Early diastolic strain rate measurements by cardiac MRI in breast cancer patients treated with trastuzumab: a longitudinal study.

Abstract

We evaluated temporal changes in early diastolic strain rates by cardiovascular magnetic resonance (CMR) as an early detector of trastuzumab-induced ventricular dysfunction. We conducted a prospective, multi-centre, longitudinal observational study of 41 trastuzumab-treated breast cancer women who underwent serial CMR (baseline, 6, 12, and 18months). Two blinded readers independently measured left ventricular ejection fraction (LVEF), peak systolic strain parameters (global longitudinal strain [GLS] and global circumferential strain [GCS]), and early diastolic strain rate parameters (global longitudinal diastolic strain rate [GLSR-E], global circumferential diastolic strain rate [GCSR-E], and global radial diastolic strain rate [GRSR-E]), by feature tracking (FT-CMR) using CMR42. There was a significant decline in peak systolic strain GLS and GCS at 6months (p = 0.024 and p < 0.001, respectively) and 12months (p = 0.002 and p < 0.001, respectively), followed by recovery at 18months, which paralleled decline in LVEF at 6months (p = 0.034) and 12months (p = 0.012). Conversely, early diastolic strain rates GLSR-E and GCSR-E did not significantly change over 18months (p > 0.10), while GRSR-E was marginally significant at 12months (p = 0.021). There was no significant correlation between changes at 6months in LVEF and GLSR-E or GRSR-E (p > 0.10), and a marginally significant weak correlation between LVEF and GCSR-E (p = 0.046). Among trastuzumab-treated patients without overt cardiotoxicity, there was no consistent temporal change in FT-CMR-derived diastolic strain rate parameters up to 18months, in contrast to decline in systolic strain and LVEF. Systolic strains by FT-CMR are likely more useful than diastolic strain rates for monitoring subclinical trastuzumab-related myocardial dysfunction.ClinicalTrials.gov identifier NCT01022086.