Echocardiographic Measurement of Early Diastolic Time Intervals in Patients with Hypertension: With Reference to Regional Nonuniformity and Restoring Forces

ABSTRACT

BACKGROUND: It is known that left ventricular(LV) wall motion is not uniform even in normal heart, and the restoring forces make phase differences between LV wall motion and mitral flow velocity during rapid filling period. METHOD: To investigate the regional nonuniformity and restoring forces in 46 patients with hypertension(HT)(groupnormal wall thickiness.n=12,IILVH with fractional shortening(FS)>25%. n=22. IIIFS<25%.n=12). We measured the time intervals from A2 to peak thinning rate point of LV posterior wall(A2-(-)dpw/dt).to mitral flow starting point (IRT).and to peak mitral flow velocity(A2-E) by M-mode and Doppler echocardiography. RESULTS: The noniformity((-)dpW/dt-dL/dt)and phase differance((-)dpw/dt-E) were increased in HT(controlHT.22+/-7.8 vs. 49+/-5.2msec, 63+/-4.5 vs, 86+/-6.2msec, p<0.05 respectively).In group comparison, nonuniformity increased in group II and III(group I group II, III, 35+/-5.1 vs. 50+/-7.1,70+/-14msec, p<0.05 respectively). but phase difference increased only in group II(groupII group I, III, 93+/-6.0 vs. 75+/-5.2, 80+/-20msec, p<0.05, respectively). CONCLUSION: We interpreted these data that in HT with hypertrophy or not, the nonuniformity of LV wall motion working on the restoring forces which can be expressed as phase difference between LV wall motion and mitral flow. But in HT with hypertensive heart failure group, no significant changes of phase difference and it's suggest that other mechanism could be also working on early diastolic filling.