Aims: Patients with acute coronary occlusion may lack typical signs of myocardial infarction in the electrocardiogram. We tested the ability of different echocardiographic modalities to identify coronary occlusion by quantifying myocardial dysfunction in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS).
Methods and results: One hundred and fifty patients were examined by echocardiography immediately prior to coronary angiography, 2.2 +/- 0.7 days (mean +/- SD) after hospitalization for a first NSTE-ACS. Thirty-three patients (22%) had acute coronary occlusion. These patients had impaired left ventricular function as ejection fraction was reduced (54.9 +/- 9.6 vs. 59.1 +/- 7.6%, P = 0.02). Regional myocardial function was assessed in a 16-segment model by two methods: longitudinal strain by speckle tracking echocardiography and wall motion score (WMS) by visual assessment. Patients with acute coronary occlusion had an increased number of adjacent dysfunctional segments. The median size of the dysfunctional area by strain was 7 [inter-quartile range (IQR) 4.5-9] vs. 2 (IQR 0-5) segments (P < 0.001). An area of >or=4 adjacent dysfunctional segments (strain greater than or equal to -14%) had the best ability to identify patients with acute coronary occlusion, with sensitivity 85% and specificity 70%. WMS demonstrated slightly less accuracy than strain.
Conclusion: Strain echocardiography identifies NSTE-ACS patients with acute coronary occlusion, who may benefit from urgent reperfusion therapy.