Measurement of mitral orifice area in patients with mitral valve disease by real time, two dimensional echocardiography

Abstract

A quantitative assessment of mitral valve orifice area can be achieved in patients with pure mitral stenosis by cardiac catheterization. In the presence of mitral regurgitation, however, accurate measurement often is impossible because total diastolic flow through the mitral valve is frequently unknown. Using a recently developed real time, 2 dimensional echocardiography system, it is possible to obtain cross sectional images of the mitral valve, by scanning the heart perpendicular to its long axis at the level of the tip of the mitral leaflets. 20 Consecutive patients undergoing operation for mitral valve disease were studied during the wk prior to operation. In 18 of 20 (90%), the mitral orifice was imaged successfully in early diastole by 2 dimensional echocardiography so that mitral valve orifice area could be measured directly in square centimeters. In 14 patients (10 with associated mitral regurgitation), mitral orifice area was measured both by echocardiography and directly at time of operation. In 12 of 14 (86%) patients, mitral orifice area by 2 dimensional echocardiography was within 0.3 cm2 of that measured at operation (correlation coefficient for all 14 patients = 0.92). 2 Dimensional echocardiography is extremely useful in the evaluation of patients with mitral valve disease, because it provides a noninvasive method for directly measuring the mitral valve orifice area, that is accurate even in the presence of mitral regurgitation.