Arrhythmias may not cause any signs or symptoms. In fact, your doctor might find you have an arrhythmia before you do, during a routine examination. Noticeable signs and symptoms don't necessarily mean you have a serious problem, however.

Noticeable arrhythmia symptoms may include:

  • A fluttering in your chest
  • A racing heartbeat (tachycardia)
  • A slow heartbeat (bradycardia)
  • Chest pain
  • Shortness of breath
  • Lightheadedness
  • Dizziness
  • Fainting (syncope) or near fainting

When to see a doctor

Arrhythmias may cause you to feel premature or extra heartbeats, or you may feel that your heart is racing or beating too slowly. Other signs and symptoms may be related to your heart not pumping effectively due to the fast or slow heartbeat. These include shortness of breath or wheezing, weakness, dizziness, lightheadedness, fainting or near fainting, and chest pain or discomfort. Seek urgent medical care if you suddenly or frequently experience any of these signs and symptoms at a time when you wouldn't expect to feel them.

Ventricular fibrillation is one type of arrhythmia that can be deadly. It occurs when the heart beats with rapid, erratic electrical impulses. This causes pumping chambers in your heart (the ventricles) to quiver uselessly instead of pumping blood. Without an effective heartbeat, blood pressure plummets, cutting off blood supply to your vital organs. A person with ventricular fibrillation will collapse within seconds and soon won't be breathing or have a pulse. If this occurs, follow these steps:

  • Call 911 or the emergency number in your area.
  • If there's no one nearby trained in cardiopulmonary resuscitation (CPR), provide hands-only CPR. That means uninterrupted chest compressions of about 100 a minute until paramedics arrive. To do chest compressions, push hard and fast in the center of the chest. You don't need to do rescue breathing.
  • If you or someone nearby knows CPR, begin providing it if it's needed. CPR can help maintain blood flow to the organs until an electrical shock (defibrillation) can be given.
  • Find out if an automated external defibrillator (AED) is available nearby. These portable defibrillators, which can deliver an electric shock that may restart heartbeats, are available in an increasing number of places, such as in airplanes, police cars and shopping malls. They can even be purchased for your home. No training is required. The AED will tell you what to do. They're programmed to allow a shock only when appropriate.
Jul. 31, 2014

You Are ... The Campaign for Mayo Clinic

Mayo Clinic is a not-for-profit organization. Make a difference today.