Abstract: Abstract Objective: to evaluate the left cardiac function and hemodynamic performance of Mosaic bioprosthesis in mitral valve replacement for mitral stenosis Methods: from January 2010 to December 2010,thirty-three patients underwent mitral valve replacement with Mosaic bioprothesis in hospital. Doppler echocardiograms were recorded before operation 、3 month and 1 year after valve replacement. Result：After operation，left atrium diameter (LAD)[（38.9±5.4）mm vs（51.7±8.7）mm]，left ventricular diastolic diameter(LVDD) [（49.4±5.8）mm vs（54.5±8.2）mm]，left ventricular systolic diameter(LVSD) [（33.0±5.0）mm vs（38.5±6.5）mm]， Pulmonary artery pressure (PAP) [（31.1±5.1）mmHg vs（44.3±8.1）mmHg] were significantly different between preoperation and postoperation at 1 year. Conclusions: The Mosaic bioprosthesis demonstrates excellent clinical performance after 1 year of follow-up.

Key words: Mosaic, valve replacement, hemodynamic, bioprosthesis