P1533 Early evaluation of global longitudinal strain and biomarkers at initiation of trastuzumab treatment in breast cancer patients

Abstract

Abstract Funding Acknowledgements The Danish Heart Foundation, Copenhagen (grant number: 14-R97-A5188-22839 and 15-R99-A5940). The Research Fond of the Region of Southern Denmark. Background Global longitudinal strain (GLS) is recommended to detect subclinical changes preceding reduced left ventricular ejection fraction (LVEF) in trastuzumab related cardiotoxicity. The possibility to detect signs of acute myocardial deterioration at treatment initiation is not thoroughly investigated. Accordingly, the aim of this study was to assess changes in GLS and biomarkers within the first two weeks of trastuzumab treatment. Methods In a prospective cohort study 45 patients with non-metastatic breast cancer (age 54, LVEF 62.8% (SD ± 3.6), GLS -19.9% (SD ± 2.1), 40% hypertension) were included. Examinations including echocardiography and measurement of troponin T and NT-proBrain Natriuretic Peptide were conducted before initiation of trastuzumab, at day 3, 7 and 14 and after 3, 6 and 9 months. Results A significant deterioration in LVEF, GLS, s’, e’ septal and s’RV occurred during the 9 months study period and was proceed by significant changes in all these parameters within the first 14 days. After 14 days 12 patients (27%) had an increase in GLS ≥10 %, which was associated with significantly lower LVEF at nine month at 55.2% (SD ± 4.1) vs. 59.5% (SD ± 3.5) (p = 0.001) compared to patients with <10 % early increase in GLS (Figure 1). No difference in plasma concentrations of cardiac biomarkers was observed between the two groups. Conclusion In this cohort study deteriorations in key echocardiographic parameters were detected within the first two weeks of trastuzumab treatment, and an early 10 % increase in GLS was associated with a lower LVEF at nine months. Abstract P1533 Figure 1