[Persistent common trunk. Anatamopathological study of 25 specimen].

In order to inform the pathologic features and their associated anomalies twenty five hearts with common trunk were studied with the segmental sequential system. An anatomico-embryological correlation was made to understand the pathological complex of this malformation. The results were: type I truncus (96%), infundibular ventricular septal defect (96%), displastic truncal valve (28%), ventriculo infundibular fold (92%), left coronary artery arising from the posterior wall of the truncus (75%), right coronary artery arising from their anterior wall (96%), coronary arteries arising from opposite Valsalva sinuses in the tetracuspid valves; the biventricular conection of the truncus was balanced in 60%, prevailing on the right (16%) or on the left (16%) ventricles. Among the associated anomalies there were right aortic arch, interruption of the aortic arch, anomalous origin of the left subclavian artery, vascular ring, aneurysm of the sinus of Valsalva, and absence of the left branch of the pulmonary artery. Developmentally common trunk is explained as a failure of truncoconal septation in the embryonic heart; a migration arrest of neural crest cells is implicated in the Di George syndrome. Knowledge of the anatomic features of common trunk and their associated anomalies, provides the morphological basis to interpret correctly the clinical diagnostic imagenology.