In Vivo Evaluation of the Biocompatibilty of a Totally Implantable Vad (Heartsaver Vad)

Purpose: A series of multi-centre in vivo studies have been conducted to assess biocompatibility and device performance of the HeartSaver VAD, a totally implantable pulsatile VAD. Methods: The first series of experiments (n = 13) were conducted in bovine (10 Holstein, 2 Ayreshire, 1 Hereford) with a mean weight of 99 Kg (75–152 Kg). Two implantation techniques were utilized, one with cardiopulmonary bypass, and one without. Device function and biochemistry was monitored and explant histopathologic analysis conducted. Results: The mean duration ot device support was 37 days 10–91 days). Mean device flow was 6.4 L/min (3.8–8.8 L/min). None of the 13 cases presented thrombosis inside the pump or life threatening infections. No severe bleeding occurred after 24 hours post-operatively. The mean plasma free hemoglobin (5.3 +/−2.5 mg/dl) indicates a clinically acceptable level of hemolysis. Renal and hepatic functions were normal (mean creatinine0.8 +/−0.1 mg/dl and mean ALT 14.6 +/−4.5 mg/dl) in all experiments. Several device related improvements were identified and have been implemented. Additional implants with an optimized device are underway in preparation for human trials.