Epicardial versus Transvenous Left Ventricular Lead Placement in Patients Receiving Cardiac Resynchronization Therapy: Results from a Randomized Prospective Study - Doll, N.; Piorkowski, C.; Czesla, M.; Kallenbach, M.; Rastan, A. J.; Arya, A.; Mohr, F. W. (The Thoracic and Cardiovascular Surgeon, 2008)