A pacemaker without wires

A pacemaker that regulates the heart by wirelessly zapping it with pulses of ultrasound from outside the organ is currently undergoing human trials in Europe.

Conventional pacemakers stimulate the heart tissue via electrical leads that are fed into the heart through a vein. But leads can fail, requiring additional surgery to remove and replace them. The conventional approach also restricts where the therapeutic shock can be delivered.

The new device uses focused acoustic waves that are picked up by a small receiver implanted permanently inside the heart, converting the energy into electricity. Unlike radio waves, ultrasound can pass through tissue at high-enough energy levels without causing any heating.

"This represents a significant breakthrough, eliminating the lead in the heart," says Paul Skjefte, marketing strategist for EBR Systems, the company that created the pacemaker. The startup, based in Sunnyvale, California, was spun out of research by founder Debra Echt, a former professor of medicine and a cardiologist at Vanderbilt University.

A report in Technologyreview. Here