NONINVASIVE EVALUATION OF LEFT-VENTRICULAR DIASTOLIC FUNCTION IN HYPERTROPHIC CARDIOMYOPATHY

Diastolic dysfunction is common in hypertrophic cardiomyopathy (HC). P revious studies suggest that Doppler transmitral flow velocity profile s, and the left atrial (LA) M-mode echogram can be used noninvasively to evaluate left ventricular (LV) diastolic function. However, this ha s not been proved in HC. In this study we determined the relation of D oppler transmitral flow velocity profiles and the LA M-mode echograms to invasive indexes of LV diastolic function in patients with HC. We s tudied 25 patients with HC, while off drugs, and calculated LA global and active fractional shortening and the slope of both early and late displacement of the posterior aortic wall during LA emptying by M-mode echocardiography. We calculated peak velocity of early (E) and atrial (A) filling, E to A ratio, and E-wave deceleration time by pulsed Dop pler echocardiography, and simultaneous radionuclide angiography, LV p ressures, time constant of isovolumic relaxation tau, and the constant of chamber stiffness k by cardiac catheterization. The time constant of isovolumic relaxation tau correlated with the slope of early poster ior aortic wall displacement (r = 0.59; p <0.01). LV end-diastolic pre ssure correlated with global LA fractional shortening (r = -0.75; p <0 .001); the constant of chamber stiffness k correlated with active LA f ractional shortening (r = -0.53; p <0.02). In a subset of 13 patients, in whom echocardiography and cardiac catheterization were performed s imultaneously, similar results were found, LA M-mode recordings provid e a more reliable noninvasive assessment of diastolic function in HC t han mitral Doppler indexes. (C) 1998 by Excerpta Medica, Inc.