Department of Cardiovascular Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
J Cardiol. 2011 May;57(3):311-5. doi: 10.1016/j.jjcc.2011.01.008. Epub 2011 Mar 8.
Post-ischemic myocardial diastolic stunning persists for a long time after transient ischemia even after systolic function has recovered. We sought to identify coronary artery stenosis in clinical patients using strain imaging diastolic index (SI-DI) at rest.
We retrospectively examined 85 patients with suspected coronary artery disease and preserved ejection fraction (EF; >50%) who underwent both echocardiography and coronary angiography. Speckle tracking strains were measured in 3 apical views and parasternal left ventricular (LV) short-axis views at the papillary muscle level. LV segments with inadequate image quality and deficit segments in the movie were excluded by the blinded observer. After strain analysis, LV segments were classified into no stenosis (≤ 50%), mild stenosis (51-75%), and severe stenosis (>75%) groups on the bases of the coronary angiogram.
SI-DI decreased significantly in severe stenosis segments (p<0.05, ANOVA), but none of the peak strains showed significant difference. The area under the curve for predicting severe stenosis in radial, longitudinal, and transverse SI-DI was 0.72, 0.74, and 0.80, respectively. A cut-off value of 49 for transverse SI-DI can predict LV segments with severe stenosis with sensitivity of 0.79 and specificity of 0.73. A screening cut-off value of 63 for transverse SI-DI shows sensitivity of 0.95 and specificity of 0.50.
SI-DI at rest is a novel marker in predicting coronary stenosis even in patients with preserved EF. This index can be used to screen patients with suspected coronary artery disease in routine echocardiography and does not require stress provocation.
短暂性缺血后，即使收缩功能已经恢复，心肌舒张性顿抑仍会持续很长时间。我们试图使用静息状态下应变成像舒张指数（SI-DI）在临床患者中识别冠状动脉狭窄。
我们回顾性检查了 85 名疑似冠心病和射血分数保留（EF>50%）的患者，这些患者均接受了超声心动图和冠状动脉造影检查。在 3 个心尖切面和心尖旁左心室（LV）短轴乳头肌水平切面测量斑点追踪应变。由盲法观察者排除图像质量不足和电影中的缺陷节段。在应变分析后，根据冠状动脉造影将 LV 节段分为无狭窄（≤50%）、轻度狭窄（51-75%）和重度狭窄（>75%）组。
重度狭窄节段的 SI-DI 显著降低（p<0.05，方差分析），但峰值应变均无显著差异。径向、纵向和横向 SI-DI 预测重度狭窄的曲线下面积分别为 0.72、0.74 和 0.80。横向 SI-DI 的截断值为 49 可预测 LV 节段存在重度狭窄，其敏感性为 0.79，特异性为 0.73。横向 SI-DI 的筛查截断值为 63 时，敏感性为 0.95，特异性为 0.50。
即使在 EF 保留的患者中，静息状态下的 SI-DI 也是预测冠状动脉狭窄的新标志物。该指数可用于常规超声心动图筛查疑似冠心病患者，且无需应激激发。
