Abnormalities of the left ventricular diastolic function can be classified by pulsed Doppler echocardiography, but sometimes it may be difficult to differentiate normal diastolic function from pseudonormalization. Heart failure caused by increased left ventricular filling pressure is rather associated with pseudonormalization or restrictive pattern than normal pattem or relaxation abnormality. We investigated the usefulness of color M-mode Doppler echocardiographic indexes in differentiating normal relaxation from pseudonormalization after acute myocardial infarction.

Echocardiographic examination including color M-mode Doppler was performed in 44 patients with acute myocardial infarction between 10 and 14 days after attack. 34 patients without in-hospital congestive heart failure(CHF) were assigned as group I, and 10 patients with in-hospital CHF as group II. Flow propagation slope(FPS), time difference(TD) between the occurrence of peak flow velocity in the apical region and at the mitral tip, and normalized time difference(nTD) by mitral and apical distance were measured with color M-mode Doppler echocardiography.

FPS was lower in group II(group I, 42.0±20.6cm/sec vs group II, 27.8±8.0cm/ sec , p=0.065). Both groups had similar TD and nTD. FPS was compared in patients with E/ A ratio of mitral inflow greater than 1(22 patients of group I and 7 patients of group II). Patients with E/A) 1 in group II had significantly lower FPS(group I, 52.1±17.5cm/sec vs group II, 31.0±7.4cm/sec ; p(0.01).

FPS was significantly decreased after acute myocardial infarction in patients with in-hospital CHF compared with patients without in-hospital CHF, even when E/A ratio of mitral inflow was greater than 1. Therefore, FPS was an useful index in differentiating normal relaxation from pseudonormalization.