Abstract 11678: Early Strain Echocardiography May Exclude Significant Coronary Artery Stenosis in Suspected Non-ST-Elevation Acute Coronary Syndrome
Background: Many patients with suspected non-ST-elevation acute coronary syndrome (NSTE-ACS) have no significant coronary artery disease. Current diagnostic approach with repeated ECG and cardiac biomarkers requires observation for at least 6-12 hours. The aim of this study was to investigate whether global strain by echocardiography measured at admission may exclude significant coronary artery stenosis in patients presenting with inconclusive ECG and normal cardiac biomarkers.
Methods: Patients without known coronary artery disease presenting with suspected NSTE-ACS were enrolled consecutively. 12-lead ECG, Troponin t assay and echocardiography was performed on admission and patients underwent coronary angiography after 27±18 hours. Conclusive ECG was defined as >1 mm ST-segment change in any lead. Troponin t >0.03 µg/L was considered abnormal and >50 % stenosis of any coronary artery was considered significant. Echocardiography was analyzed by a single observer blinded to patient data. Global peak systolic longitudinal strain was measured using speckle tracking echocardiography in the 3 apical image planes and calculated by averaging all segments in a 16 segment model. Ejection fraction (EF) and wall motion score index (WMSI) were calculated.
Results: Out of 86 patients (age 60±13 years, 71 % male) 41 patients presented with inconclusive ECG and normal cardiac biomarkers. No significant stenosis in any coronary artery was found in 17 (41%) of these patients. A global peak systolic longitudinal strain value of <-21% excluded significant coronary artery stenosis with 77% sensitivity and 92 % specificity (AUC = 0.90) (figure).
Conclusions: Strain by echocardiography may become an accurate and easily available tool to exclude significant coronary artery stenosis among patients presenting with suspected non-ST-elevation acute coronary syndrome with inconclusive ECG and normal cardiac biomarkers.
- © 2011 by American Heart Association, Inc.