A tiny pacemaker that doesn't need wires to stimulate the heart has been approved for sale in the European Union. It's the world's first wireless pacemaker to hit the market. This device, which is about the size and shape of a AAA battery, is designed to be inserted into the heart in a non-invasive procedure that would take about a half-hour.
The device was developed by a secretive California startup called Nanostim, which was just acquired by the biomedical device company St. Jude Medical. The company will have to do more clinical trials before the device can be submitted for approval to the U.S. Food and Drug Administration.
Today's pacemakers are already pretty small—about the size of three poker chips stacked up—but to insert one a surgeon has to cut open a patient to install the device near the heart, and then connect the wires, called leads, to provide electrical stimulation to the heart muscle. Those leads are often the source of the problem when pacemakers fail . The tiny wires can fracture or move as the heart beats continuously, and St. Jude has had several pacemakers recalled as a result of faulty leads.
The Nanostim device is put in place via a steerable catheter that's inserted into the femoral artery. The tiny pacemaker is attached to the inside of a heart chamber, where it can directly stimulate the muscle. The animation below (no audio) demonstrates the insertion procedure.
St. Jude says the pacemaker's battery should last for 9 to 13 years, and says that the pacemaker can be removed and replaced in a similar procedure to the insertion.
The market for such a device is large: More than 4 million people worldwide now have a pacemaker or a similar device to manage their cardiac rhythms, and 700 000 new patients receive such devices each year.
Image and animation: St. Jude Medical