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Quick Facts

Premature Beats


The Manual's Editorial Staff

Last full review/revision Jul 2020| Content last modified Jul 2020
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Your heart is a muscle that pumps blood through your body. Your heart rate is how fast your heart beats. Your heart should always have a regular, rhythmic beat, like the ticking of a clock.

Your heart has four chambers. The atria are the two upper chambers. The ventricles are the two lower chambers. The atria pump blood into the ventricles. The ventricles pump blood to your lungs and your body (see also Biology of the Heart Biology of the Heart The heart is a hollow organ made of muscle. The heart and blood vessels are part of your cardiovascular system. Your heart pumps blood through your blood vessels Blood carries oxygen and nutrients... read more ).

Special pacemaker cells in a part of the atria called the SA node (sinoatrial node) send out regular electrical signals to your heart muscle to make it contract.

Your heart's conduction system has tiny strips of tissue sort of like electrical wires. The conduction system carries the pacemaker signals to the rest of your heart. The signals must get to all your heart muscle cells at just the right time so your heart gives a good, strong beat that pumps blood properly.

What are premature beats?

An atrial premature beat is when the early signal comes from your atria. These premature beats are common in many healthy people.

A ventricular premature beat is when the early signal comes from your ventricles. These premature beats are common among older people.

What causes premature beats?

What are the symptoms of premature beats?

Premature beats don't usually cause symptoms.

Some people can feel the extra heartbeats (palpitations). If you have a lot of premature ventricular beats when you exercise, you may feel weak or unable to exert yourself as much as normal.

How can doctors tell if I have premature beats?

Doctors feel your pulse and do:

An ECG is a quick, painless test that measures your heart’s electrical activity using stickers and cables on your chest, arms, and legs.

How do doctors treat premature beats?

Usually no treatment is needed, other than avoiding:

  • Physical or emotional stress

  • Coffee, tea, or alcohol

  • Some cold, allergy, and asthma medicines

If you have many atrial premature beats that are very uncomfortable, doctors may give you medicines to make your heart beat in a normal rhythm.

If you have ventricular premature beats and recently had a heart attack or have heart failure that causes symptoms, doctors may prescribe medicine called beta-blockers.

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