Myocardial Strain as a Predictor of Acute Total/Subtotal Occlusion of Culprit Vessel in Patients with Non-ST Elevation Myocardial Infarction with Normal Left Ventricular Function

Abstract

Background: Acute total occlusion (ATO) of culprit vessel in patients with non ST elevation myocardial infarction (NSTEMI) accounts for a third of all NSTEMI patients. These patients have higher mortality and morbidity, hence earlier identification and appropriate interventions may improve their clinical outcomes. Aim: We attempted to identify such patients with newer echocardiographic parameters. We used global longitudinal strain (GLS) and regional myocardial strain to identify such patients in setting of normal echocardiograms. Methods: Single centre retrospective study that included all NSTEMI patients in 2018 who had angiographically proven acutely occluded culprit vessel with peri-procedure echocardiography. Results: 130 out of 321 NSTEMI patients who had angiograms in 2018 had ATO or sub-total culprit vessel occlusion. 71 patients either had left ventricular systolic dysfunction or had no echocardiogram performed immediately peri-procedure. 5 patients had poor images, unsuitable for strain analysis. 54 patients had good quality echocardiogram suitable for analysis. This was compared against 10 age and sex matched NSTEMI patients with near normal coronary arteries. Mean global longitudinal strain was 14 ± 3 as compared to 18 ± 1 in patients with normal coronaries. Regional strain abnormality correlated well in 96% of cases with culprit vessel occlusion. In one patient it was falsely positive and the other had abnormal GLS but did not localise the culprit vessel. Conclusion: GLS and regional myocardial strain can identify patients with NSTEMI who have acutely occluded culprit vessel and may enhance their targeted therapy. Prospective registry and randomised studies are necessary to prove the same.