Griffin, J., Bradley; Miller, Edwin, V.; Hiratzka, Loren, F.; Miller, Edwin, V., Department of Surgery, Division of Thoracic-Cardiovascular Surgery, The University of Iowa Hospitals and Clinics, University of Iowa Medical School, Iowa City, Iowa.; Hiratzka, Loren, F., Department of Surgery, Division of Thoracic Cardiovascular Surgery, The University of Iowa Hospitals and Clinics, University of Iowa Medical School, Iowa City, Iowa; 2139 Auburn Ave., Cincinnati, OH 45219.