Monitoring of anthracycline-induced myocardial injury using serial cardiac magnetic resonance: An animal study.

PURPOSE To assess the feasibility of using comprehensive serial cardiovascular MR (CMR) to evaluate bilateral ventricle mechanical changes and myocardial tissue characteristics, as well as correlations between the serial CMR and histology in a beagle model of anthracycline-induced cardiotoxicity. METHODS This animal study was approved by the institutional review board. Serial CMR imaging was performed in a total of fifteen beagles at baseline (n = 15), at week 16 (n = 10) and week 24 (n = 7) post-anthracycline. Feature-tracking CMR (FT-CMR) was applied to measure bilateral ventricular (left ventricle (LV) and right ventricle (RV)) global peak strain including radial (GRS), circumferential (GCS) and longitudinal (GLS) strain. The changes in strain, LV/RV functional parameters, native T1, extracellular volume fraction (ECV) and collagen volume fraction (CVF) were calculated. RESULTS Compared to baseline at weeks 16 and 24, significantly decreases to LV-GLS and native T1 were observed, while ECV significantly increased (all P < 0.05). LVEF significantly decreased and LV-EDV/ESV significantly increased at week 16 compared to baseline (all P < 0.05), but no further progression was seen at week 24. RV-GLS significantly decreased at week 16, but no further progression was seen at week 24, while RVEF was different until week 24. CVF increased significantly during modeling. Native T1 and ECV showed positive correlation with CVF (r = 0.645, P < 0.001), while LV-GLS showed negative correlation with CVF (r = -0.736, P < 0.05). CONCLUSION Cardiotoxicity affects the RV slightly and less progressively than the LV. FT-CMR-based GLS, native T1 and ECV may potentially be used as imaging biomarkers for early monitoring of anthracycline-induced myocardial Injury.