On the horizon: An ICD that works without wires
Implantable cardioverter-defibrillators (ICDs) are small devices that detect potentially deadly heart rhythms, stop them with an electric shock, and restore a normal heart rhythm. Although ICDs are generally implanted in older people who have survived a heart attack, another use is in younger people whose seemingly healthy hearts lapse into the fast or erratic rhythms known as ventricular tachycardia and ventricular fibrillation.
Traditional ICDs are connected to the heart via thin wires called leads (pronounced leeds) placed through a large vein and then into the heart. Placing the leads through the vein is one of the trickiest parts of the procedure, and leads sometimes fail.