Wireless pacemaker could improve heart regulation

A wireless pacemaker system has been developed that could lead to more effective heart regulation and make implantation surgery easier.

The device, which eliminates the risk of leads implanted in the heart from failing, uses sonic pulses to transmit energy to an electrode in the left ventricle that converts it into electricity and applies it to the muscle tissue.

California-based EBR Systems has developed the Wireless Cardiac Stimulation (WICS) system in collaboration with UK company Cambridge Consultants, which helped turn the idea into a commercial product.

Andrew Diston, head of global medical technology practice at Cambridge Consultants, told The Engineer that, although failure rates among existing pacemakers were low, the consequences of lead failure could be fatal for users.

‘The leads provide the electrical energy that causes the muscle to contract, but like all leads they are prone to failure, especially when they are exposed to continual movement inside the body,’ he said.

Current technology requires electrodes to be placed on both the left and right sides of the heart, connected to the pacemaker device by three leads.

One of these has to be threaded through a complex route running from inside the right atrium, out of the heart and positioned on the left ventricle.

‘This particular product eliminates the lead completely; it simplifies the delivery and implantation of the system and means you can put the electrode in a place where it can better mimic the body’s natural electrical-to-muscle movement,’ said Diston.

The system still makes use of traditional technology to determine when electrical stimulation is needed and to supply electricity to the right side of the heart, which should make it easier to achieve regulatory approval.

A separate pulse generator monitors electrocardiogram readings from the heart to detect the action of the traditional pacemaker. It then sends out an ultrasonic pulse to detect the exact position of the wireless electrode, before transmitting a more focused beam of sonic energy that is then converted into electricity.

Diston said the biggest challenge in developing the device was developing the ultra-low-power circuitry that could transmit sufficient energy in such a small space.

The device is now undergoing human trials in Europe in preparation for certification.