The myocardial performance index in patients with aortic stenosis

OBJECTIVES: This study was designed to determine the effect of chronic afterload on a Doppler-derived myocardial performance index (MPI) combining both systolic and diastolic left ventricular dysfunction. METHODS: The study included 36 patients with a diagnosis of aortic stenosis and 36 normal subjects. Doppler-derived myocardial performance index (MPI), defined as the sum of the isovolumic contraction time and isovolumic relaxation time divided by ejection time, was measured from the mitral valve inflow and left ventricular outflow velocity patterns and was then related to the aortic valve area, valve gradient, and other echocardiographic variables. RESULTS: The values of the Doppler-derived MPI in the patients with aortic stenosis were significantly higher than those in the controls (0.54 +/- 0.20 vs 0.38 +/- 0.04, respectively; P < 0.001). Transmitral deceleration time and the E/A ratio ( r = 0.47 and r = 0.35, respectively; P < 0.05) were significant univariate correlates, and mitral deceleration time was the only significant correlate of MPI. However the index did not correlate with aortic valve area, peak and mean valve gradients, left ventricular mass, or age. CONCLUSIONS: Doppler-derived MPI reflects severity of global left ventricular dysfunction in patients with aortic stenosis and may be of clinical value in this patient population.