Background: The role of left ventricular (LV) myocardial strain by cardiac magnetic resonance feature tracking (CMR-FT) for the prediction of adverse remodeling following ST-elevation myocardial infarction (STEMI), as well as its prognostic validity compared to LV ejection fraction (LVEF) and CMR infarct severity parameters, is unclear. This study aimed to evaluate the independent and incremental value of LV strain by CMR-FT for the prediction of adverse LV remodeling post-STEMI.
Methods: STEMI patients treated with primary percutaneous coronary intervention were enrolled in this prospective observational study. CMR core laboratory analysis was performed to assess LVEF, infarct pathology and LV myocardial strain. The primary endpoint was adverse remodeling, defined as ≥ 20% increase in LV end-diastolic volume from baseline to 4 months.
Results: From the 232 patients included, 38 (16.4%) reached the primary endpoint. Global longitudinal strain (GLS), global radial strain, and global circumferential strain were all predictive of adverse remodeling (p < 0.01 for all), but only GLS was an independent predictor of adverse remodeling (odds ratio: 1.36[1.03-1.78]; p = 0.028) after adjustment for strain parameters, LVEF and CMR markers of infarct severity. A GLS > - 14% was associated with a fourfold increase in the risk for LV remodeling (odds ratio: 4.16[1.56-11.13]; p = 0.005). Addition of GLS to a baseline model comprising LVEF, infarct size and microvascular obstruction resulted in net reclassification improvement of 0.26 ([0.13-0.38]; p < 0.001) and integrated discrimination improvement of 0.02 ([0.01-0.03]; p = 0.006).
Conclusions: In STEMI survivors, determination of GLS using CMR-FT provides important prognostic information for the development of adverse remodeling that is incremental to LVEF and CMR markers of infarct severity.
Clinical trial registration: NCT04113356.
Keywords: Cardiac magnetic resonance imaging; Left ventricular remodeling; Myocardial strain; ST-segment elevation myocardial infarction.