Thus depending on when a-fib occurs helps determine treatment options. During a normal heartbeat, the electrical impulses that cause the atria to contract originate in the sinus node, a small area of the right atrium. During atrial fibrillation, however, these impulses come from all over the atria, triggering 300 to 500 contractions per minute within the heart's upper chambers. The rapid and irregular heartbeat produced by atrial fibrillation cannot pump blood out of the heart efficiently. As a result, blood tends to pool in the heart chambers, increasing the risk of blood clot formation inside the heart.
Blood clots can travel from the heart into the bloodstream and circulate through the body.
Ultimately, they may become lodged in an artery, causing pulmonary embolism, stroke and other disorders. In general, anything that disturbs the normal electrical impulses in the heart can trigger a cardiac arrhythmia, causing the heart to beat too quickly, too slowly, or erratically. In many patients, the underlying cause of atrial fibrillation is more serious than the arrhythmia itself. Some individuals with atrial fibrillation have periods of completely normal heartbeats. For Your doctor will ask about your family history of cardiovascular disorders and will review your personal medical history, including any possible risk factors for atrial fibrillation.