Abstract
Intraventricular axial flow blood pumps, Jarvik 2000 designed for long term left ventricular assist, were implanted in seven calves. Six calves have survived for 63 to 162 days (mean 110 days). One study is ongoing at 74 days. The causes of termination of study were broken electrical wire in one case, thrombus at rotor/stator junction in one case, impeller blade/casing rubbing in three cases and obstruction of outlet conduit in one case. Plasma free hemoglobin and other laboratory data were observed in normal range. No damage of myocardium and no renal infarction were observed after over five month survival.