Feasibility of using the automatic generating system for quartz watches as a leadless pacemaker power source

Abstract

An automatic power-generating system (AGS) which converts kinetic energy into electric energy for quartz watches was tested as a power source for implantable cardiac pacemakers. An automatic power-generating mechanism and a capacitor (0.33 F) were removed from a quartz watch (SEIKO) and encapsulated in a polyvinyl case. Characteristics of the AGS were investigated by acceleration equipment. The capacitor in the AGS was charged to 2.0 V (0.66 J) by placing it on the equipment for about 30 minutes. The equipment has a 2 Hz cycle and generates +/- 1.7 G at the end of each half cycle. The AGS (fully charged to 2.0 V) was used as the power source for a pulse generator circuit built using commercially available CMOS IC. The circuit generated pulses of 0.5 ms width at 1 Hz (60 pulses min-1). The voltage of the AGS was maintained at 1.6 V while it was being charged by the accelerations. The generator supplied pulses of 0.75 V, 1.47 mA through a 510 omega load. With fully charged AGS, the generator was also used to pace a mongrel dog's heart at 140 beats min-1 for 60 minutes. During pacing, the AGS supplied 420 mJ to the circuit and the cardiac muscle. The AGS was placed on the right ventricular wall of the mongrel dog under anaesthesia. Energy of 80 mJ is stored in a capacitor by the heart beating at about 200 beats/min for 30 minutes. Thus the AGS generated 13 microJ per heart beat. This result suggests that the AGS may supply enough energy for use in a cardiac pacemaker.

Energy Harvesting and Remote Powering for Implantable Biosensors

“…The approach of Seiko has also been successfully tested in the biomedical field, being able to exploit the heartbeats to charge a pacemaker battery [13]. Implanted on a dog, this energy harvester has collected 80 mJ after 30 min with a cardiac frequency of about 200 beats/min: around 13 J per beat with a returned power of about 44 W. A possible drawback of this technique is the necessity to periodically lubricate the moving parts which, in the end, need to be replaced when worn out.…”

A Contemporary Survey on Energy Harvesting Techniques for Next Generation Implantable Bio-Medical Devices

“…AGS was extended to use in pacemaker applications. In [17], it is estimated that with a heartbeat rate of 200 beats per minute (bpm), 80 mJ is generated in 30 minutes, i.e., 13 μJ per heartbeat. This amount of harvested energy is sufficient to pace a mongrel dog.…”

A review: flexible, stretchable multifunctional sensors and actuators for heart arrhythmia therapy

“…Energy harvesting may be done by various methods and all kinds of energy harvesting principles are studies by researchers. Some people are trying to obtain energy using a fuel cell by a chemical reaction between glucose and oxygen, and many people are trying to harvest substantial amount of energy from various mechanical body movements including a knee, body movement, and even a heart wall movement from the heartbeats [38,[42][43][44][45][46][47][48]. Fig.…”