Drug therapies and atrial fibrillation

Cardiology Review® Online, November 2007, Volume 24, Issue 11

The increasing importance of cardiac imaging in cardiology practice has been reflected over the past year with increased coverage in the pages of this journal. This issue continues that emphasis, offering a combined cardiac imaging and coronary artery disease (CAD) section report that is concerned with magnetic resonance (MR) imaging. Dr Cosima Jahnke and associates from Germany studied 513 patients with known or suggested CAD using combined adenosine and dobutamine stress MR perfusion imaging. They found that these procedures identified patients at high risk for subsequent cardiac events; conversely a normal test predicted a 3-year event-free survival in excess of 99%!Dr Tasneem Naqvi (our "Images in Cardiology" section editor) comments on the clinical role of MR stress tests. Another paper looking at combined topical areas (in the arrhythmia and hypertension sections) is from the Netherlands and features Dr Michiel Rienstra as lead author. Using RACE study data, the researchers found that rhythm control (drug treatment) of atrial fibrillation in hypertensive patients led to increased cardiovascular morbidity and mortality. They advocate consideration of a rate control strategy instead, and Dr Joseph Dell'Orfano describes the pros and cons of this approach in his commentary. In the arrhythmia section, Dr Robert J. Anderson uses another large database (that of the National Ambulatory Medical Care Survey) to track trends in the use of anticoagulation for atrial fibrillation between 1994 and 2003. His conclusions—commented upon by Dr Ernst Raeder—are several, not the least of which are the underuse of anticoagulation in high-risk groups and possible overuse in low-risk patients! Coronary artery disease is also represented in the article by Dr Kenneth W. Mahaffeydetailing the rise in creatine kinase-myocardial band (CK-MB) after coronary artery bypass surgery. Dr Mahaffey's patient population included 4401 patients with non—ST-segment elevation acute coronary syndromes. As the cardiac enzyme level increased, so did mortality. Dr Harold Lazar, our cardiac surgical consultant, points out several important caveats to the study and questions whether CK-MB levels need be obtained routinely in all cardiac surgical patients.

—Peter F. Cohn