Who Uses a Cardiac Pacemaker?
Cardiac pacemakers are used by sufferers from “bradycardia” and “heart-block”. Bradycardia is a heartbeat that is slower than normal. Heart block is a disorder that occurs if an electrical signal is slowed or disrupted as it moves through the heart.
They do the work normally performed by the body’s natural pacemaker in controlling the rate and rhythm of the heart beats. This natural pacemaker is a small collection of specialized nervous tissue situated at the base of the heart. It forms the starting point for the impulses that initiate the heartbeats.
“Heart-block” is a serious condition in which the conducting mechanism between the cavities of the heart (atrium and ventricle) is impaired or destroyed. When this happens, the atrium and ventricle beat at different rates independently of each other because the impulse from the pacemaker is not reaching all parts of the heart.
Heart block can happen as a result of aging, damage to the heart from a heart attack, or other conditions that disrupt the heart’s electrical activity. Some nerve and muscle disorders also can cause heart block, including muscular dystrophy.
Fainting, convulsive attacks or complete stoppage of the heart may follow, but the condition can be overcome by the use of an artificial pacemaker. This acts as a battery to stimulate the heart, allowing it to beat regularly at normal speed, about 70-80 impulses a minute.
The pacemaker is either fixed to the outside of the chest or implanted in the armpit and connected to an electrode tube, which is passed through the main vein in the neck into the heart.
Your doctor also may recommend a pacemaker if:
- Aging or heart disease damages your sinus node’s ability to set the correct pace for your heartbeat. Such damage can cause slower than normal heartbeats or long pauses between heartbeats. The damage also can cause your heart to switch between slow and fast rhythms. This condition is called sick sinus syndrome.
- You’ve had a medical procedure to treat an arrhythmia called atrial fibrillation. A pacemaker can help regulate your heartbeat after the procedure.
- You need to take certain heart medicines, such as beta blockers. These medicines can slow your heartbeat too much.
- You faint or have other symptoms of a slow heartbeat. For example, this may happen if the main artery in your neck that supplies your brain with blood is sensitive to pressure. Just quickly turning your neck can cause your heart to beat slower than normal. As a result, your brain might not get enough blood flow, causing you to feel faint or collapse.
- You have heart muscle problems that cause electrical signals to travel too slowly through your heart muscle. Your pacemaker may provide cardiac resynchronization therapy (CRT) for this problem. CRT devices coordinate electrical signaling between the heart’s lower chambers.
- You have long QT syndrome, which puts you at risk for dangerous arrhythmias.
Doctors also may recommend pacemakers for people who have certain types of congenital heart disease or for people who have had heart transplants. Children, teens, and adults can use pacemakers.
Before recommending a pacemaker, your doctor will consider any arrhythmia symptoms you have, such as dizziness, unexplained fainting, or shortness of breath. He or she also will consider whether you have a history of heart disease, what medicines you’re currently taking, and the results of heart tests.