实时三维斑点追踪显像技术评价心肌缺血患者左心室局部功能

目的 应用实时三维斑点追踪显像(3D-STI)技术评价冠状动脉左前降支(LAD)不同狭窄程度缺血患者左心室心肌局部应变变化。方法 根据冠状动脉造影(CAG)结果将138例临床疑诊冠心病患者分为对照组(34例)和狭窄组(104例),另将狭窄组分为轻度狭窄亚组(A亚组,n=34)、中度狭窄亚组(B亚组,n=36)和重度狭窄亚组(C亚组,n=34)。测量LAD供血区域心肌的应变指标:峰值径向应变(PLS)、峰值面积应变(PAS)、应变显像舒张指数(SI-DI),分析2D-STI及3D-STI测值的相关性。结果 对照组3D-STI的PLS较2D-STI值偏低(P<0.05),相关性良好(r值:0.58~0.76)。A亚组PAS与对照组相比差异无统计学意义(P>0.05)。与对照组比较,C亚组全部节段及B亚组前壁中间段及心尖段、前间隔中间段及前间隔心尖段的PAS值减低(P<0.05),C亚组全部节段及B亚组前壁基底段及心尖段、前间隔中间段及前间隔心尖段的SI-DI值减低(P<0.05);与B亚组比较,C亚组的前壁中间段及心尖段的PAS值减低(P<0.05),前壁中间段及心尖段和前间隔心尖段的SI-DI值减低(P<0.05)。结论 3D-STI可有效评估心肌缺血患者左心室局部心肌纤维早期形变特征。

Real-time three-dimension speckle tracking in assessment of left ventricular regional function in patients with myocardial ischemia

Objective To assess the alterations of regional strain in left ventricular (LV) ischemic myocardial segments in patients with different extent of left anterior descending artery (LAD) stenosis with real-time three-dimensional speckle tracking imaging (3D-STI). Methods One hundred and thirty-eight patients with clinically suspected coronary heart disease (CHD) were divided into control group (n=34) or stenosis group (n=108) according to coronary angiography (CAG), and those in stenosis group were divided into mild stenosis (A, n=34) subgroup, moderate stenosis (B, n=36) subgroup and severe stenosis (C, n=34) subgroup. STI was performed before CAG, and stain parameters of LV, including segmental systolic peak longitudinal strain (PLS), segmental systolic peak area of strain (PAS) and strain imaging diastolic index (SI-DI) were measured. The relation between 2D-STI and 3D-STI results was analyzed. Results Compared with 2D-STI, PLS of 3D-STI decreased (P<0.05), while good correlation was found between 2D-STI and 3D-STI in the control group (r: 0.58-0.76). Compared with control group, PAS of A subgroup were not statistically different (P>0.05), while of all segments in C subgroup, of mid anterior and mid anterosepta, as well as of apical anterior and apical anteroseptal in B subgroup were lower (P<0.05), SI-DI of all segments in C subgroup and basal anterior, mid anteroseptal, apical anterior and apical anteroseptal in B subgroup were lower (P<0.05). Compared with B subgroup, PAS of mid anterior and apical anterior in C subgroup were lower (P<0.05), SI-DI of mid anterior, apical anterior and apical anteroseptal in C subgroup were lower (P<0.05). Conclusion 3D-STI can effectively evaluate early changes of deformation characteristics of LV regional myocardial ischemia.