Fig. 9

Mitral Regurgitation (continued). Quantification of mitral regurgitant volume in the case shown in Fig. 8 was done by subtracting the forward stroke volume across the aortic valve by PC-CMR from the total LV stroke volume. LV stroke volume is computed by using any of a number commercially-available software packaged (Argus, Siemens shown) to delineate endocardial borders at end-systole and end-diastole in each of the contiguous short axis cine CMR planes covering the length of the LV. The difference in volumes computed using Simpson’s rule is the LV stroke volume. In this patient, the mitral regurgitant volume was 100 (LV stroke volume by cine CMR) – 45 (aortic stroke volume by PC-CMR) = 55 mL, or a regurgitant fraction of 55 % consistent with severe mitral regurgitation