Left atrial size, pressure, and V wave height in patients with isolated, severe, pure mitral regurgitation.

In recent years, some concepts regarding the etiology and hemodynamics present in the syndrome of mitral regurgitation have changed. Coronary artery disease and mitral valve prolapse have replaced rheumatic heart disease as the most frequent cause of mitral regurgitation. Hemodynamic studies have shown that tall V waves in the pulmonary capillary wedge tracings are neither specific nor sensitive in detecting the presence of mitral regurgitation. In this study, we evaluated the role of various clinical, echocardiographic, and hemodynamic findings with regard to left atrial (LA) size, pressure, and V wave height. We found that the mean pulmonary capillary wedge pressure (PCW) and V wave height for the subset of patients with acute mitral regurgitation (PCW = 24.1 +/- 10.9; V = 41.2 +/- 20.7 mm Hg) was similar to the subset with chronic mitral regurgitation (PCW = 17.9 +/- 7.5; V = 32.0 +/- 18.2 mm Hg). In addition, we found that there was a significant logarithmic relationship between the LA size and the duration of the mitral regurgitation (y = 1.404 [log X] + 3.948; R = 0.678; p less than 0.0005). Lastly, we found that LA size, compliance, regurgitant volume, and regurgitant valve orifice area all increase with time.