Role of myocardial deformation analysis in the early detection of subclinical Left Ventricular dysfunction in breast cancer under anthracyclines and trastuzumab

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Introduction : Cardio-oncology field has notably raised interest this past decade, it considerably improved cancer patients’ quality of care by monitoring and preventing complications of cardiotoxic treatment like anthracyclines and trastuzumab. Transthoracic echocardiography (TEE) plays a major role in the baseline assessment and follow-up of cardio-oncology patients. While left ventricular ejection fraction (LVEF) still has its place in cardiac monitoring, new modalities like myocardial deformation imaging with speckle tracking strain analysis, show great potential for early detection of subclinical LV dysfunction. Purpose : The aim of this study was to evaluate the role of Global Longitudinal Strain (GLS) in the early detection of cardiotoxicity and its correlation to LVEF. Methods : We conducted a longitudinal prospective study including all the breast cancer patients treated with anthracyclines and/or trastuzumab followed in the Casablanca cardio-oncology unit from January 2017 to December 2019. All patients underwent baseline TEE, and were followed-up every 3 months after that, with GLS assessment whenever it was possible. We evaluated the frequency of GLS drop and its correlation to LVEF reduction. Results : Out of a total of 793 patients, 677 had available LV GLS assessment. Among them, 83 (12,3%) decreased their GLS during follow-up, 67% of which had no concomitant drop in LVEF. In these patients, impaired LV GLS values were noted at 1 month after chemotherapy and at 3, 6, and 12 months compared with baseline (-22,3 ± 1.8% at baseline, -18.1 ± 2.3% at 1 month, -17.7 ± 2.1% at 3 months, -17.1 ± 2.2% at 6 months, and -16.9 ± 2.1% at 12 months (p < 0,0001). LV GLS at 3 months was strongly correlated to cardiotoxicity (LVEF < 50%) at 12 months (p < 0,0001). A cut-off LV GLS value of -17,7% was then retained to identify LVEF alteration at the end of follow-up. Moreover, lower GLS values were observed in patients under Doxorubicin with a mean cumulative dose >180 mg/m2 (p = 0,0019), while LVEF remained normal. Finally, our study found that GLS at 1 month and 3 months had a prognostic value, since the lower GLS was, the poorest the patient’s clinical outcome was, with further development of symptomatic heart failure (p = 0,0038). Conclusion : Our study demonstrates that myocardial deformation analysis enables detection of early and progressive subclinical cardiac dysfunction, and GLS at 3 month was positively correlated to LVEF drop at 12 months. Thus, routine GLS should be used in patients undergoing cardiotoxic chemotherapy in order to early detect cardiotoxicity and prevent irreversible cardiac dysfunction by early initiating cardio-protective treatment.