Effects of exercise on cardiac function outcomes in women receiving anthracycline or trastuzumab treatment for breast cancer: a systematic review and meta-analysis

Background: we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the efficacy of exercise training on cardiac function and circulating biomarkers outcomes among women with breast cancer (BC) receiving anthracycline or trastuzumabcontaining therapy. Methods: PubMed, EMBASE, Cochrane Library, Web of Science and Scopus were searched. The primary outcome was change on left ventricular ejection fraction (LVEF). Secondary outcomes included diastolic function, strain imaging and circulating biomarkers. Results: Four RCTs were included, of those three were conducted during anthracycline and one during trastuzumab, involving 161 patients. All trials provided absolute change in LVEF (%) after a short to medium-term of treatment exposure (≤6 months). Pooled data revealed no differences in LVEF in the exercise group versus control [mean difference (MD): 2.07%; 95% CI: −0.17 to 4.34]. Similar results were observed by pooling data from the three RCTs conducted during anthracycline. Data from trials that implemented interventions with ≥36 exercise sessions (n = 3) showed a significant effect in preventing LVEF decline favoring the exercise (MD: 3.25%; 95% CI: 1.20 to 5.31). No significant changes were observed on secondary outcomes. Conclusions: exercise appears to have a beneficial effect in mitigating LVEF decline and this effect was significant for interventions with ≥36 exercise sessions.publishe