Experimental and Clinical Observations On the Closure of Cardiac Septal Defects

Abstract

Cardiac septal defects, like many conditions for which no corrective treatment has been available in the past, are inadequately understood both from the standpoint of diagnostic criteria and the life history of those afflicted with these anomalies. It appears that small defects of the atrial and ventricular septa are reasonably well tolerated. Large defects, on the other hand, are associated with varying degrees of cardiac dysfunction and ultimately premature death.Once my associates and I had demonstrated to our satisfaction that we could produce experimentally large atrial septal defects which tended to remain widely patent over long periods of time and which were strikingly like those encountered in patients (1), we investigated a variety of methods for their surgical closure (2). One method seemed ideal. It involved suturing to an incision in the right atrial wall roughly parallel to the interatrial groove a half-moon shaped pocket of autogenous pericardium which could then be invaginated into the atrial cavity. The posterior wall of the pocket could be pushed against the septum so as to permit clear palpation of the defect and careful suturing of the pericardium to the rim of the defect. It could be performed with regularity and without mortality. It did not interfere with cardiac function, produced no significant electrocardiographic alterations, and could be accomplished in a dry field without loss of blood and without hazard of air embolism or intracardiac thrombosis. The grafts all survived and became firmly united with the septum. Closure was complete in nearly all instances, and in the exceptional cases there remained only an inconsequential tiny defect one millimeter in diameter. The ostia of the venae cavae and the coronary sinus were never obstructed. The method seemed eminently suitable for use in human patients.The operation as finally developed was used in two severely ill children who tolerated the procedure well (3). One has shown gratifying clinical improvement in spite of the fact that she also has a known ventricular septal defect and in spite of the fact that postoperative catheterization studies suggest the persistence of a left-to-right atrial shunt. The other child died suddenly 5 months after operation, and, to our amazement, postmortem examination showed the pericardial graft to have disentegrated and disappeared completely from the region of the defect. It then became evident that, in contrast to our experience in dogs, one could not rely upon survival of autogenous pericardium in cases of large human septal defects, presumably because of failure of sufficiently rapid vascularization of the graft. It seemed likely, however, that the operation could be at FLORIDA INTERNATIONAL UNIV on July 12, 2015 ang.sagepub.com Downloaded from