Focus on atrial fibrillation recognises growing importance of common arrhythmia

When we're young, a racing heart often means love is in the air. If you're a 'baby boomer,' it might mean you've just joined the 2.2 million Americans who have atrial fibrillation (AF), an irregularity in the heart's rhythm that grows more common as we age and markedly increases the risk for stroke.

'We're seeing more and more patients with atrial fibrillation,' said N.A. Mark Estes III, M.D., F.A.C.C., a professor of medicine at Tufts University School of Medicine and director of the New England Cardiac Arrhythmia Centre at Tufts-New England Medical Centre, Boston. 'The good news is that we have practical and useful tools to use in assessing patient risk and good evidence on how to treat this condition.'

Atrial fibrillation occurs when the upper chambers of the heart - the atria - quiver in an uncoordinated way rather than contracting with a steady tempo. Not only can this result in a rapid, irregular heart beat, but blood can pool in the atria and form clots that travel to the brain, causing a stroke. Some 3 percent to 4 percent of people over age 60 have atrial fibrillation, a risk that climbs to more than 5 percent after age 70.

The 26 February 2008 edition of the Journal of the American College of Cardiology (JACC) places a spotlight on atrial fibrillation, with a special focus issue featuring review articles, editorials, and original research on the diagnosis and management of this common arrhythmia. One research study, for example, raises the intriguing possibility that statins - medications that are widely prescribed for lowering cholesterol levels and reducing the risk of heart attack and stroke - may also reduce the risk of atrial fibrillation.

For the study, researchers from France analysed data from six randomised controlled trials involving nearly 3,600 patients, all of whom either had experienced atrial fibrillation in the past or had a high risk of developing new atrial fibrillation following a heart attack or coronary bypass surgery. The researchers found that patients who were taking statins were 61 percent less likely to develop atrial fibrillation than were patients not taking these medications.

Laurent Fauchier, M.D., Ph.D., who led the study, said it is too early to consider prescribing statins to all patients with a history of atrial fibrillation, but the results of the analysis suggest statins may offer an intriguing bonus.

'A positive effect of statins on atrial fibrillation may contribute to a reduction in the number of strokes or episodes of worsening heart failure,' said Dr Fauchier, a professor of cardiology at Centre Hospitalier Universitaire Trousseau, Tours, France. 'What patients should know is this: If your doctor prescribes a statin for any reason, it will decrease the risk of cardiac events related to atherosclerosis, and by the way, it may also decrease the risk of atrial fibrillation.'

Also included in the special focus issue of JACC is a set of performance measures jointly developed by the American College of Cardiology and the American Heart Association, in collaboration with the Heart Rhythm Society. The performance measures can be used by physicians and health systems to monitor the quality of care delivered to patients with atrial fibrillation. They focus on three key steps for the prevention of stroke: 1. Use of a simple point system to identify patients at high risk for stroke; 2. Prescription of blood thinning medications, particularly warfarin (Coumadin), to reduce the risk of stroke; and 3. Monitoring of the effects of warfarin at least monthly.

'There is clear evidence that warfarin reduces the risk of stroke,' said Dr Estes, who chaired the performance measures writing committee. 'We've tried to develop a practical and useful tool that physicians can use right from the beginning, when a patient first comes to the office with atrial fibrillation.'