Structured exercise and cardiac outcomes during anthracycline or anti-HER2 therapy in breast cancer: systematic review and meta-analysis of randomized trials.

purposeTo evaluate whether structured exercise, compared with usual care, preserves left ventricular ejection fraction (LVEF), global longitudinal strain (GLS), and cardiac biomarkers in women with breast cancer receiving anthracyclines and/or anti-HER2 therapy.

methodsWe performed a systematic review and meta-analysis of randomized controlled trials. Risk of bias was assessed with the revised Cochrane risk-of-bias tool for randomized trials (RoB 2), and certainty of evidence with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. When clinically and methodologically comparable, effects were pooled as net differences in change (ΔEG - ΔCG) using random-effects models. The primary synthesis was restricted to the baseline-to-end-of-anthracycline-treatment window (~ 4 months).

resultsSeven trials (9 reports; n = 513) were included. Most trials had some concerns or high risk of bias. Quantitative synthesis was feasible in only two trials. No between-group differences were observed for LVEF (MD 0.07, 95% CI - 1.38 to 1.52; I

conclusionCurrent randomized evidence is sparse, heterogeneous, and of low certainty. Available data do not confirm a consistent cardioprotective effect of exercise on LVEF or GLS and do not permit conclusions about clinical cardiovascular events, survival, or HFpEF.