Results of acute and chronic experiments with assisted and total artificial heart

Abstract

An assisted artificial heart and a total artificial heart were implanted in 108 calves. Two types of assisted artificial heart, a bladder type and a diaphragm type made of sflastic and segmented polyurethane, were tested in left atrial (LA) or left ventricular (LV) to abdominal aorta bypass. Of 40 calves that received LA bypass, 6 survived for more than 100 hours. Of 35 calves that received LV bypass, 18 survived for more than 100 hours. In the total artificial heart experiments, an oval-or sphere-shaped total artificial heart was implanted in 13 calves after 20 pilot experiments. That longest survival period was 864 hours (about 36 days), and the average survival time was 8.5 days.Encouraged with recent advances in development of an artificial heart reported elsewhere, we initiated a 5-year research program in 1974. During this period we developed a method for simple ventricular bypass support that was reliable for up to 7 weeks (1-3). Our present aim was permanent circulatory assistance or replacement with an implantable assisted or total heart. This paper presents a summary of our studies in a series of experiments involving 108 calves until August of 1977.