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In this Article

• Pacemaker overview
• What is a pacemaker?
• Understanding the heart's electrical system
• Who needs a pacemaker?
• Diagnostic tests
• How does a pacemaker work?
• What should I expect during pacemaker surgery?
• What should I expect after pacemaker surgery?
• What are the risks of pacemaker surgery?
• How will a pacemaker affect my lifestyle?
• Physical activity
• Ongoing care
• Battery replacement
• Pacemaker At A Glance
• Find a local Cardiologist in your town
• Pacemaker Index

Diagnostic Tests

A number of tests are used to detect arrhythmias. Your doctor may recommend some or all of these tests.

EKG (Electrocardiogram)

An EKG is a simple, painless test that detects and records the heart's electrical activity. The test shows how fast the heart is beating and its rhythm (steady or irregular).

An EKG also records the strength and timing of electrical signals as they pass through each part of the heart. The test can help diagnose bradycardia and heart block (the most common reasons for needing a pacemaker).

A standard EKG only records the heartbeat for a few seconds. It won't detect arrhythmias that don't happen during the test.

To diagnose heart rhythm problems that come and go, your doctor may have you wear a portable EKG monitor. The two most common types of portable EKGs are Holter and event monitors.

Holter and Event Monitors

A Holter monitor records the heart's electrical activity for a full 24- or 48-hour period. You wear one while you do your normal daily activities. This allows the monitor to record your heart for a longer time than a standard EKG.

An event monitor is similar to a Holter monitor. You wear an event monitor while doing your normal activities. However, an event monitor only records your heart's electrical activity at certain times while you're wearing it.

For many event monitors, you push a button to start the monitor when you feel symptoms. Other event monitors start automatically when they sense abnormal heart rhythms.

You may wear an event monitor for 1 to 2 months, or as long as it takes to get a recording of your heart during symptoms.

Echocardiography

Echocardiography (echo) uses sound waves to create a moving picture of your heart. The test provides information about the size and shape of your heart and how well your heart chambers and valves are working.

Echo also can identify areas of poor blood flow to the heart, areas of heart muscle that aren't contracting normally, and injury to the heart muscle caused by poor blood flow.

Electrophysiology Study

For this test, a thin, flexible wire is passed through a vein in your groin (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 him or her to see how your heart's electrical system responds. The electrical stimulation helps pinpoint where the heart's electrical system is damaged.

Stress Test

Some heart problems are easier to diagnose when your heart is working hard and beating fast.

During stress testing, you exercise (or are given medicine if you're unable to exercise) to make your heart work hard and beat fast while heart tests, such as an EKG or echo, are done.