Long-Term Echocardiographic Doppler Monitoring of Hancock Bioprostheses in the Mitral Valve Position Paola Melacini, MD, Carla Villanova, MD, Gaetano Thiene, MD, Marco Minarini, BS, Giuseppe Fasoli, MD, Uberto Bortolotti, MD, Giuseppe Ramuscello, MD, Roldano Scognamiglio, MD, Andrea Ponchia, MD, and Sergio Dalla Volta, MD Echocardiographic and Doppler studies were per- formed in 134 patients with a Hancock biopros- thesis in the mitral valve position during a follow- up period of 1 to 216 months. Among the xeno- grafts, 57% were clinically normal and 43% had severe dysfunction. Among the normal Mopros- theses, 35% had echocardiographically thickened mitral cusps (23 mm) withnormal hemodynamic function; by setting the lower 95% confidence lim- it of valve area at 1.7 cm* these patients had a significantly (p <O.Ol) smaller valve area than that of normal control subjects. Evaluation of all thickened normal mitral valves showed the highest incidence of thickening at 9 years after implanta- tion. Valve replacement surgery was subsequently performed in 33 patients with dysfunctioning bio- prostheses, and echocardiographic diagnosis was confirmed in 91% of explanted valves (biopros- thetic stenosis 21%, incompetence 46%, and com- bined stenosis and regurgitation 33%). In 2 vaives that were found to be stenotic on echocardio- graphic examination, a calcium-related commis- sural tear was also observed at reoperatiin, and in another, a paravafvular leak was found. Dystro- phic calcification, isolated (64%) or occasionally associated with fibrous tissue overgrowth (21%), was the main cause of failure. Pannus was present in prostheses with longer satisfactory function (168 f 31 VI 124 f 21 months; p <O.OOl). Long- term performance was evalwted by the Kaplan- Meier method for up to 18 years of follow-up. Freedom from structural valvular distunction after mitral replacement was 89% at 6 years, 77% at 8 years, S6% at 10 years,31% at 12 years, 16% at 1s years, and 15% at 18 years. (Am J Cardiol lBB2;70:1157-1163) From the Departments of Cardiology,Pathology, and Cardiovascular Surgery, University of Padova Medical School, Padova, Italy. This study was supported by National Council for Research, Target Proj- ect “Aging,” Rome, Italy. Manuscript received February 21, 1992; revised manuscript received and accepted June 29,1992. Address for reprints: Paola Melacini,MD, Department of Cardiol- ogy, Via Giustiniani, 2, 35100 Padova, Italy. P orcine bioprostheses became commercially avail- able in 1970, and a large quantity of evidence has since shown that they have a satisfactory hemo- dynamic performance and a low rate of thromboembo- lism, but a poor durability. One particular problem is the potential risk for tissue degeneration that is charac- terized by leaflet disruption or calcium deposition, or both, and may result in hemodynamically significant re- gurgitation or stenosis, or both.1-5 Therefore, patients with bioprosthetic valves need careful follow-up to eval- uate the timing of reoperation. To this end, echocardi- ography appears to be the noninvasive technique of choic&13; 2-dimensional echocardiography provides an- atomic information on the status of the cusps, whereas Doppler studies and color flow imaging may help in as- sessing functional status.’ The object of this study was to delineate the characteristics of normally functioning Hancock bioprostheses and detect degenerated and mal- functioning valves, as well as to predict the time of fur- ther dysfunction in individual patients. We used 2-di- mensional and Doppler echocardiography to evaluate 134 patients in whom a Hancock bioprosthesis had been implanted in the mitral position 1 to 216 months before examination. METHOD8 SW popubtkn (retrorpeetive analysis): From January 1985 to February 1990, 134 patients with a Hancock bioprosthesis in the mitral position were stud- ied. In each case, a physical examination was per- formed, as well as M-mode, 2-dimensional and Doppler echocardiography; color flow imaging studies were rou- tinely initiated in April 1989. These patients constitute 31% of our entire case series that underwent Hancock valve implantation from 1970 to 1990, and comprise 36 men and 98 women (age range 35 to 76 years, mean 57 f 9) who were followed up for I1 8 years (116 f 47 months) after initial valve replacement. Echocardio- graphic evaluation was performed at least once a year. Valve replacement surgery was subsequently per- formed in 33 patients with dysfunctioning bioprostheses. Pathologic findings were considered the reference stan- dard against which echocardiography and Doppler stud- ies were matched. Echocardiography: We used a phased-array ultra- sound system (Hewlett-Packard 77020 AC and Sonos 1000 77030 A), 1 equipped with Duplex 2.5 and 3.5 MHz transducers, and an independent Pedoff for imag- ing, spectral Doppler and color flow mapping. The color flow Doppler system was set to maximum packet size ECHOCARDlOGRAPHlC DOPPLER MONITORING OF HANCOCK PROSTHESES 1157