A new technique that stimulates heart muscle cells with low-energy light raises the possibility of a future light-controlled pacemaker, researchers reported in Circulation: Arrhythmia & Electrophysiology, a journal of the American Heart Association. “Electronic cardiac pacemakers and defibrillators are well established and successful technologies, but they are not without problems, including the breakage of metal leads, limited battery life and interference from strong magnetic fields,” said Emilia Entcheva, Ph.D., senior author of the study and associate professor of biomedical engineering at Stony Brook University in Stony Brook, New York. “Eventually, optical stimulation may overcome some of these problems and offer a new way of controlling heart function.”