Normally, your heart works as a pump that brings blood to the lungs and the rest of the body.
To help this happen, your heart has an electrical system that makes sure it contracts (squeezes) in an orderly way.
The electrical impulse that signals your heart to contract begins in the sinoatrial node (also called the sinus node or SA node). This is your heart's natural pacemaker.
The signal leaves the SA node and travels through the heart along a set electrical pathway.
Different nerve messages signal your heart to beat slower or faster.
When you have an arrhythmia, your heartbeat may be:
Too slow (bradycardia)
Too quick (tachycardia)
Irregular, uneven, or skipping beats
An arrhythmia may be present all of the time or it may come and go. You may or may not feel symptoms when the arrhythmia is present. Or, you may only notice symptoms when you are more active.
Symptoms can be very mild, or they may be severe or even life-threatening.
Common symptoms that may occur when the arrhythmia is present include:
A special test, called an electrophysiology study (EPS), is done to take a closer look at the heart's electrical system.
Treatment
When an arrhythmia is serious, you may need urgent treatment to restore a normal rhythm. This may include:
Electrical "shock" therapy (defibrillation or cardioversion)
Implanting a short-term heart pacemaker
Medications given through a vein (intravenous) or by mouth
Sometimes, getting better treatment for your angina or heart failure will decrease the chance of having an arrhythmia.
Medications called anti-arrhythmic drugs may be used:
To prevent an arrhythmia from happening again
To keep your heart rate from becoming too fast or too slow
Some of these medicines can have side effects. Take them as prescribed by your health care provider. Do not stop taking the medicine or change the dose without first talking to your health care provider.
Other treatments to prevent or treat abnormal heart rhythms include:
Cardiac ablation used to destroy areas in your heart that may be causing your heart rhythm problems
Pacemaker, a device that senses when your heart is beating irregularly, too slowly, or too fast. It sends a signal to your heart that makes your heart beat at the correct pace.
Expectations (prognosis)
The outcome depends on several factors:
The kind of arrhythmia -- some arrhythmias may be life threatening if not treated right away, or do not respond well to treatment
Epstein AE, DiMarco JP, Ellenbogen KA, Estes NA 3rd, Freedman RA, Gettes LS, et al. ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices): developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons. Circulation. 2008;117:e350-e408.
Olgin SE. Approach to the patient with suspected arrhythmia. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 62.
Rubart M, Zipes DP. Genesis of cardiac arrhythmias, electrophysiologic considerations. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 9th ed. Philadelphia, Pa: Saunders Elsevier;2011:chap 35.
Review Date:
6/22/2012
Reviewed By:
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Michael A. Chen, MD, PhD, Assistant Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical Center, Seattle, Washington. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.
