Heart Surgery: Aortic Root Enlargement with Valve Replacement. Sequoia Hospital cardiac surgeon Vincent Gaudiani, MD presents an innovative surgical technique that virtually eliminates several of the problems with modern techniques of valvular replacement, such as patient-prosthesis mismatch (or PPM). This is a highly publicized problem that this procedure all but eliminates. Dr. Gaudiani is a senior cardiac surgeon having performed approximately 7000 cardiac operations and has focused his interest on the more difficult and complex problems of operable heart disease in adults. See Dr. Gaudiani perform this innovative technique at 4:30 pm ET / 1:30 PM PT (21:30 UTC).