Strain predicts left ventricular functional recovery after acute myocardial infarction with systolic dysfunction

Objective: Regional and global longitudinal strain (RLS-GLS) are considered reliable indexes of myocardial viability in chronic ischemic patients and prediction of left ventricular (LV) functional recovery after acute myocardial infarction (MI) with preserved left ventricular ejection fraction (LVEF). We tested in the present study whether RLS and GLS could also identify transmural extent of myocardial scar and predict LV functional recovery and remodeling in patients with reduced LVEF after acute MI.

Methods: Echocardiography and late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) were performed in 71 patients with reduced LVEF (≤45%) after acute MI treated with acute percutaneous coronary intervention. At 8-month follow-up, echocardiography was repeated to determine global LV functional recovery and remodeling.

Results: RLS was worse in transmural than in non-transmural infarcted segments (-6.6 ± 6.1% vs -10.3 ± 5.9%, p < 0.0001) and in non-transmural than in normal segments (-10.3 ± 5.9% vs -14.5 ± 6.4%, p < 0.0001). RLS > -12% had sensitivity of 78% and specificity of 69% to identify transmural infarcted segments (AUC = 0.79; 95% CI, 0.77-0.81, p < 0.0001). GLS > -11.3% had sensitivity of 53% and specificity of 100% to predict the absence of LV global functional improvement (AUC = 0.73, CI, 0.55-0.87, p = 0.01) at 8-month follow-up. GLS < -12.5% predicted the absence of adverse LV remodeling with sensitivity of 100% and specificity of 54% (AUC = 0.83; CI, 0.66-0.94, p < 0.0001). GLS > -11.5% was associated with a poor prognosis.

Conclusions: In patients with reduced LVEF after acute MI, RLS and GLS allow: (1) identification of transmural extent of myocardial scar and (2) predict LV global functional recovery and remodeling at 8-month follow-up.