Background: Echocardiography is a first simple technique for the evaluation of coronary artery disease (CAD), which is useful in the diagnostic and prognostic workup of these syndromes. The clinical work-up of patients presenting with chest pain is a diagnostic challenge.
 Objective: We inspected the diagnostic performance of global (GLS) and territorial (TLS) longitudinal strain to predict CAD in patients presenting with suspected non-ST-segment elevation acute coronary syndrome (NSTE-ACS) but apparent normal global and regional systolic function.
Patients And Method: A cross sectional study included 90 patients with suspected NSTE-ACS with normal left ventricular ejection fraction (LVEF) (≥50%) and wall motion score index (WMSI) (=1). Speckle-tracking echocardiography was performed to all patients on admission then patients underwent coronary angiography or noninvasive test according to their risk stratification. Patients were classified to 2 groups (CAD and No CAD).
Results: There was significant sensitivity and specificity of cardiac enzymes, GRACE score, Global longitudinal strain and territorial longitudinal strain in identifying CAD. However there was no statistically significant difference in conventional echocardiographic data between both studied groups. A cutoff value of GLS -17.1, TLS-LAD cutoff level >-17.15, TLS-LCX cutoff level >-16.9 and TLS-RCA cutoff level >-16.3. GLS as a predictor for the number of affected vessels, cutoff point of ≥ -15.4 can be used. A predictor for the presence of proximal lesions, cutoff point of TLS LAD ≥ -15.1 and TLS LCX ≥-15.3 can be used.
Conclusions: Global longitudinal strain and territorial longitudinal strain can be used for early detection of the presence of coronary artery occlusion to identify patients who may benefit from early reperfusion. GLS also can predict multivessel disease and TLS can be used as a predictor for the presence of proximal lesions.