Trastuzumab-induced cardiotoxicity: the role of two-dimensional myocardial strain imaging in diagnosis and management.

A 45-year-old female breast cancer patient developed heart failure during adjuvant trastuzumab therapy. Her initial left ventricular ejection fraction (LVEF) was 39% and corresponding global longitudinal and circumferential systolic strain measurements were also significantly reduced. Trastuzumab was ceased and supportive cardiac therapy commenced. The ensuing LVEF and systolic strain measurements showed consistent improvement so that trastuzumab was recommenced (while supportive cardiac therapy continued). At this point, reduced circumferential systolic strain with preserved LVEF was observed. Subsequent echocardiograms revealed further reductions in circumferential and longitudinal systolic strain without reductions in LVEF.