(April 30, 2009 - Insidermedicine) Watch Dr. Jonathan Halperin, MD, the Robert and Harriet Heilbrunn Professor of Medicine at Mount Sinai School of Medicine, discuss what he would do if he had an irregular heartbeat and was diagnosed with atrial fibrillation. Dr. Halperin is also the Director of Clinical Cardiology Services at the Zena and Michael A. Wiener Cardiovascular Institute at the Mount Sinai Medical Center.