Two-Dimensional Speckle Tracking Echocardiography as Predictor of Major Adverse Cardiac Events in Patients With Non–ST-Elevation Myocardial Infarction and Unstable Angina

Abstract

INTRODUCTION: This study was conducted to determine the utility of two-dimensional speckle tracking echocardiography (2D STE) in predicting major adverse cardiac events (MACEs) in patients with non–ST-elevation acute coronary syndrome (NSTE-ACS).  METHODOLOGY: This is a prospective cohort study that included 91 patients diagnosed to have NSTE-ACS. In-hospital and 6-month MACEs were evaluated in relation to their baseline echocardiographic parameters, 2D speckle strain, and strain rate analyses.  RESULTS: Among the conventional echocardiographic parameters, only left ventricular end systolic diameter (LVESD) and wall motion scores showed significant difference between those with and without outcomes after 6 months. Significant higher wall motion scores (24.06 vs 20.91 P = 0.0320) and LVESD (3.36 vs 2.97 cm, P = 0.0125) were noted among those who had MACE after 6 months. There were no significant differences among the 2D STE strain and strain rate between those patients with and without MACE during their hospital admission. However, after 6-month follow-up, significantly lower mean left ventricular global longitudinal strain (GLS) −14.22% ± 4.45% vs −16.44% ± 4.19%, P = 0.0261) and strain rate (−0.69 ± 0.36 s-1 vs −0.94 ± 0.25 s-1, P = 0.009) were observed among patients with MACE compared with those without. Incidence of reduced GLS strain and strain rate was significantly higher in those with MACE after 6 months. Left ventricular GLS sensitivity and specificity were 64.64% and 61.70%, respectively, at a cutoff value of less than −15.0% for detecting MACE within 6 months. Left ventricular GLS cutoff point less than −12.0%, which detects severe LV dysfunction in previous studies, have a sensitivity of 40% but a high specificity of 82.98% for predicting MACE after 6 months.  CONCLUSION: Both LV GLS strain and strain rate can be used to predict major adverse cardiovascular events after NSTE-ACS.  KEYWORDS: speckle tracking echocardiography, non–ST-elevation acute coronary syndrome, cardiac events