1. From the Cardiovascular Center, Seoul National University Hospital (Y.K., D.K., H.K., J.P., Kyung-Hwan Kim, Ki-Bong Kim, D.S., H.A., B.O., Y.P.); and Departments of Internal Medicine (Y.K., D.K., H.K., J.P., D.S., B.O., Y.P.), Thoracic Surgery (Kyung-Hwan Kim, H.A.), and Medicine (S.H.), Seoul National University College of Medicine, Seoul, Korea.