Results with the Novacor assist system and evaluation of long-term assistance.

Abstract

The great number of patients awaiting heart transplant and the shortage of donors has led to the increasing use of left ventricular assist devices (LVAD) for those patients that cannot wait only on medical therapy. In this study we analyze our experience in order to evaluate the possibility of long-term assistance. We have implanted LVAD Novacor in 36 patients with a mean age of 50.4 years. They were all critical candidates for transplant on high doses of inotrops. We evaluated the clinical and hemodynamic results and studied statistically the relative risk of complications at different time intervals of support. In all cases we had a statistically significant improvement of: cardiac output, wedge pressure, pulmonary vascular resistance and mean pulmonary pressure. Eleven patients died on the device, 23 underwent heart transplant and two are still on the device. Causes of death were mostly related to cerebrovascular events or multiorgan failure. Seven of the 23 patients who underwent heart transplant died with a survival rate after transplant of 69.5% and an overall survival rate of 50%. Complications occurred in 33 patients with: 24 strokes, eight TIAs, four cerebral hemorrhages, three peripheral embolisms, seven cable infections, two pocket infections, two sepsis, two major lung infections, one mediastinitis, one right ventricular failure and three multiorgan failure. Time-related analysis showed that these complications occurred mostly during the first 3 months of assistance and this is particularly true for cerebrovascular events. The incidence of infections remained constant during the follow-up period. With a mean time of assistance of 203.1 days we had only two cases of device malfunction at 662 and 1297 days. LVAD Novacor has provided reliable mechanical performance and good hemodynamic improvement. Most complications seem to occur in the first 90 days, therefore long-term assistance could be considered. A reduction of the high rate of thromboembolic complications remains mandatory to improve the clinical results.