Atrial fibrillation is the most common type of arrhythmia in adults, with the prevalence increasing from less than 1 percent in persons younger than 60 years to more than 8 percent in those older than 80 years.1 Each year in the United States, there are more than 700,000 admissions for cardiac dysrhythmias,2 with about one third of these resulting from atrial fibrillation.3 The aging of the U.S. population will make this problem even more prevalent in the day-to-day practice of physicians providing primary care to adults.
In this issue of American Family Physician,4 the clinical practice guideline created by a joint panel of the American Academy of Family Physicians (AAFP) and the American College of Physicians (ACP) in collaboration with the Johns Hopkins Evidence-Based Practice Center is summarized.5 This guideline is one product of the effort of the AAFP to promote evidence-based practice. When the Agency for Health Care Policy and Research (now the Agency for Healthcare Research and Quality) first established the evidence-based practice centers and solicited topics for examination, the AAFP recommended an evidence review of the management of newly detected atrial fibrillation. AAFP members and staff served as consultants to the Johns Hopkins Evidence-Based Practice Center at the time. The Center’s report on atrial fibrillation served as the foundation for the collaborative efforts of the ACP and the AAFP in the production of this guideline. This is the first guideline specifically created by a joint review and synthesis of the literature by these organizations, and it was clear during the process that they share the goal of promoting evidence-based, patient-centered practice. It is hoped that this will be the first of many collaborative efforts.
The evidence reviewed supports a straightforward approach to management for most patients with atrial fibrillation. The central question facing physicians is whether to restore and maintain sinus rhythm, or to control heart rate and prevent stroke. Rhythm control is not superior to the combination of rate control and chronic anticoagulation in reducing morbidity and mortality, and rhythm control may be associated with higher mortality rates in some patient subgroups.
Rate control and prevention of stroke are the mainstays of atrial fibrillation management. Rate control is best accomplished with atenolol, metoprolol, diltiazem, or verapamil. Prevention of stroke requires adjusted-dose warfarin unless the patient has a very low risk of stroke or a specific contraindication to the use of warfarin. As physicians, we tend to consider “soft” contraindications, such as risk of falling. Results from studies using adjusted-dose warfarin clearly show that the benefits generally outweigh the harms, so we must be cautious when avoiding warfarin in the context of relative or theoretical contraindications. We need to balance the theoretical, even unproven, risk of some adverse complication of anticoagulation with the proven benefit of stroke prevention.
This guideline provides an outline for the care of the majority of patients with atrial fibrillation. Care will be straightforward for most of these patients and can be accomplished in the office of the family physician.