A cardiac pacemaker is a small medical device that's placed in the chest or abdomen to help control abnormal heart rhythms.
This device uses electrical pulses to prompt the heart to beat at a normal rate. Pacemakers are used to treat arrhythmias (ah-RITH-me-ahs). Arrhythmias are problems with the rate or rhythm of the heartbeat.
It generates electrical impulses delivered by electrodes to cause the heart muscle chambers to contract and therefore pump blood; by doing so this device replaces and/or regulates the function of the electrical conduction system of the heart.
The primary purpose of a pacemaker is to maintain an adequate heart rate, either because the heart's natural pacemaker is not fast enough, or because there is a block in the heart's electrical conduction system.
Modern pacemakers are externally programmable and allow a cardiologist, particularly a cardiac electrophysiologist to select the optimal pacing modes for individual patients. A specific type of pacemakers called defibrillator combines pacemaker and defibrillator functions in a single implantable device, which should be called only defibrillator, for clarity. Others, called biventricular pacemakers have multiple electrodes stimulating differing positions within the lower heart chambers to improve synchronization of the ventricles, the lower chambers of the heart.
When does a doctor recommend a pacemaker?
Your doctor also may recommend a pacemaker in one or more of the following cases:
If your sinus node's ability is damaged due to aging or heart disease, to set the correct pace for your heartbeat, as such damage can cause below normal heartbeats or long pauses between heartbeats. The damage also may cause your heart to switch between slow and fast rhythms. This condition is called sick sinus syndrome.
You need to take certain heart medicines, such as beta blockers, as these medicines may slow your heartbeat significantly.
Symptoms of a slow heartbeat or fainting, as such cases can happen if the main artery in your neck that supplies your brain with blood is sensitive to pressure, and you move your neck trying to release tension, as a result, your brain might not get enough blood flow, causing you to feel faint or collapse.
You have heart muscle problems causing electrical signals to slow while traveling through your heart muscle. Your pacemaker can 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.
In addition to the mentioned cases here above, your doctor also may recommend pacemakers for people who have certain types of congenital heart disease or who have had heart transplants. Pacemakers can be used for adults, children and teens.
Before recommending a pacemaker, your doctor will assess any arrhythmia symptoms you have, including but not limited to dizziness, unexplained fainting, or shortness of breath.
Your doctor also will assess your case whether you have a history of heart disease, any medicines you're currently taking, and the results of latest heart tests performed.
The tests performed to assess if you would need a pacemaker are:
An EKG is a simple, painless test that detects and records the heart's electrical activity. The test shows how slow or fast your heart is beating and its rhythm (steady or irregular).
An EKG test also records the level and timing of electrical signals while traveling through your heart.
The test can help diagnose bradycardia and heart block (the most common reasons for needing a pacemaker).
Your doctor may have you wear a portable EKG monitor for a more accurate assessment of diagnose heart rhythm problems, as a standard EKG only records the heartbeat for a few seconds, and it won't detect arrhythmias that don't happen during the test.
Echocardiography (echo) uses sound waves to create a moving picture of your heart. The test shows the size and shape of your heart and how well your heart chambers and valves are functioning.
Echo test also will show areas of poor blood flow to the heart, areas of heart muscle that aren't responding as it should, and any injury to the heart muscle as a result of poor blood flow.
In this test, a thin, flexible wire is passed through a vein in your upper thigh or arm to your heart. The wire records the heart's electrical signals.
Your doctor uses the wire to electrically stimulate your heart. This allows to see how your heart's electrical system functioning, and helps pinpoint where the heart's electrical system is damaged.
Some heart problems are easier to diagnose when your heart is working hard and beating fast.
During stress testing, the exercises given to you will make your heart work harder and beat faster while heart tests, such as an EKG or echo, are done.
If you can't exercise, you may be given medicine to raise your heart rate.
Generally, pacemaker implantation surgery is safe. In rare cases, some problems may occur, it may include:
Swelling, bleeding, bruising, or infection in the area where the pacemaker was placed
Blood vessel or nerve damage
A collapsed lung
A bad reaction to the medicine used during the procedure
Discuss with your doctor about all benefits and possible risks of pacemaker implantation surgery.