Evaluation of transient mitral regurgitation in coronary artery disease

Abstract

The pathoanatomy and factors associated with transient mitral regurgitation (MR) induced by myocardial ischemic stress are unknown. Changes in valvular and ventricular parameters during transient, stress-induced MR in patients with coronary artery disease were investigated, and the clinical characteristics of these patients were identified. Color flow Doppler echocardiography was used to quantify the MR color area, the coaptation point of the mitral leaflets, the mitral valve anulus diameter, and left ventricular volumes and wall motion in 42 patients before and immediately after exercise echocardiography (group 1, n = 27), or before and during percutaneous transluminal coronary angioplasty (PTCA) (group 2, n = 15). Of the 27 patients with exercise echocardiography, 4 developed new, transient MR (group 1B) and 9 had MR both at rest and during exercise (group 1C). Of the 15 patients with PTCA, 7 developed new MR (group 2B). New MR (groups 1B and 2B) was associated with more severe stress-induced ventricular dyskinesia (p < 0.05) than was seen in patients with chronic MR (group 1C) or in patients without MR, and occurred predominantly in patients with left anterior descending or right coronary artery stenoses. Stress-induced MR was not associated with changes in blood pressure or in mitral valve anulus diameter, nor with the development of mitral valve prolapse. It was associated with apical displacement of the mitral leaflets in patients in group 1B and C (p < 0.05). New MR flow areas were significantly smaller than those in patients with chronic MR (p < 0.05). Thus, myocardial ischemic, stress-induced, transient MR is associated with ventricular dyskinesia and not with the development of mitral valve prolapse.