斑点追踪技术评价右心室压力负荷对左心室心肌力学的影响

Evaluation of the effects of right ventricular pressure load on left ventricular myocardial mechanics by speckle tracking technology

目的应用斑点追踪技术评价右室压力负荷增加对左室心肌力学的影响，早期发现肺动脉高压患者左室功能的变化，为临床早期干预提供依据。方法肺动脉高压患者74例为病例组，据肺动脉收缩压（PASP）分为轻、中、重度组，分别以A、B、C组标识，对照组为年龄、性别相匹配的健康志愿者40例。均行超声心动图检查，测量常规超声心动图参数及左室各节段收缩期纵向、径向、环向峰值应变（LS、RS、CS），计算左室整体收缩期纵向、径向、环向应变（GLS、GRS、GCS），游离壁（侧壁＋后壁）及室间隔（前间隔＋后间隔）总体LS、RS、CS；测量基底段、心尖段心肌旋转角度峰值及达峰时间。分析并比较各组测量结果。结果①左室射血分数（LVEF）：A、B、C组较对照组无明显减低（P〉0．05）；②左室游离壁和室间隔整体LS、RS、CS以及左室GLS、GRS、GCS：B、C组低于正常对照组及A组，C组低于B组（P〈0．05）；③左室基底段及心尖段旋转角度：B、C组低于正常对照组及A组，C组低于B组（P〈0．05）；④A组GLS、GRS、GCS，游离壁及室间隔整体LS、RS、CS与正常对照组比较。差异无统计学意义（P〉0．05），但A组左室基底段旋转角度低于正常对照组（P〈0．05）。结论右室压力负荷增高可导致左室心肌力学受损，左室应变的改变早于LVEF。左室应变随右室压力负荷增高逐渐减低。左室基底段旋转角度能发现轻度肺动脉高压患者左室心肌力学的变化，较其他应变参数敏感。

Objective To evaluate the effects of right ventricular pressure load on left ventricular （LV） myocardial mechanics using speckle tracking technology, and to detect the change of LV function in patients with pulmonary hypertension（PH） at a earlier stage, in order to provide reference for early clinical intervention. Methods The study included 74 patients with PH and 40 healthy volunteers, who had of similar age and sex distribution. According to the pulmonary artery systolic pressure （PASP）, patients with PH were divided into mild, moderate and severe groups, which were marked with A, B, C, respectively. All subjects underwent echocardiographic examination. Conventional echocardiographic parameters, the systolic longitudinal, radial and circumferential peak strain （LS, RS, CS） in various segments of LV, as well as basal and apical segment myocardial rotation angle peak and peak time were determined, LV systolic global longitudinal, radial and circumferential strain （GLS, GRS, GCS）, free wall （LAT, lateral wall ＋ posterior wall） and interventricular septum （IVS, anteroseptal ＋ posteroseptal） overall LS, RS, CS were calculated. Results （1）LV ejection fraction （LVEF） ：group A, B, C had no significant reduction （ P 〉0.05） than the control group. （2）Overall LS, RS, CS of LAT of LV and IVS and GLS, GRS, GCS of LV： B, C group were lower than the control group and group A and C were lower than group B （ P 〈0.05）. （3）The rotation angle in ventricular apical basal segments and segment ： group B and C were lower than the control group and group A and C were lower than group B （ P 〈0.05）. （4）GLS, GRS, GCS and overall LS, RS, CS of LAT and IVS were similar between group A and the control group（ P 〉0.05）, but LV base segment rotation of group A was lower than that of the control group （ P 〈0.05）. Conclusions （1）Right ventricular pressure overload can lead to increased LV mechanical damage, LV strain changes were earlier than the change of LVEF. （2）LV strain with increased right ventricular pressure overload is gradually reduced. （3）Compared with other strain parameters, LV basal segments rotation angle were able to detect changes of LV myocardiol mechanics in patients with PH more sensitively.