Atrial fibrillation is a condition that results in irregularity of the heartbeat, due to the loss of coordinated electrical activity in the upper chambers of the heart. Atrial fibrillation is one of the most common irregularities of the heartbeat. It affects patients of all ages, although it is far more common in older segments of the population.
Under normal circumstances, the heartbeat originates in the top right-hand chamber of the heart. Called the right atrium, this portion of the heart functions to receive blood from the body and push it into the large pumping chamber, called the ventricle, on the bottom of the heart. The timing and contraction of the heartbeat depends on this atrial regulation. When it is lost, the atria develop a chaotic electrical activity that results in a very rapid, irregular pulse. This chaotic electrical activity is called fibrillation. This should not be confused with the catastrophic fibrillation, called ventricular fibrillation, that may occur in the pumping chambers on the bottom of the heart.
Many things may cause atrial fibrillation. The more common reasons include aging, with degeneration of the electrical system of the heart; thyroid diseases; heart attack; and caffeine or other medications that may cause irregularity of the heartbeat. Disease of the valves of the heart, particularly leaking of the heart valves that connect the top chambers to the bottom chambers of the heart, is another cause of atrial fibrillation.
Signs and symptoms of atrial fibrillation include weakness, dizziness, shortness of breath, and a rapid, irregular pulse. Some patients may also experience chest pain. Interestingly, some patients seem to have no symptoms at all.
The treatment of atrial fibrillation is directed in two areas. The first is to reduce the symptoms caused by the rapid, irregular heartbeat. This can be addressed by slowing the pulse, and reducing the risk of stroke, by using anticoagulant medicine such as warfarin. Secondly, conversion of the heart rhythm to the normal sinus rhythm is attempted using medicine and, sometimes, an electrical shock called cardioversion. It is also necessary to look for and correct any underlying cause for the atrial fibrillation.