University of Utah researchers have found that delayed-enhancement magnetic resonance imaging (DE-MRI) holds promise for predicting treatment outcomes and measuring disease progression for patients with atrial fibrillation (AF), a little known heart rhythm disorder that affects more than 3.5 million Americans and causes more than 66,000 deaths a year. Their latest study on a novel application of this technology for AF appears in the April 7 issue of the journal Circulation.