Congenitally malformed hearts from a population of children undergoing cardiac transplantation: comments on sequential segmental analysis and dissection.

Our aim is to examine the types of cardiac malformations found in a population of children undergoing cardiac transplantation, and to discuss a method for examining cardiac explants based on intrinsic morphology. We describe in detail the congenital malformations found in 65 cardiac explants acquired from a population of children over a period of 15 years. The specimens were examined and diagnosed using the method of sequential segmental analysis. The most prevalent type of cardiac malformation was severe obstruction of the left heart (29. 2%), followed by double-outlet right ventricle (15.4%), complete transposition (13.8%), hearts with left-hand ventricular topology (10.8%), ventricular septal defect(s) (9.2%), tricuspid valvar agenesis (4.6%), and tetralogy of Fallot (4.6%). These abnormalities accounted for 87.6% of the specimens studied. We also cataloged the extracardiac malformations found at autopsy in those patients who died despite the transplantation. Extracardiac malformations were identified in 10 of the 19 patients who came to autopsy. Three had heterotaxy syndrome with isomerism of the atrial appendages, one with right and two with left isomerism. Other anomalies included tracheoesophageal fistula, pulmonary sequestration, extrahepatic biliary atresia, duodenal atresia, choanal atresia, and vascular malformations.Our study shows that even the most complicated cardiac malformations can readily be diagnosed in an explanted heart using the segmental approach based on observed morphology.