Protective effects of exercise on cardiotoxicity induced by breast cancer treatments: A systematic review and meta-analysis

Objective: Currently, one of the main causes of death in women with breast cancer is cardiovascular disease caused by the oncologic therapies. Exercise has demonstrated positive effects on cardiovascular fitness in individuals without cancer. Therefore, the aim of this study was to evaluate the cardioprotective effects of exercise in women with breast cancer, during and after the application of their treatments. Methods: Systematic search was done in PubMed, Scopus, Web of Science, CINAHL, MEDLINE, SPORTDiscus, and PEDro. The articles must have been published in the last ten years; the intervention to be evaluated was to consist of an exercise program; the sample had to comprise women who were undergoing breast cancer treatment or who had completed it at the time of the intervention; and the outcome variables had to include at least one parameter for the assessment of cardiac function and/or structure. Results: Of the 28 articles identified, nine reported non-randomized controlled studies, 16 randomized clinical trials and three quasi-experimental studies. The effects of exercise on left ventricular ejection fraction, global longitudinal strain and the E/A waveforms ratio were not significant. However, its effect on VO2max was significant. Conclusions: Exercise does not seem to be effective in avoiding the cardiotoxic effects of oncological treatment for breast cancer. Although exercise seems to mitigate the symptomatology, reflected in improved functional capacity, more long-term studies are needed. PROSPERO registration code: CRD42023391441