More than 20 years ago, Terri Mattula’s dog Gator passed out while her husband was walking him. They took Gator to the vet and learned he had a third-degree heart block and needed a pacemaker. However ...
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 ...
Your heart has an internal pacemaker called the sinus node. It's a group of cells, located on top of your heart, that sends electrical signals into the heart and controls your heartbeat. Sometimes, ...