Patent attributes
A ventricular assist device incorporating a rotary pump, such as a rotary impeller pump is implantable in fluid communication with a ventricle and an artery to assist blood flow from the ventricle to the artery. The device includes a pump drive circuit supplying power to the pump, one or more sensors for sensing one or more electrophysiological signals such as electrogram signals in and a signal processing circuit connected to the sensors and the pump drive circuit. The signal processing circuit is operative to detect the sensor signals and control power supplied to the pump from the pump drive circuit so that the pump runs in a pulsatile mode, with a varying speed synchronized with the cardiac cycle. When an arrhythmia is detected, the pump drive circuit may also run the pump in an atrial arrhythmia mode or a ventricular arrhythmia mode different from the normal pulsatile mode.