Definition

Tachycardia is a rapid heart rate. It has a rate of more than 100 beats per minute.

It is normal for your heart rate to increase in response to exercise or stress. However, there are several types of abnormal tachycardias. This type is known as arrhythmias. This arrhythmia can start in two different areas of the heart:

• Atria (upper part of the heart)—called supraventricular tachycardias
• Ventricles (the lower part of the heart)—called ventricular tachycardia

This condition can be life threatening. It can be treated. If you think you or someone you know has this condition, call for emergency medical services right away.

Electrical System and Chambers of the Heart

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Causes

Electrical impulses control the action of the heart. These impulses start from a node in the heart or other areas of the heart tissue. Tachycardia is caused by abnormal impulses.

Risk Factors

Factors that may increase your chances of tachycardia:

• Heart disease, especially a prior heart attack
• Cardiomyopathy —damage to the muscle wall of the lower chambers of the heart
• Electrolyte abnormalities—too much or too little calcium, sodium, magnesium, and potassium in the blood
• Myocardial ischemia—insufficient blood flow to heart muscle tissue
• Hypoxemia—not enough oxygen in the blood
• Acidosis—too much acid in the body’s fluids

Symptoms

Tachycardia may cause:

• Heart palpitations
• Fast heart rate
• Lightheadedness
• Fainting or near fainting
• Chest pain
• Shortness of breath

Diagnosis

Your doctor will ask about your symptoms and health history. A physical exam will be done.

Tests may include:

• EKG to test the electrical activity of the heart
• Holter monitor —portable device that measures electrical activity of the heart over 24 to 48 hours
• Exercise test —particularly if the symptoms occur during physical activity
• Electrophysiology study —an invasive test where wires are placed inside the heart to see where the abnormal rhythm starts
• Cardiac catheterization —a tube is inserted into the heart through a vein or artery to check blood flow to the heart

Treatment

Talk with your doctor about the best treatment plan for you. Treatment options include the following:

Implantable Cardioverter Defibrillator (ICD)

An ICD is a device that constantly checks your heart activity. If you have an irregular rhythm, it will shock your heart back to a normal one. The device is placed under your skin during a surgery.

Device to Correct Tachycardia

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Prevention

To help reduce your chances of tachycardia:

• Maintain a healthy weight
• Begin a safe exercise program. Talk to your doctor before starting.
• If you smoke, quit. Talk to your doctor about tools to help you succeed.
• Eat a healthful diet. Keep it low in saturated fat. Aim for food rich in whole grains, fruits, and vegetables.
• Manage stress.
• Avoid or limit caffeine and alcohol.
• Have regular physical exams.
• Treat underlying medical problems, such as or

Treat any underlying medical problems. This is very important with heart related issues like high blood pressure or high cholesterol.