Exercise echocardiography in the evaluation of functional mitral regurgitation: a systematic review of the literature.

BACKGROUND The aim of this article is to present a systematic review of publications regarding the role of exercise echocardiography in the evaluation of functional mitral regurgitation. METHODS The PubMed database was searched using the following combination of keywords: "mitral" and "regurgitation" and "exercise" and "echocardiography". Initially, a list of 152 articles published between 1977 and 2007 was retrieved. Following application of the exclusion criteria, the list was shortened to 18 original scientific papers. Different groups of patients were analyzed in these studies, but mainly patients with ischemic left ventricular systolic dysfunction with at least mild mitral regurgitation were included. All participants underwent echocardiography, which included resting examination and certain stress tests, i.e. exercise tests using a cycloergometer or a treadmill as well as pharmacological stress. The main evaluated echocardiographic parameters were regurgitant volume, effective regurgitant orifice area (ERO), left ventricular geometry and function, and systolic pulmonary artery pressure. RESULTS Exercise-induced changes in mitral regurgitation parameters were strongly associated with the risk of pulmonary edema, mortality, exercise tolerance and the severity of ischemic heart disease. The most important echocardiographic variable was an increase in ERO of more than 13 mm2 during exercise. CONCLUSIONS Published scientific evidence demonstrates the significance of exercise echocardiography in patients with functional mitral regurgitation in relation to its dynamic character, the possibility of a considerable increase in the severity of even mild mitral regurgitant jet with changing loading conditions and especially with increased left ventricular afterload. (Cardiol J 2007; 14: 436-446).