EVALUATION OF LEFT VENTRICULAR SYSTOLIC FUNCTION IN POSTMENOPAUSAL WOMEN WITH BREAST CANCER RECEIVING ADJUVANT ANTHRACYCLINE AND TRASTUZUMAB THERAPY: A 2-YEAR FOLLOW-UP STUDY.

Anti-cancer therapy with anthracyclines and trastuzumab has raised concerns regarding cancer therapy-related cardiac dysfunction (CTRCD) in breast cancer (BC) patients. This study aimed to assess left ventricular (LV) ultrasound parameters in BC postmenopausal women during a 2-year follow-up period after starting anti-cancer therapy.

Methods: We studied 74 women with early-stage BC with, a mean age of 62.3 (SD-8.6), who underwent adjuvant doxorubicin or doxorubicin + trastuzumab therapy. Parameters such as LV ejection fraction (LVEF), global longitudinal strain (LVGLS), and mitral annulus systolic velocity(S') were evaluated. Serial evaluations were conducted at baseline(T0) and the first (T1), second (T2), third (T3), sixth (T4), ninth (T5), twelfth (T6), and twenty-fourth month (T7) following the initiation of the chemotherapy. Cardioprotective therapy (CPT) was administered to high-risk patients and those with worsening LV systolic parameters. A multiple regression model was employed to assess the combined effects of various factors and co-factors on the outcome variables. Cardiotoxicity was evaluated using the survival analysis tools (Kaplan-Meier curves and Cox proportional model).

Results: A total of 27 (36.5%) patients developed CTRCD, although no patients were presented with symptomatic heart failure. LVGLS started to decline one month after the first anthracycline dose (T1) in 13.5% of the cohort and 34.5% of patients with CTRCD (p<0.000). From the third month, 10.8% of the patients showed a decrease in EF%, including 27.6% of patients with CTRCD in (P<0.000). Throughout, the study, S' remained within the normal range in patients without CTRCD, only patients with CTRCD showed a decline in S'.

Conclusions: This prospective study revealed that:1) The dynamic assessment of GLS should be prioritized for the early detection of systolic dysfunction .2) S' possesses a high diagnostic value for identifying cardiotoxicity. 3) Implementing the optimal medical cardioprotective strategies and closely monitoring LV systolic function can prevent serious cardiac complications in patients undergoing highly cardiotoxic anti-cancer treatment.