双脉冲多普勒超声评价健康人群左右心室机械做功的顺序

摘要

目的:应用双脉冲多普勒超声心动图技术观察健康人群中左、右心室收缩期及舒张期机械做功的顺序.方法:选取100例健康志愿者,分别取双流出道切面和心尖四腔切面,应用双脉冲多普勒技术在同一心动周期同步记录左心室流出道、右心室流出道血流频谱和左心室流入道、右心室流入道血流频谱,分别测量心电图QRS波群顶点至主动脉、肺动脉、二尖瓣和三尖瓣血流频谱起始的时间间期,计算主动脉和肺动脉血流频谱、二尖瓣和三尖瓣血流频谱起始时间的差值,进而评估左、右心室收缩和舒张机械做功的顺序.结果:48例左心室先于右心室射血,占48%(95%CI:0.38~0.58);46例右心室先于左心室射血,占46%(95%CI:0.36~0.56);6例左、右心室同时射血,占6%(95%CI:0.01~0.11).96例右心室先于左心室充盈,占96%(95%CI:0.90~0.99);3例左心室先于右心室充盈,占3%(95%CI:0.01~0.08);1例左、右心室同时充盈,占1%(95%CI:0.00~0.05).结论:健康人群的左、右心室收缩期及舒张期做功顺序,具有一定的规律:收缩期做功顺序因人而异,但舒张期做功顺序,右心室始终在前.根据正常状态下心室间机械做功的顺序优化起搏器程控参数,选择优化舒张期心脏做功顺序,可能是未来心脏再同步治疗(CRT)起搏器参数优化的终点指标.%Objective: To observe left and right ventricular mechanical sequence in systole and diastole by dual Doppler Echocardiography in healthy subjects. Methods: Dual Doppler echocardiography was performed in 100 normal subjects with dual-outflow-tract-view and apical four chamber view to simultaneously record the spectrum of left/right ventricular outlfow tract (LVOT)/(RVOT) and left/right ventricular inlfow tract (LVIT)/(RVIT) at the same cardiac cycle. The time cycles of blood lfow spectrum from the peak of QRS complex to aorta, pulmonary artery, mitral valve (MV) and tricuspid valve (TV) were measured, the starting time differences for blood lfow spectrum of aorta and pulmonary artery, MV and TV were calculated to assess the mechanical sequence of left and right ventricle in systole and diastole respectively. Results: There were 48/100 (48%) subjects having LV ejection preceded than RV (95% CI 0.38-0.58), 46 (46%) having RV ejection preceded than LV (95% CI 0.36-0.56) and 6 (6%) having LV, RV simultaneous ejection (95% CI 0.01-0.11). There were 96/100 (96%) subjects having RV iflling prior to LV (95% CI 0.90-0.99), 3 (3%) having LV iflling prior to RV (95% CI 0.01-0.08) and 1 (1%) having LV, RV simultaneous iflling (95% CI 0.00-0.05). Conclusion: There is a regular pattern for mechanical sequence of LV and RV in systole and diastole in healthy subject; in systole, the sequence of LV varies from person to person, while in diastole, RV is always preceded. Based on normal ventricular mechanical sequence, optimizing programming parameter of pace maker and choosing cardiac sequence in diastole might be the ifnal criteria for cardiac resynchronization therapy in the future.