Luke’s-Roosevelt Hospital Center in New York City. Dr. Klein balances providing expert patient care and resident education while working in the Department of Medicine. He is certified to practice internal medicine and cardiovascular disease by the American Board of Internal Medicine, and he is certified to practice nuclear cardiology, as well as certified by the National Board of Echocardiography. Dr. Klein is fluent in English and Hebrew, and he is dedicated to his patients and his students, and approaches every obstacle with care and patience.