Guidelines on atrial fibrillation recommend new approach

Aug 2 2006

Risk factors for stroke should be used to determine whether anti-clotting therapy is given to people with an irregular heartbeat called atrial fibrillation (AF), according to revised Guidelines for the Management of Patients with Atrial Fibrillation released by the American College of Cardiology, American Heart Association and the European Society of Cardiology.

Atrial fibrillation (AF) is the most common heart rhythm disturbance and it increases the risk for stroke, heart failure and all causes of death, especially in women. Presently AF affects more than 2 million Americans and 4.5 million Europeans, according to the joint statement. The number of patients with atrial fibrillation is expected to increase even more due to an aging population, a rising number of people with chronic heart disease and improved diagnostic possibilities.

During AF, the heart's two upper chambers (the atria) quiver instead of beating effectively. Blood isn't pumped completely out of them, so it may pool and clot. If a piece of a blood clot in the atria leaves the heart and lodges in an artery in the brain, a stroke results. Moreover, when the very rapid electrical signals from the atria reach the lower chambers of the heart (the ventricles) they start to beat quickly and irregularly causing palpitations and decreased blood pumping leading to tiredness and breathlessness.

Previous guidelines published in 2001 recommended using several patient characteristics - age, gender, heart disease risk and concurrent conditions - to decide proper anti-clotting therapy for these patients. The new approach recommends that the risk for stroke should be the main factor, said Valentin Fuster, M.D., Ph.D., co-chair of the guidelines writing committee, fellow of all three associations, and professor of medicine and director of the Mount Sinai Cardiovascular Institute in New York.

"We focused on stroke risk because AF is associated with increased long-term risk for stroke," he said. "About 15 percent to 20 percent of strokes occur in people with AF, and those strokes are especially large and disabling.

"Incorporating existing recommendations on anti-clotting therapy from the stroke primary prevention guidelines will streamline patient care and make recommendations clearer for physicians," he said.

In the United States and Europe, hospital admissions for AF have increased by 66 percent during the last 20 years. It is also expensive, with total costs approaching.