Add Yahoo as a preferred source to see more of our stories on Google. Electrocardiograms, or ECGs, record the electrical activity of your heart. Randy Faris/The Image Bank via Getty Images Your ...

Defibrillators and pacemakers help the heart maintain a regular rhythm. Defibrillators deliver a shock if the heart goes into arrhythmia. Pacemakers use electrical impulses to keep the heart from ...

The implantable pacemaker, a medical marvel that has extended millions of lives since its invention nearly 60 years ago, is getting a 21st century makeover. First came a wireless version; these ...

The human heart is a highly complex pump made of muscle, complete with its own electric power system, supplying the energy and oxygen it needs to function. The heart’s pumping action is regulated by ...