied cases of isolated TAPVC (8 per cent). In this situation, balloon atrial septostomy appears to be indicated.

Rare and unique cases found in this series merit mention: intact atrial septum with multiple ventricular septal defects; virtually intact atrial septum due to prominent left venous valve, with hypoplastic left heart; total obstruction of the anomalous venous pathway at the ductus venosus; familial TAPVC; familial asplenia; and a case of asplenia with common AV canal, normally related great arteries, aortic valvular atresia, and double aortic arch.

Surgical correction was considered. The horizontal vein, which is anastomosed to the left atrium, was always present, except in three situations: (1) TAPVC to the right atrium; (2) TAPVC to the coronary sinus; and (3) in one case of mixed TAPVC. In both cases of TAPVC with agenesis of the right lung, vascular compression of the tracheobronchial tree—mimicking a vascular ring—was an important problem and its surgical management was considered. From the anatomic standpoint, TAPVC appears almost always to be surgically correctable.