This temporary pacemaker, smaller than a grain of rice, could regulate the heart less invasively
Temporary pacemakers can be used as a stopgap measure to regulate the heartbeat after surgery and in emergency situations. But the fact that they need to be surgically installed and removed also brings risk: moon walker Neil Armstrong famously developed fatal bleeding when surgeons removed his temporary pacemaker's wires in 2012. Now researchers have developed a tiny temporary pacemaker that could eliminate some of that risk. Their device, just a few millimeters long, has no wires and needs minimally invasive placement. It can be injected into the body with a needle. And when its work is done, it simply dissolves. Conventionally, temporary pacemakers comprise electrodes that are implanted in the heart muscle. These electrodes are connected to an external battery that delivers a pulse to control the heart's rhythm and correct slow or irregular heartbeats. The new, less invasive pacemaker, which could be particularly useful in a newborn baby's tiny heart, "consists of two electrodes—conducting metal pads—that are designed to do two things," says Northwestern University biomedical engineer John A. Rogers, one of the co-authors of an April 2 paper in Nature that describes the device. "One is that they inject current into the cardiac tissue to stimulate contractions that lead to an overall cardiac cycle.... [The other is that they] provide a power source for driving the operation of the pacemaker." A temporary pacemaker like this one, smaller than a grain of rice, could be injected into the body to regulate heartbeats. John A.…