Identification of severe coronary stenosis by two-dimensional strain in acute coronary syndrome without ST segment elevation.

Abstract

Background: The main objective of our study was to identify, by means of global longitudinal strain (GLS), territorial strain (TS), and postsystolic shortening (PSS) of left ventricle, which patients with acute coronary syndrome without ST elevation (NSTE-ACS) had ≥ 70% coronary stenosis. Methods: One hundred patients (PTS) with diagnosis of NSTE-ACS were stratified according to GRACE risk score, and underwent coronary angiography. GLS and TS were calculated. We also evaluated the strain curves in the 18 segments to identify the presence of the PSS and to calculate the post systolic index (PSI). Results: Mean age was 60 ± 11. 4, 62% was male. The majority were low and moderate cardiovascular risk. They were divided into group A (34 PTS) with coronary stenosis<70% and group B (66 PTS) with coronary stenosis ≥ 70%. Clinical score was higher in group B (GRACE=88. 7 ± 24. 18, p=0. 040) and 98. 5% was in low/moderate risk by GRACE score. GLS allowed the identification of PTS with coronary stenosis ≥ 70% in this group (AUC=0. 72, p=0. 001, sensitivity=58%, specificity=88%, positive predictive value=75. 1% and negative predictive value=74. 9%). Regarding the TS, the accuracy to determine coronary stenosis ≥ 70% was 0. 70 (p=0,001). The accuracy of the PSS in detecting coronary stenosis ≥ 70% was 69. 3%, with sensitivity estimated at 73. 3% and specificity at 60. 7%. Conclusion: The GLS, territorial strain, and PSS may improve the detection of severe coronary stenosis in patients with low/moderate risk by GRACE risk score. Thus, it can be an additional tool for a better stratification of such patients in the emergency unit.