Global, segmental, and layer-specific two-dimensional speckle tracking echocardiography immediately after acute myocardial infarction as a predictive tool to assess myocardial viability and scar size

Aim: The identification of myocardial scar is key in clinical decision-making after acute myocardial infarction (AMI). However, the gold standard that is cardiac magnetic resonance imaging (CMR) encounters limitations in terms of availability. Two-dimensional speckle tracking echocardiography (2D-STE) may be an accessible alternative in detecting scar and assessing scar transmurality. We aim to evaluate the predictive value of 2D-STE, encompassing measures of global, segmental and layer-specific strain, with respect to myocardial viability and scar size at 6 months follow-up.

Methods and results: In 43 patients admitted for primary AMI, we conducted a comparative analysis of strain parameters (including global longitudinal strain (GLS), segmental longitudinal strain (SLS), layer-specific GLS and SLS and the transmural strain gradient from endocardium to epicardium) in relation to conventional echocardiographic parameters at baseline in predicting for scar size and the transmurality index, as measured by CMR, 6 months post enrollment. We demonstrate a moderate correlation between both GLS and conventional echocardiographic parameters, and scar size as well as transmurality index. Wall motion score index exhibited superior predictive performance over GLS and left ventricular ejection fraction in anticipating scar formation. At a cut-off of - 13.3% for any scar and - 11.5% for transmural scar, SLS can predict scar formation. Layer-specific strain did not provide added predictive value.

Conclusion: SLS, but not layer-specific strain, during admission after AMI is an easy and accessible quantitative tool for predicting scar formation and transmurality extent at 6 months follow-up. GLS correlates well with scar size, suggesting its potential utility as a predictive tool.