Abstract
Highly reliable pneumatic artificial heart (AB) driving system with complete redundant system for failure free operation was developed and used in 13 left ventricular (LV) bypass experiments without any failure. It has the following features besides normal counterpulsation; (1) When the contraction of LV is detected during pump systole, AH is quickly switched to diastolic phase. In tachycardia, if systolic time of AH becomes too short to eject enough blood flow, the next ejection begins earlier and continues longer. (2) When the diastole of LV continues for longer than 1+ seconds, AH starts the pumping. (3) In fibrillation, AH is asynchronously pumped.
