Joseph Akar, MD, PhD, is director of Yale Medicine’s Electrophysiology and Cardiac Arrhythmia Program. As an electrophysiologist, he treats the “electrical wiring” of the heart, which he describes as being not unlike the wiring in a house. The system must work properly, but the electricity in one of the chambers could get disrupted, he says. Heartbeat sequences that are too fast or slow—or otherwise irregular—can lead to serious problems, including stroke and sudden cardiac death. “It’s very important for the heart to have a uniform and consistent rhythm,” he says.