In the 58 months from January 1, 1975 to October 31, 1980, 23 patients required assisted circulation pre- or past-cardiopulmonary bypass. Six patients (268) were successfully weaned from the assisted circulation and survived.
Veno-arterial bypass (VAB) without intraaortic balloon pumping (IABP) was performed in 15 patients, and it was effective in 3 patients. In two of them, the cause of low cardiac output was removed surgically after VAB and a patient with intractable ventricular fibrillation which occured in ICU was defibrillated under VAB.
Eight patients who showed myocardial injuries after open heart surgery or coronary revascularization underwent VAB and IABP and only three patients demonstrated adequate responses and survived operation.
These data suggested that VAB with IABP might be ineffective for patients who had severe myocardial injuries after cardiopulmonary bypass and we expect the left ventricular assist device will offer a great help in these cases.