Song L, et al. - Researchers assessed temporal changes in left ventricular (LV) diastolic filling relative to other LV parameters with cardiac MRI (CMR) in 41 patients with HER2 positive breast cancer receiving trastuzumab therapy. These patients displayed significant subclinical harmful effects in both LV systolic and diastolic function. Following end of therapy at 18 months, recovery in LV systolic function occurred but reduction in diastolic function as measured by LV peak filling rate corrected for end-diastolic volume endured. This suggests a possible value of diastolic dysfunction as a marker of trastuzumab-induced cardiotoxicity that needs to be confirmed in a larger study.