Analysis of platelet function during left ventricular support with the Incor and Excor system

Improvements in pump technology and the scarcity of donor organs have led to an increased use of mechanical assist devices, but the problem of thromboembolism has still not been solved. We report on our initial experience with sequentially analyzing platelet function in patients provided with the Incor left ventricular assist device (LVAD) and the Excor LVAD system. Thirteen patients 5 to 61 years old with acute or end-stage heart failure were included in a pilot study. Five of the 10 Incor patients underwent LVAD placement under emergency conditions, and 5 were electively scheduled for surgery. All 3 patients with an Excor device had been connected to an extracorporeal membrane oxygenation system prior to insertion of the device. An anticoagulation protocol including heparin, aspirin, and clopidogrel was employed, and the patients were closely monitored with a special platelet-analyzing system that allows dose optimization for antiplatelet drugs. Initial platelet function was normal in only 2 patients (15%). During a follow-up period of 1770 days (cumulative >4.8 years), no early(<30 days) bleeding complications related to device implantation occurred. Late cerebral thromboembolic events were noted in 3 patients. One patient experienced severe stroke mandating neurosurgery during mechanical assist, and 1 patient experienced systemic embolism. The PAP platelet analyzer offers a cheap and reliable alternative to the more expensive thromboelastography method for adequately surveying the efficacy of aspirin and clopidogrel treatment, even if late thromboembolic events cannot be prevented.