Time Trends of Left Ventricular Ejection Fraction and Myocardial Deformation Indices in a Cohort of Women with Breast Cancer Treated with Anthracyclines, Taxanes, and Trastuzumab

Background: Trastuzumab, a HER2 monoclonal antibody, has transformed the prognosis of patients with the aggressive HER2-positive breast cancer type. Trastuzumab augments the cardiotoxic effects of anthracyclines, but its effect is thought to be at least partially reversible. The objective of this study was to examine the time trends of left ventricular (LV) size and function in a cohort of women treated with anthracyclines and trastuzumab. Methods: Twenty-nine patients >18 years of age with first-time breast cancer treated with anthracyclines and trastuzumab were monitored using echocardiography before, at the completion of, and at a median follow-up of 24.7 months (interquartile range, 15.9-34 months) after the end of their cancer treatment. LV volume, LV ejection fraction, and global peak systolic longitudinal strain and strain rate were measured in the apical four-and two chamber views. Left ventricular ejection fraction was measured using a modified Simpson's biplane method. Results: LV end-diastolic and end-systolic volumes increased at the end of treatment compared with baseline and did not recover during follow-up. Left ventricular ejection fraction, strain, and strain rate decreased at the end of treatment compared with baseline (from 64 +/- 6% to 59 +/- 8%, from -20.0 +/- 2.5% to -17.6 +/- 2.6%, and from -1.26 +/- 0.23 to -1.13 +/- 0.16 sec(-1), respectively; P < .05 for all parameters) and remained decreased at follow-up. Conclusions: LV dilation and subclinical impairment in cardiac function persists >2 years after the end of anthracycline and trastuzumab treatment, without significant recovery after trastuzumab cessation, suggestive of long-term underlying cardiac damage and remodeling.