Answer:
In control heart rate: The impulse starts in a small bundle of specialized cells located in the right atrium, called the SA node. The electrical activity spreads through the walls of the atria and causes them to contract. This forces blood into the ventricles. The SA node sets the rate and rhythm of your heartbeat.
Additional Info
- A pacemaker is a small electrical device that's implanted in the chest or abdomen. It's used to treat some abnormal heart rhythms (arrhythmias) that can cause your heart to either beat too slowly or miss beats. Some pacemakers can also help the chambers of your heart beat in sync.
