Abstract 15176: Incremental Utility of Echocardiographic Strain for Assessment of Myocardial Infarct Size and Thrombus as Assessed via Cardiac Magnetic Resonance Tissue Characterization

Background: Myocardial strain provides a novel means of quantifying subtle alterations in LV function; utility of strain as a marker of MI size and stratification index for post MI thrombus (LVT) is unknown. Methods: Anterior ST elevation MI pts were enrolled; CMR, echo and ECG were done 4 weeks post MI (99% same day): Delayed enhancement (DE) CMR was the reference for MI and LVT; cine CMR volumetrically quantified global EF and regional EF in pre-specified LV landmarks. Echo EF and speckle tracking regional and global longitudinal strain (GLS) were measured independently. Results: 74 pts prospectively underwent echo and CMR 28±7 days post MI. Echo GLS correlated with CMR MI size (r=0.66, p<0.001), MI size based on peak CPK (r=0.52, p<0.001) and ECG Q wave area (r=0.44, p=0.001). GLS decreased stepwise vs CMR MI size and was 1.9-fold higher among patients in the highest vs lowest MI quartile (17.9±3.3 vs 9.3±2.5; p<0.001): Use of an established cutoff (17%) showed pts with impaired GLS to have more prolon...