应变率显像技术对肺动脉高压患者右心室功能及收缩后收缩现象的评价作用研究

Evaluation of Right Ventricular Function and Postsystolic Shortening in Patients with Pulmonary Artery Hypertension by Strain Rate Imaging

目的探讨采用应变率显像技术评价不同程度的肺动脉高压患者右室收缩和舒张功能及收缩后收缩(PSS)现象的临床意义。方法选择2007年9月—2008年8月在我院门诊和住院接受治疗的肺动脉高压患者60例,包括轻度肺动脉高压组(A组,20例)、中度肺动脉高压组(B组,20例)及重度肺动脉高压组(C组,20例),选择同期健康志愿者为对照组(20例)。采用彩色多普勒超声现显像仪获得右室游离壁、后壁收缩期峰值应变率〔SRs,包括基底段收缩期峰值应变率(SRsb)和中间部收缩期峰值应变率(SRsm)〕及舒张早期应变率〔SRe,包括基底段舒张早期峰值应变率(SReb)和中间部舒张早期峰值应变率(SRem)〕,统计各组出现PSS的节段数,记录PSS值。结果 4组对象右室结构指标及心肌综合指数(Tei指数)比较,差异有统计学意义(P<0.05);对照组与肺动脉高压各组间收缩期峰值应变率及舒张早期应变率比较,差异有统计学意义(P<0.05);对照组与肺动脉高压各组间PSS比较,差异有统计学意义(P<0.05)。相关分析显示:PSS与右室前壁厚度(RVAW)、右室横径(RVD)、SRs、SRe及PASP均有相关性(r=0.659、0.437、-0.583、-0.623、0.630,P<0.05)。多因素逐步回归分析显示,RVAW是影响PSS的主要因素。结论肺动脉高压患者的右室功能减低,应变率显像技术可定量、准确地评价右室长轴功能;肺动脉高压患者病理性PSS出现提示肺动脉高压右室局部心肌节段存在相对心肌缺血;RVAW是影响肺动脉高压患者右室心肌PSS的主要因素。

Objective To explore the value of strain rate imaging （SRI） in evaluating right ventricular systolic and diastolic function and postsystolic shortening （PSS） in patients with varying degrees of pulmonary artery hypertension （PAH）. Methods A total of 60 patients with PAH treated in our hospital between Sep 2007 and Aug 2008 were selected, including 20 patients with mild PAH, 20 patients with moderate PAH and 20 patients with severe PAH. 20 normal subjects were chosen as the control group underwent SRI study. Systolic peak strain rate （SR） of right ventricular free wall, systolic peak SR in base and me- dian （ SRsb, SRsm） and early diastolic SR in base and median （ SReb, SRem） in four septal were measured by color doppler ul- trasonography. PSS segment numbers were counted and their amplitude were recorded in the four septal. Results Comparisons of myocardial performance index （Tei index） and right ventricular structural parameters between each group were significantly dif- ferent （P 〈 0. 05） . Differences of systolic peak strain rate, early diastolic strain rate and PSS between the control group and the groups of PAH were statistically significant （ P 〈 0. 05 ） . The correlation analysis of the structural parameters, function parame- ters and PSS showed that PSS was correlated with right ventricular anterior wall thickness （RVAW）, right ventricular diameter, SRs, SRe and parasphenoid （r = 0. 659, 0. 437, - 0. 583, - 0. 623, 0. 630, P 〈 0.05 ） . Multiple stepwise regression anal- ysis indicated that RVAW was the main factor affecting the PSS. Conehl^on Right ventricular function of patients with pulmonary hypertension decrease. SRI can assess right ventricular long axis function quantitatively and accurately. The occurenee rate of patho- logical PSS in PAH group may hint the existence of right ventricular regional myocardial segment relative myocardial isehemia.