Layer-Specific Quantification of Myocardial Deformation by Strain Echocardiography May Reveal Significant CAD in Patients With Non-ST-Segment Elevation Acute Coronary Syndrome

作者：Sarvari Sebastian I; Haugaa Kristina H; Zahid Wasim; Bendz Bjorn; Aakhus Svend; Aaberge Lars; Edvardsen Thor^*

来源：JACC: Cardiovascular Imaging , 2013, 6(5): 535-544.

DOI：10.1016/j.jcmg.2013.01.009

• coronary artery disease
• echocardiography
• myocardial function
• myocardial layers
• strain

OBJECTIVES Our objective was to assess whether patients with significant coronary artery disease (CAD) had reduced endocardial function assessed by layer-specific strain compared with patients without significant CAD.
BACKGROUND The left ventricular (LV) wall of the heart comprises 3 myocardial layers. The endocardial layer is most susceptible to ischemic injury.
METHODS Seventy-seven patients referred to coronary angiography due to suspected non-ST-segment elevation-acute coronary syndromes (NSTE-ACS) were prospectively included. Coronary occlusion was found in 28, significant stenosis in 21, and no stenosis in 28 patients. Echocardiography was performed 1 to 2 h before angiography. Layer-specific longitudinal and circumferential strains were assessed from endocardium, mid-myocardium, and epicardium by 2-dimensional (2D) speckle-tracking echocardiography (STE). Territorial longitudinal strain (TLS) was calculated based on the perfusion territories of the 3 major coronary arteries in a 16-segment LV model, whereas global circumferential strain (GCS) was averaged from 6 circumferential LV segments in all 3 layers.
RESULTS Patients with significant CAD had worse function in all 3 myocardial layers assessed by TLS and GCS compared with patients without significant CAD. Endocardial TLS (mean -14.0 +/- 3.3% vs. -19.2 +/- 2.2%; p < 0.001) and GCS (mean -19.3 +/- 4.0% vs. -24.3 +/- 3.4%; p < 0.001) were most affected. The absolute differences between endocardial and epicardial TLS and GCS were lower in patients with significant CAD (Delta 2.4 +/- 3.6% and Delta 6.7 +/- 3.8%, respectively) than in those without significant CAD (Delta 5.3 +/- 2.1% and Delta 10.4 +/- 3.0%; p < 0.001). This reflects a pronounced decrease in endocardial function in patients with significant CAD. A receiver-operating characteristic curve analysis showed that endocardial and mid-myocardial TLS were superior to identify significant CAD compared with epicardial TLS (p < 0.05), wall motion score index (p < 0.01), and ejection fraction (EF) (p < 0.001).
CONCLUSIONS Assessment of layer-specific strain by 2D-STE might identify NSTE-ACS patients with significant CAD. Endocardial function was more affected in patients with significant CAD compared with epicardial function and EF.

• 出版日期2013-5