Causes of Arrhythmias (Heart Rhythm Disturbances)

Arrhythmias are very common, both the harmless type and the dangerous type. An arrhythmia can be caused by:

The heart's natural pacemaker developing an abnormal rate or rhythm
The normal electrical conduction pathway being interrupted
Another part of the heart (other than the sinus node) taking over as pacemaker

The most common cause of dangerous arrhythmias is a heart attack. When the heart is deprived of adequate blood supply during a heart attack, its electrical activity can become erratic. Diseased heart valves and diseased heart muscle, direct injury to the heart, diseases that alter the body's chemical balance, and several kinds of medication can also upset the heart's circuitry.

The most common causes of arrhythmia include:

]]>Coronary artery disease]]> (eg, heart attacks)
Diseased myocardium (heart muscle)
Abnormal heart valves
Birth defects
Stress
Caffeine
Tobacco
Alcohol
Illegal stimulants, such as cocaine and methedrine
Diet pills
Some over-the-counter medications, such as cough and ]]>cold]]> medicines
Various prescription medications, for example:
- Heart medicines
- ]]>Asthma]]> medicines
- Psychoactive medicines, such as antidepressants
- Thyroid hormone replacement medicines

References:

Harrison's Principles of Internal Medicine . 14th edition. McGraw-Hill; 1998.

Mayo Clinic and Foundation for Medical Education and Research website. Available at: http://www.mayo.edu/ .

National Heart, Lung, and Blood Institute website. Available at: http://www.nhlbi.nih.gov/ .

National Institutes of Health website. Available at: http://www.nih.gov/ .

Snow, V, Weiss, KB, LeFevre, M, et al. Management of newly detected atrial fibrillation: a clinical practice guideline from the American Academy of Family Physicians and the American College of Physicians. Ann Intern Med. 2003;139:1009

Weber, BE, Kapoor, WN. Evaluation and outcomes of patients with palpitations. Am J Med. 1996;100:138.

Last reviewed June 2008 by ]]>Michael J. Fucci, DO]]>

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.