This study was designed to define the role of left atrial (LA) wall motion during left ventricular (LV) diastolic phase for patients with pseudonormal mitral inflow. We perform the M-mode of posterior aortic, indicating LA, wall motion, and Doppler echocardiography following cardiac catheterization among 71 patients with a ratio of early (E) to late mitral flow (A) >1. The amplitude of total LA wall motion (TM), early LA rapid emptying (EM), and late LA emptying (AM) during the LV diastolic phase were all derived from M-mode analysis. Study patients were classified into two distinct groups according to the LV end-diastolic pressure (EDP): patients with a LVEDP value < 15 mmHg (n = 36, normal group), and patients with a LVEDP value > or = 15 mmHg (n = 35, pseudonormal group). Values of AM (4.7 +/- 1.2 vs 5.5 +/- 1.2 mm) and AM/TM (0.43 +/- 0.07 vs 0.55 +/- 0.08) for the normal and pseudonormal groups, respectively, were significantly higher for the pseudonormal group, whereas EM (6.6 +/- 1.8 vs 4.8 +/- 1.4 mm), TM (11 +/- 3 vs 10 +/- 2 mm), EM/AM (1.41 +/- 0.46 vs 0.91 +/- 0.28), EM/TM (0.58 +/- 0.10 vs 0.48 +/- 0.07) were significantly higher for the normal group. Among these parameters, AM/TM correlated best with the time constant of LV isovolumic relaxation (r = 0.77, P < 0.001). Using an AM/TM ratio value of >0.5 as an indicator of LV diastolic function abnormality, the sensitivity, specificity, positive predictive values, and negative predictive values for the detection of pseudonormalization were 85%, 94%, 94%, and 87%, respectively. These findings suggest that the increased volume reduction of late LA emptying (AM/TM) during LV diastolic phase assessed by M-mode echocardiography is useful for evaluating pseudonormal mitral inflow.