Diagnostic and prognostic value of 2D-Strain in Non-ST Elevation Myocardial Infarction.

Background: Strain has shown a promising diagnostic and prognostic value in acute coronary syndromes. With, however, less data in non-ST elevation myocardial infarction (NSEMI).

Aim: to evaluate in NSTEMI patients, the ability of strain to predict the severity of the disease, by assessing correlations to established prognostic parameters, and to predict culprit and occluded coronary arteries (CA). Secondary, to determine factors associated to strain changes during follow-up.

Methods: The study was prospective, NSTEMI patients with significant coronary lesion and without significant non-ischaemic disease were included. Angiographic and echocardiographic investigation including global (GLS) and territorial (TLS) longitudinal strain were performed within 24h from admission. Syntax I score was calculated. Severe coronary artery disease (CAD) was defined by left main of three-vessel disease.

Results: Seventy NSTEMI patients aged 60.2±10.1 years were enrolled; 61% were smokers, 54% diabetics and 46% hypertensive. 34% had a severe CAD, 7% had an acute coronary occlusion (ACO) and 14% a chronic coronary total occlusion (CTO). GLS >-15.3% predicted a left ventricular ejection fraction (LVEF) <50% with 80% Sensitivity (Se) and 78% Specificity (Sp). GLS was associated to CAD complexity and severity. GLS > -14.1% detected severe CAD with 83% Se and 80%Sp. TLS determined the culprit artery in 74% of cases and TLS > -9.2% predicted ACO with 85% Se and 85% Sp. TLS was also associated to CTO. At a 10 months median follow-up [3-12months], GLS significantly improved, baseline LVEF, GLS, wall motion score index and revascularization were the predictors of this improvement.

Conclusion: In NSTEMI patients, GLS detected severe CAD and poor myocardial function. TLS predicted the culprit vessel and its occlusion. GLS improvement at midterm was predicted by baseline systolic LV function parameters and myocardial revascularization.