Change in Heartbeat

Your heart normally beats in a regular rhythm and rate that is just right for the work your body is doing at any moment. The usual resting heart rate for adults is between 50 to 100 beats per minute. Children have naturally higher normal heart rates than adults.

The Reference heart Opens New Window Reference Opens New Window is a pump made up of Reference four chambers Opens New Window Reference Opens New Window: two upper chambers (atria) and two lower chambers (ventricles). It is powered by an Reference electrical system Opens New Window Reference Opens New Window that puts out pulses in a regular rhythm. These pulses keep the heart pumping and keep blood flowing to the lungs and body.

When the heart beats Reference too fast, too slow, or with a skipping (irregular) rhythm, a person is said to have an Reference arrhythmia Opens New Window. A change in the heart's rhythm may feel like an extra-strong heartbeat (Reference palpitation Opens New Window) or a fluttering in your chest. Reference Premature ventricular contractions (PVCs) often cause this feeling.

A heartbeat that is occasionally irregular usually is not a concern if it does not cause other symptoms, such as dizziness, Reference lightheadedness Opens New Window, or shortness of breath. It is not uncommon for children to have extra heartbeats. In healthy children, an extra heartbeat is not a cause for concern.

When heart rate or rhythm changes are minor

Many changes in heart rate or rhythm are minor and do not require medical treatment if you do not have other symptoms or a history of heart disease. Smoking, drinking alcohol or caffeine, or taking other stimulants such as diet pills or cough and cold medicines may cause your heart to beat faster or skip a beat. Your heart rate or rhythm can change when you are under stress or having pain. Your heart may beat faster when you have an illness or a fever. Hard physical exercise usually increases your heart rate, which can sometimes cause changes in your heart rhythm.

Dietary supplements, such as goldenseal, oleander, motherwort, or ephedra (also called ma huang), may cause irregular heartbeats.

It is not uncommon for pregnant women to have minor heart rate or rhythm changes. These changes usually are not a cause for concern for women who do not have a history of heart disease.

Well-trained athletes usually have slow heart rates with occasional pauses in the normal rhythm. Evaluation is usually not needed unless other symptoms are present, such as lightheadedness or fainting (Reference syncope Opens New Window), or there is a family history of heart problems.

When heart rate or rhythm changes are more serious

Irregular heartbeats change the amount of blood that flows to the lungs and other parts of the body. The amount of blood that the heart pumps may be decreased when the heart pumps too slow or too fast.

Changes such as Reference atrial fibrillation Opens New Window that start in the upper chambers of the heart can be serious, because they increase your risk of forming blood clots in your heart. This in turn can increase your risk for having a stroke or a blood clot in your lungs (Reference pulmonary embolism Opens New Window). People who have Reference heart disease Opens New Window, Reference heart failure Opens New Window, or a history of heart attack should be more concerned with any changes in their usual heart rhythm or rate.

Fast heart rhythms that begin in the lower chambers of the heart are called ventricular arrhythmias. They usually are fast and regular, such as ventricular tachycardia, or fast and irregular, such as ventricular fibrillation. These types of heart rhythms make it hard for the heart to pump enough blood to the brain or the rest of the body and can be life-threatening. Ventricular arrhythmias may be caused by heart disease such as heart valve problems, impaired blood flow to the heart muscle (ischemia or a heart attack), a weakened heart muscle (cardiomyopathy), or heart failure.

Ventricular tachycardia is a life-threatening arrhythmia that can quickly lead to ventricular fibrillation, which causes death if not treated. Both usually cause fainting (syncope) within seconds, and you may have Reference symptoms of a heart attack Opens New Window. Emergency medical treatment is needed, such as medicines and electrical shock (defibrillation).

When you have a change in your heart rhythm or rate, you also may have other symptoms, such as chest pain, shortness of breath, lightheadedness, fainting, confusion, or weakness. Changes in your heart rate or rhythm with other symptoms can be caused by a serious heart problem.

Taking illegal drugs (such as stimulants, like cocaine or methamphetamine) or misusing prescription and nonprescription Reference medicines can cause serious heart rhythm or rate changes and may be life-threatening.

The U.S. Food and Drug Administration (FDA) has banned the sale of ephedra, a stimulant sold for weight loss and sports performance, because of concerns about safety. Ephedra has been linked to Reference heart attacks Opens New Window, Reference strokes Opens New Window, and some sudden deaths.

Reference Check your symptoms to decide if and when you should see a doctor.

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This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Reference Terms of Use. Reference How this information was developed to help you make better health decisions.