What causes arrhythmia?
The heart has 4 compartments, or chambers. The walls of the heart squeeze together (contract) to push blood through the chambers. The contractions are controlled by an electrical signal that begins in the heart's natural "pacemaker" (called the sinoatrial node). Nerve impulses and hormones in the blood influence the rate of the contractions. A problem in any of these can cause an arrhythmia.
Minor arrhythmias may be caused by excessive alcohol use, smoking, caffeine, stress or exercise. The most common cause of arrhythmias is heart disease, particularly coronary artery disease, abnormal heart valve function and heart failure. However, arrhythmias can occur for no known reason.
Acute Management of Atrial Fibrillation: Part II. Prevention of Thromboembolic Complications by DE King, MD; LM Dickerson, PharmD; JL Sack, MD (American Family Physician July 15, 2002, http://www.aafp.org/afp/20020715/261.html)
Written by familydoctor.org editorial staff