组织追踪成像评价冠心病患者心肌收缩期后收缩的特征

目的:采用组织追踪成像(tissue tracking imaging,TTI)评价冠状动脉(冠脉)疾病患者心肌收缩期后收缩(post-systolic shortening,PSS)的特征。方法:选取54例因胸痛住院行冠脉造影的患者,术前3 d接受TTI检查,并根据其冠脉造影结果分为对照组(28例)和冠脉狭窄组(26例)。PSS指标包括收缩期后位移(postsystolic displacement,Dpss)、收缩期后位移指数(post systolic displacement index,PSI)及PSS检出率。结果 :对照组和冠脉狭窄组患者的PSS检出率分别为19.5%和32.5%(P<0.05),冠脉狭窄组的Dpss和PSI平均值显著高于对照组(P均0.23为截点值,即24个节段中有≥6个节段检出PSS时,TTI预测冠脉狭窄的灵敏度为73.1%,特异度为71.4%。结论:TTI检查对于冠脉狭窄患者的PSS检出率较高,且PSS波峰较高大。TTI检查能显示PSS的特征,帮助诊断冠脉疾病。

Characteristics of myocardial postsystolic shortening detected by tissue tracking imaging in patients with coronary artery disease

Objective To assess the characteristics of postsystolic shortening （PSS） of myocardium by tissue tracking imaging （TrI） in patients with coronary artery disease （CAD）. Methods Fifty-four subjects suspected of having CAD and having coronary angiography （CAG） performed were enrolled. They were divided into 2 groups according to CAG results. Patients in control group had normal coronary angiogram （n=28）, whereas patients in CAD group had ≥75% stenosis in at least 1 major coronary artery （n=26）. TYI was performed 3 days before CAG and 24 myocardial segments per left ventricle were analyzed. The number of segments having PSS was counted and postsystolic displacement （Dpss） and post systolic displacement index （PSI） were calculated as PSS-related parameters. Results The incidences of PSS in control group and CAD group were 19.5% and 32.5%, respectively （P〈0.05）. The mean values of Dpss and PSI in CAD group were significantly higher than that in control group （both P〈0.05）. ROC analysis showed that using PSS rate 〉0.23, or PSS occurred in ≥6 among the 24 segments, as the cutoff value, the sensitivity of identifying significant coronary stenosis was 73.1% and the specificity was 71.4%. Conclusions PSS occurs significantly more often and with a greater magnitude in patients with CAD. TrI may be useful for identifying the characteristics of PSS and be helpful to diagnose CAD.