Assessment of biventricular cardiac function in patients with a Novacor left ventricular assist device.

Novacor left ventricular assist devices were implanted in 10 patients. We used blood-pool radionuclide angiography and echocardiography to evaluate the response of the left and right ventricle to the left ventricular assist. Radionuclide angiography was done before and after implantation of the Novacor left ventricular assist devices in all cases. All patients had diffuse left ventricular enlargement; the mean left ventricular ejection fraction before Novacor left ventricular assist device implantation was 17% +/- 7%. After implantation of the Novacor left ventricular assist devices the left ventricular ejection fraction improved to 47% +/- 19%, with the pump on a 1:1 assist ratio (p < 0.005). The right ventricular ejection fraction before the Novacor left ventricular assist device implantation was 21%, which improved to 32% with the Novacor left ventricular assist devices (p < 0.01). Doppler echocardiography was carried out in nine patients with the left ventricular assist devices. In five patients the aortic valve remained closed throughout systole. In four patients partial aortic valve opening was noted. At an assist ratio of 1:3, complete opening of the aortic valve was noted in all cases (n = 9); the left ventricular ejection fraction decreased to 31%. We conclude that the Novacor left ventricular assist device substantially improves both right ventricular ejection fraction and left ventricular ejection fraction, although the aortic valve typically remains closed.