A pacemaker produces electrical impulses that stimulates the heart to beat in a regular rhythm. A pacemaker senses when the heart beats irregularly and sends a signal to the heart that makes the heart beat at the correct pace. A doctor surgically implants a pacemaker under the skin, usually on the left side of the chest, just below the collarbone. Doctors recommend pacemakers for people who have certain types of heart problems.
Slow Heart Beat
According to the National Heart Lung and Blood Institute, a doctor may recommend a pacemaker for an individual who has the heart problem called bradycardia. Bradycardia, or a slower-than-normal heartbeat, can occur from certain conditions affecting the heart or from heart medicines, such as beta blockers. Beta-blockers may slow the heartbeat too much and the medication may contribute to the placement of a pacemaker. Bradycardia causes the symptoms of lightheadedness, tiredness, fainting spells and shortness of breath because the slower-than-normal heartbeats result in less oxygen for the body and the brain.
Arrhythmias
A pacemaker can correct arrhythmias, or irregular heartbeats. The American Heart Association explains that a pacemaker regulates arrhythmias by sending impulses that flow at regular intervals through the leads to the heart. A pacemaker can sense if the heart beats above the programmed rate, and it regulates the heartbeats by not sending the signals to the heart that tell it to beat faster. A pacemaker can also sense when the heartbeat slows below the programmed rate, and it automatically turns back on and starts pacing the heartbeat again.
Heart Muscle Problems
Normal aging or heart disease can damage the heart muscle, leading to the placement of a pacemaker, notes the National Heart Lung and Blood Institute. Damage to the heart muscle disrupts the hearts natural ability to set the correct pace for a regular heartbeat. The damage can cause heartbeats to alternate between slow and fast rhythms. A heart block affects the heart's electrical system and can happen as a result of normal aging, damage to the heart, or other conditions that interfere with the heart's electrical activity. With heart block, a slower-than-normal heartbeat occurs because the electrical signals travel too slowly through the heart muscle.
