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When Your Heart Rhythm Isn't Normal


Causes and Types continued...

Ventricular tachycardia (V-tach). A rapid heart rhythm starting from the heart's lower chambers. Because the heart is beating too fast, it can't fill up with enough blood. This can be a serious arrhythmia -- especially in people with heart disease -- and it may be linked to other symptoms. 

Ventricular fibrillation. This happens when the heart's lower chambers quiver and can't contract or pump blood to the body. This is a medical emergency that must be treated with CPR and defibrillation as soon as possible.

Long QT syndrome. This causes potentially dangerous arrhythmias and sudden death. Doctors can treat it with medications or devices called defibrillators.

Bradyarrhythmias. These are slow heart rhythms, which may be due to disease in the heart's electrical system. If you experience this, call your doctor.

Sinus node dysfunction. This slow heart rhythm is due to a problem with the heart's sinus node. Some people with this type of arrhythmia need a pacemaker.

Heart block. There is a delay or a complete block of the electrical impulse as it travels from the heart's sinus node to its lower chambers. The heart may beat irregularly and, often, more slowly. In serious cases, you'd get a pacemaker.

What Are the Symptoms of Arrhythmias?

An arrhythmia can be silent, meaning you don't notice any symptoms. A doctor can find an irregular heartbeat during a physical exam by taking your pulse or through an electrocardiogram (ECG or EKG).

If you do have symptoms, they may include:

  • Palpitations (a feeling of skipped heart beats, fluttering or "flip-flops")
  • Pounding in your chest
  • Dizziness or feeling light-headed
  • Fainting
  • Shortness of breath
  • Chest pain or tightness
  • Weakness or fatigue (feeling very tired)


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 you're 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.

WebMD Medical Reference

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