Research Activities, August 2013
New review evaluates latest data on rate control and rhythm control strategies for treating atrial fibrillation
Comparative Effectiveness Research
Atrial fibrillation, an irregular and often rapid heart beat that can hamper blood flow to the body, affects more than 2.3 million Americans. Strategies to slow the heart rate to a normal range (rate control) and strategies to revert the heart rhythm back to normal (rhythm control) result in similar outcomes in all-cause mortality, cardiovascular mortality, and stroke in older patients with mild symptoms from atrial fibrillation, according to a new research review by AHRQ’s Effective Health Care Program.
The review finds that rate-control strategies are superior to rhythm-control strategies in reducing hospitalizations from cardiovascular events in these patients. Although there are a limited number of studies that assessed comparable rate-control therapies and outcomes, strong evidence showed the benefit of calcium channel blockers (verapamil or diltiazem) compared with digoxin for ventricular rate control. For comparisons of methods for electrical cardioversion into sinus rhythm, the review found strong evidence that use of a single biphasic waveform is more effective than use of a single monophasic waveform.
There was also strong evidence supporting pulmonary vein isolation versus antiarrhythmic drugs for maintaining sinus rhythm in a select subset of patients (i.e., younger patients with paroxysmal atrial fibrillation and mild structural heart disease). Because of the wide range of options within each strategic treatment approach for atrial fibrillation, additional studies are needed to evaluate the comparative safety and effectiveness of individual antiarrhythmic medications and procedures, especially within specific subgroups of patients that are likely to be encountered in clinical practice (such as those with heart failure).
These findings and others can be found in the research review, Treatment of Atrial Fibrillation, at http://go.usa.gov/jbAH.