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Problems with the rhythm of your heart

  • Arrhythmia or dysrhythmia

    Arrhythmia or dysrhythmia is an irregular heartbeat or rhythm. There are many kinds. Some of the most common are:

    • when your heart has extra beats
    • when your heart beats too fast
    • when your heart beats too slowly

    When your heart has extra beats

    You may have one of the following problems if has extra beats.

    • Premature atrial contraction: Early heartbeats start from the upper chambers of the heart. Usually, no medicine treatment is needed.
    • Premature ventricular contraction: If the ventricles (bottom chambers) of your heart contract before the atria (top chambers) contract, you have a premature ventricular contraction, (or PVC). If you have a history of heart disease, or if you have frequent PVCs, your health care team needs to know. Often there are no symptoms. Occasionally, symptoms may include:
      • palpitations
      • weakness
      • shortness of breath
      • chest pain.

    You may need treatment or observation. Often, no treatment is needed.

    When your heart beats too fast

    Did you know?

    Atrial fibrillation can cause heart failure.

    You may have one of the following problems if your heart is beating too fast.

    • Sinus tachycardia: Sinus tachycardia occurs when your heart speeds up when you are exercising, being active, feeling anxious or afraid and when you have a fever. This is normal. If your heart rate stays at this fast rate for a long period of time, you may feel pounding in your chest (palpitations), lightheadedness, weakness, shortness of breath or other symptoms. (It is normal for your heart to speed up when you exercise and slow down when you are at rest.)
    • Atrial fibrillation: Atrial fibrillation occurs when electrical impulses travel through the atria (top part of your heart) in a random or disorganized way. This causes the atria to beat (or contract) many times for each one time that the ventricles contract. When your atria are fibrillating, they are not able to pump blood effectively. If you have atrial fibrillation, your risk of stroke is up to five times greater than people who have a normal rhythm. Your doctor will recommend medicine to decrease your risks and regulate your heart rhythm. Sometimes atrial fibrillation occurs in healthy people, but usually it happens if you also have high blood pressure, a history of valve or heart disease, coronary artery disease or hyperthyroidism.
    • Ventricular tachycardia: Ventricular tachycardia (V-tach) occurs when you have consecutive episodes of premature (early) ventricular contractions. Some people tolerate this, while others may faint. This condition can be life-threatening. An electrophysiology study can tell your doctor if you have this rhythm, or one that looks similar. Sometimes, it is found on an ECG (electrocardiogram) or portable monitor.
    • Ventricular fibrillation: Ventricular fibrillation occurs when electrical impulses in your heart travel through the ventricles (bottom chambers of your heart) in a disorganized way. This prevents your ventricles from contracting correctly. When the ventricles are fibrillating, they are not able to pump blood to your body. You will pass out or lose consciousness. An electrical shock or defibrillation can put your heart back into a normal rhythm.


    Ventricular fibrillation is a life-threatening problem.

    When your heart beats too slowly

    You may have one of the following problems if your heart is beating too slowly.

    • Sinus bradycardia: Bradycardia occurs when your heart beats slower than normal - fewer than 60 beats a minute. A normal sinus rhythm (or heart rate) is 60 to 100 beats per minute. A slow heart rate may be caused by medicines and is not a problem, unless it causes symptoms such as fatigue, shortness of breath, or lightheadedness. Your doctor may recommend a temporary or permanent pacemaker and may change your medicine if your heart rate is too slow.
    • Heart block: Heart block is the blocking of electrical impulses through the heart. Some heart blocks do not need to be treated. It becomes serious when your heart beats too slowly to maintain good circulation. Heart block is caused by certain medicines, disease or wear on the electrical conduction path. Heart block may cause your heart to beat out of rhythm. If it worsens into complete heart block, impulses from the heart's atria don't reach the ventricle. The ventricles beat independently at a very slow rate. You'll become weak, dizzy or lightheaded. If you have complete heart block, you will need a permanent pacemaker.

    Did you know?

    A slow heart rate does not necessarily mean you have an abnormal heart.