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Heart Disease Health Center

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When Your Heart Rhythm Isn't Normal

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Diagnosis of Arrhythmias

To diagnose an arrhythmia or find its cause, doctors use tests including:

Electrocardiogram -- Also called an EKG or ECG, this test records the electrical activity of your heart. You wear small electrode patches on your chest, arms, and legs for the quick, painless test, which you take in your doctor's office.

Holter monitor -- This is a portable EKG that you'll use for 1 to 2 days. You'll have electrodes taped to your skin. It's painless and you can do everything but shower while wearing the electrodes.

Event monitor -- If your symptoms don't happen often, your doctor may suggest you wear one of these, usually for about a month. This is a device that, when you push a button, will record and store your heart's electrical activity for a few minutes. Each time you notice symptoms, you should try to get a reading on the monitor. Your doctor will interpret the results.

Stress test -- There are different kinds of stress tests. The goal is to check how much stress your heart can manage before having a heart rhythm problem or not getting enough blood flow to the heart. For the most common type of stress test, you'll walk on a treadmill or pedal a stationary bike at increasing levels of difficulty while you're getting an EKG and getting your heart rate and blood pressure monitored.

Echocardiogram-- This test uses ultrasound to evaluate heart muscle and heart valves.

Cardiac catheterization-- Your doctor will insert a long, thin tube, called a catheter, into a blood vessel in your arm or leg. She will guide it to your heart with help from a special X-ray machine. Then she'll inject dye through the catheter to help make X-ray videos of your heart's valves, coronary arteries, and chambers.

Electrophysiology study -- This test records your heart's electrical activities and pathways. It can help find out what's causing heart rhythm problems and find the best treatment for you. During the test, your doctor will safely reproduce your abnormal heart rhythm and then may give you different medications to see which controls it best, or to see what procedure or device you need to treat it.

Head-up tilt table test -- Doctors use this test to find out what's causing fainting spells. It measures the difference in heart rate and blood pressure when you're standing up or lying down. You'll get this test in a lab. You'll lie on a stretcher, tilted at different angles while you're getting an EKG and specialists are checking your blood pressure and oxygen level.

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