During an average lifetime, the heart beats more than 2 billion times. To you, it might just be a steady “lub-dub” that speeds up under pressure and slows as you drift to sleep. But behind that rhythm ...

The heart may be small, but its rhythm powers life. When something throws that rhythm off—especially after surgery—it can become a race against time to restore balance. For decades, doctors have ...

When Aurora Ernzen was just 5 days old, doctors performed surgery to insert a pacemaker in her chest. The device was new, permitted through emergency use guidelines from the U.S. Food and Drug ...