MRI-based prediction of adverse cardiac remodeling after murine myocardial infarction

Protti A, Dong X, Sirker A, Botnar R, Shah AM. MRI-based prediction of adverse cardiac remodeling after murine myocardial infarction. Am J Physiol Heart Circ Physiol 303: H309-H314, 2012. First published May 25, 2012; doi:10.1152/ajpheart.00208.2012.-Myocardial infarction (MI) results in adverse cardiac remodeling leading to heart failure and increased mortality. Experimental mouse models of MI are extensively used to identify mechanisms underlying adverse remodeling, but the extent of remodeling that occurs may be highly variable and can limit the utility to discover new disease pathways. The ability to predict the development of significant late post-MI remodeling would be invaluable in conducting such studies by increasing throughput and efficiency. This study aimed to identify potential thresholds of cardiac magnetic resonance imaging (MRI) parameters measured early after murine MI that would predict the development of significant adverse remodeling at 4 wk. MI was achieved by permanent coronary ligation and animals (n = 84) were followed up for 4 wk subsequently. MRI was used to assess left ventricular (LV) volumes, mass and ejection fraction, as well as infarct size (IS). Late gadolinium enhancement cine-MRI was performed at 2 days with standard cine-MRI at 30 days post-MI. Utilizing multiple logistic regression, we found that IS > 36%, at 2 days post-MI, was the overall best single predictor of adverse remodeling at 30 days (sensitivity 80.7%, specificity 88.9%; C-statistic of 0.939 from receiver-operating curve analysis). LV end-systolic volume (LVESV) > 32 mu l was also an excellent predictor comparable to IS. The combination of IS > 36% and/or LVESV > 32 mu l provided the highest predictive values for late adverse remodeling among multiple predictors. This study demonstrates that MRI-based estimation of IS and ESV during the acute phase of murine MI are good predictors of subsequent adverse remodeling that may aid experimental design.