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    How Atrial Fibrillation Is Diagnosed

    An irregular heartbeat may or may not cause symptoms. So if your doctor suspects you have atrial fibrillation (AFib), he may ask for tests to confirm the diagnosis, find out what's causing it, and figure out the best way to treat it.

    Doctor Exam

    Sometimes your primary care or family doctor will be the one who diagnoses AFib. But in many cases, you see a heart doctor, called a cardiologist. Cardiologists who specialize in irregular heartbeats are called electrophysiologists.

    First, the doctor will ask detailed questions about your symptoms, health habits, and health problems you or another family member have had.

    During the physical exam, he's likely to:

    • Listen to your heartbeat's rate and rhythm
    • Take your pulse and blood pressure
    • Listen to your lungs
    • Check for signs of heart muscle or valve problems

    Electrocardiogram (EKG)

    This simple, painless test is the most helpful. It records your heart's electrical activity. It can show the:

    • Speed of your heartbeat
    • Rhythm of your heartbeat
    • Strength and timing of electrical signals passing through your heart

    A doctor or technician places small patches, called electrodes, on different areas of your body, including several on your chest. These pick up signals that make wave patterns on the EKG results. It gives your doctor a picture of your heart's overall electrical activity.

    But because the test is a quick snapshot, a standard EKG won't always catch AFib. Sometimes you'll need a portable EKG machine to keep tabs on your heart over a longer time.

    Holter monitor. You keep this with you for 24 to 48 hours while it continuously records your heart's electrical activity. The extra time gives a better chance of picking up an abnormal heart rhythm, what doctors call an arrhythmia.

    Just as with a regular EKG, you'll have small electrodes attached to your chest. Wires connect these electrodes to a small recorder you can clip on a belt, keep in a pocket, or hang around your neck.

    Then you just go about doing what you usually do. Your doctor will check the recorded results later.

    Event monitor. This works like a Holter monitor, but it only records your heart's activity at certain times. It might automatically start recording when it senses something is off. Or you might have to push a button when you feel:

    • Dizzy
    • Weak
    • Lightheaded
    • A racing or fluttering heart

    You may need to wear it for a couple of months -- as long as it takes to catch and record the trouble.

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