Transvenous closure of acquired ventricular septal defects

Post infarction ventricular septal defect is an uncommon but frequently fatal complication of myocardial infarction. In this report a method for creating experimental ventricular septal defects is described and the use of a transvenous balloon catheter for closure of septal perforations reported. Ventricular septal defects were created with a specially designed punch in 25 adult mongrel dogs. Severe hemodynamic compromise occurred immediately following septal perforation in 15 animals which failed to permit sufficient time to pass the transvenous balloon catheter. However, passage of the catheter and occlusion of the ventricular septal defect was accomplished in the remaining 10 animals. Perforation of the ventricular septum resulted in a marked left-to-right shunt as indicated by changes in interventricular pressure and a step-up in the right ventricular PO₂ saturations. Passage of the double balloon catheter and inflation of the balloons prevented left-to-right shunting and completely occluded the ventricular septal defect. Further refinements of this experimental catheter may result in the development of a balloon catheter that may be used to stabilize patients after spontaneous ventricular perforation, thus allowing them to recover from their infarction and undergo delayed repair of the ventricular septal defect.