Abstract
Purpose: Mitral annular early-diastolic velocity (e´) and the early transmitral velocity to e´ ratio (E/e´) have been widely used as indexes of left ventricular (LV) relaxation and filling pressure, respectively. There are, however, a number of clinical settings in which e´ and E/e´ may not be reliable. We thus conducted a multicenter study in Japan (SMAP) to determine the accuracy of echocardiographic indexes of LV relaxation and filling pressure. Subjects and Methods: In 52 patients with various structural heart diseases from four institutions, time constant of LV pressure decay (τ) and LV mean diastolic pressure (LVMDP) were measured using a micromanometer-tipped catheter. Echocardiographic diastolic parameters were also measured. Results and Discussion: There was no difference in e´ between patients with and without abnormal relaxation. There was a weak, but significant, correlation between τ (48±11 msec) and e´ (r=-0.30, p=0.03), or deceleration time of pulmonary venous D wave (r=0.40, p=0.02). There was no difference in E/e´ between patients with and without elevated LV filling pressure. LVMDP (8.3±6.1 mmHg) significantly correlated with transmitral E/A (r=0.47, p=0.001), but not with E/e´ (r=0.27, p=0.053). Conclusion: The multicenter study in Japan demonstrated that e´ and E/e´ might be of limited use for estimating LV relaxation and filling pressure in patients with various structural heart diseases. Furthermore, e´ and E/e´ were not superior to the conventional indexes of LV inflow or pulmonary venous flow.
