Heart rate determination based on VAD current waveform

A method of determining heart rate of a patient having an implantable blood pump, comprising:

• measuring a motor current signal of the implantable blood pump, the implantable blood pump being in fluid communication with a ventricle of the patient's heart;
• detecting a first event in the measured current signal, the first event being indicative of one from the group consisting of a rise in the current signal and a fall in the current signal;
• initiating a timer counter when detecting the first event;
• detecting a second event in the measured current signal, the second event being indicative of one from the group consisting of a rise in the current signal and a fall in the current signal in the opposite direction as the first event;
• detecting a third event in the measured current signal, the third event being indicative of one from the group consisting of a rise in the current signal and a fall in the current signal in the same direction as the first event;
• measuring an elapsed time of the timer counter when detecting the third event;
• filtering the motor current signal to create a filtered signal, and having the first, second, and third events be detected using a combination of the unfiltered motor current signal and the filtered signal;
• and
• determining the heart rate of the patient based on the elapsed time of the timer counter.