Arrhythmia

A heart arrhythmia is an abnormal heart rhythm that is too fast, too slow, or erratic. Arrhythmias occur when your heart’s conduction—the system of electrical impulses that coordinate your heartbeats—doesn’t work properly.

Arrhythmias can be life-threatening or completely harmless. They’re caused by factors such as heart disease, a heart attack, recent heart surgery, disorders within the heart’s conduction system itself, blood imbalances, too much caffeine, stress, and even sleep problems.

Some heart arrhythmias are so brief that they don’t cause serious problems. But if an arrhythmia occurs over a longer period of time, it can affect the overall rhythm of the heart, causing it to pump blood less effectively and potentially causing damage to vital organs. Serious arrhythmias can lead to stroke and heart failure, and can also cause underlying heart conditions to become worse.

A fast heart rate is called tachycardia and a slow heartbeat is called bradycardia.

Types of arrhythmias

Many types of heart rhythm disorders exist. Here are a few of the most common:

Premature atrial contractions (PACs)—These early extra beats start in one of the atria, the heart’s two upper chambers. They are harmless and don’t usually require treatment.

Premature ventricular contractions (PVCs)—Common and generally benign, a PVC is felt as a skipped heartbeat but is actually an early extra beat that starts in the heart’s two lower chambers, the ventricles.

Atrial fibrillation—A quivering or irregular heartbeat in the upper chambers of the heart that causes blood to move through the ventricles more slowly than normal. Atrial fibrillation can lead to blood clots, stroke, heart failure, and other heart-related complications. It’s the most common serious arrhythmia in people over the age of 65.

Atrial flutter—Similar to atrial fibrillation but usually more organized and regular, atrial flutter happens most often in people who have had surgery for heart disease. It usually changes to atrial fibrillation.

Ventricular fibrillation—When the heart’s lower chambers quiver and can’t contract or pump blood around the body, causing a medical emergency. Ventricular fibrillation must be treated with CPR and defibrillation as soon as possible.

Sick sinus syndrome—A slow or erratic heartbeat that occurs when your sinus node, which is responsible for setting the pace of your heart, doesn’t send impulses normally, causing your heart to not pump enough blood. This condition is sometimes treated with a pacemaker.

Symptoms

Arrhythmias don’t always cause symptoms, and even noticeable symptoms don’t necessarily mean you have a serious problem. But it’s a good idea to seek medical care if you suddenly or frequently experience any of the following symptoms:

  • Palpitations (a feeling of skipped heart beats, fluttering, or flip-flops)
  • Pounding in your chest
  • Dizziness or light-headedness
  • Fainting
  • Shortness of breath
  • Sweating
  • Chest pain or tightness
  • Weakness or fatigue

Treatment

Most arrhythmias are considered harmless and don’t require treatment. But if yours is diagnosed as clinically significant, your doctor will set a treatment plan that might include:

  • Medications.
  • Implantable devices such as a pacemaker or ICD (implantable cardioverter-defibrillator).
  • Non-surgical procedures such as catheter ablation, in which a small amount of heart tissue is painlessly damaged using electrodes at the tip of a catheter. The procedure creates an electrical block along the pathway causing your arrhythmia.
  • In some cases, surgery.