How you prepare

Before your doctor decides if you need a pacemaker, you'll have several tests done to find the cause of your irregular heartbeat. Tests done before you get a pacemaker could include:

• Electrocardiogram (ECG or EKG). This quick and painless test measures the electrical activity of the heart. Sticky patches (electrodes) are placed on the chest and sometimes the arms and legs. Wires connect the electrodes to a computer, which displays the test results. An ECG can show if the heart is beating too fast, too slow or not at all.
• Holter monitoring. A Holter monitor is a small, wearable device that keeps track of the heart's rhythm. Your doctor may want you to wear a Holter monitor for 1 to 2 days. During that time, the device records all of your heartbeats. Holter monitoring is especially useful in diagnosing heartbeat problems that occur at unpredictable times. Some personal devices, such as smartwatches, offer electrocardiogram monitoring. Ask your doctor if this is an option for you.
• Echocardiogram. This noninvasive test uses sound waves to produce images of the heart's size, structure and motion.
• Stress test. Some heart problems occur only during exercise. For a stress test, an electrocardiogram is taken before and immediately after walking on a treadmill or riding a stationary bike. Sometimes, a stress test is done along with echocardiography or nuclear imaging.