Cardiovascular Magnetic Resonance Characterization of Mitral Valve Prolapse Yuchi Han, Dana C. Peters, Carol J. Salton, Dorota Bzymek, Reza Nezafat, Beth Goddu, Kraig V. Kissinger, Peter J. Zimetbaum, Warren J. Manning, Susan B. Yeon Cardiovascular magnetic resonance (CMR) has not been previously used to characterize mitral valve prolapse (MVP). Cardiovascular magnetic resonance was compared to transthoracic echocardiography in 25 MVP patients and 25 controls. A 2-mm leaflet excursion into the left atrium on the left ventricular outflow view was 100% sensitive and specific for MVP. Leaflet thickness, length, and mitral annular diameters correlated well between CMR and transthoracic echocardiography. Of 16 MVP patients, 10 (63%) demonstrated late gadolinium enhancement of the papillary muscles consistent with fibrosis whereas no controls did. This is the first study to demonstrate fibrosis in vivo in the subvalvular apparatus in MVP patients.