Abstract
BACKGROUND: Diagnosing non-ST-segment elevation acute coronary syndrome (NSTE-ACS) is not always straightforward. Left ventricular global longitudinal strain (LVGLS) is an echocardiographic method capable of detecting subclinical regional and global ventricular contractile dysfunction due to myocardial ischemia. The objectives of this study were to evaluate the efficacy of LVGLS in diagnosing severe coronary disease in patients with chest pain suggestive of NSTE-ACS and to assess the relationships between LVGLS reduction and ultrasensitive troponin T (UsTnT) elevation, electrocardiographic changes suggestive of ischemia, and the number of vessels with severe obstructions. METHODS: This prospective, observational study evaluated hospitalized patients with chest pain of presumed coronary etiology. All patients underwent electrocardiography (ECG), UsTnT measurement, Doppler echocardiography, LVGLS measurement, and coronary angiography Coronary angiogram (CA) within 48 h of hospitalization. RESULTS: A total of 75 patients with a mean age of 58 ± 17 years were included, of whom 84% (63 patients) were men. An LVGLS value of <-16.5, as determined by the Youden index proved to be useful for the detection of severe coronary obstructions (lesions >70%). The sensitivity, specificity, and positive and negative predictive values were 96%, 88%, 92%, and 92%, respectively. The number of coronary arteries involved had a direct relationship with the degree of LVGLS reduction (P < 0.001). Elevated UsTnT levels occurred more frequently in patients with reduced LVGLS than in those with normal LVGLS (83% vs. 17%, P < 0.0001). Abnormal strain was not associated with electrocardiographic changes suggestive of ischemia. CONCLUSIONS: LVGLS measurement in patients with presumed NSTE-ACS is efficient in predicting the presence of severe coronary disease. The number of coronary arteries involved has a direct relationship with the degree of LVGLS reduction. Abnormal strain is associated with UsTnT elevations but not with electrocardiographic changes suggestive of ischemia.