What is tachycardia?

Tachycardia is a resting heart rate that stays above 100 beats per minute when you are resting. The normal adult heart rate ranges from about 50 to 100 beats per minute.

What is the cause?

An electrical signal in your heart starts each heartbeat, causing the heart muscle to squeeze (contract). Normally, this signal starts in the upper right chamber of the heart (the right atrium) at a place called the sinus node. The signal then follows pathways to the upper left atrium and to the lower chambers of the heart (the ventricles).

Many different things can cause a fast resting heart rate. Some of the conditions that can cause your heart to beat faster are:

• Anemia
• High blood pressure
• Pregnancy
• Fever
• Stress
• Thyroid problems

Problems with the heart can cause a fast heart rate. For example:

• Changes in the electrical signal that causes your heart to beat can make your heart beat faster.
• Muscles in the upper chambers of the heart may tend to quiver and send random signals to the lower chambers of the heart.
• The heartbeat may start in the lower chambers of the heart rather than the upper chamber.

What are the symptoms?

The main symptom is feeling your heart beating fast. Other symptoms may include:

• Lightheadedness or fainting
• Nausea
• Cold sweat
• Shortness of breath
• Chest pain
• Weakness

Contact your healthcare provider if you have any of these symptoms in addition to a fast heartbeat.

How is it diagnosed?

Your healthcare provider will ask about your symptoms and medical history and examine you. Tests may include:

• Blood tests
• Chest X-rays
• An ECG (also called an EKG or electrocardiogram), which measures and records your heartbeat. You may have an ECG while you are resting or while you exercise on a treadmill. You may also be asked to wear a small portable ECG monitor for a few days or longer.
• An electrophysiology study, which uses tiny wires put into your heart through your veins to look at the electrical paths in your heart

How is it treated?

The treatment depends on the type of tachycardia that you have. Treatment may include:

• Medicine to slow your heartbeat
• Ablation, which uses a small tube called a catheter to deliver electrical pulses to the inside of the heart. The electrical pulses make small scars that block abnormal electrical pathways. This helps you have a regular heart rhythm.
• An implantable cardiac defibrillator (ICD), which is a device that can shock the heart back to a regular rhythm. In cases of life-threatening heart rhythm problems, ICDs can provide an instant, life-saving electrical shock before medical help arrives.

You may also receive treatment for any health problems you have that may be causing tachycardia.

How can I take care of myself?

If you have heart disease, high blood pressure, or another medical problem, follow your treatment plan. Be sure to take all medicines as prescribed by your provider.

Try to have a heart-healthy lifestyle:

• Eat a healthy diet.
• Try to keep a healthy weight. If you are overweight, lose weight.
• Stay fit with the right kind of exercise for you.
• Learn ways to manage stress.
• If you smoke, try to quit. Talk to your healthcare provider about ways to quit smoking.
• If you want to drink alcohol, ask your healthcare provider how much is safe for you to drink.
• Try to get at least 7 to 9 hours of sleep each night.

Ask your provider:

• How and when you will hear your test results
• How long it will take to recover
• What activities you should avoid and when you can return to your normal activities
• How to take care of yourself at home
• What symptoms or problems you should watch for and what to do if you have them

Make sure you know when you should come back for a checkup.

How can I help prevent tachycardia?

There is no specific way to prevent tachycardia, but a healthy lifestyle can help prevent heart disease, which can cause tachycardia.