Synergistic effects of combined breathing training and aerobic exercise on cardiopulmonary function in chronic heart failure: a systematic review and meta-analysis

Background Chronic heart failure is a complex clinical syndrome that poses a serious threat to human health. Breathing training and aerobic exercise are key strategies for promoting rehabilitation in these patients. The present study aimed to investigate the effects of breathing training combined with aerobic exercise on cardiopulmonary function and quality of life in patients with chronic heart failure. Methods A computer-based search was conducted using a combination of subject terms and free-text terms to identify randomized controlled trials evaluating the effects of breathing training combined with aerobic exercise on cardiopulmonary function in patients with chronic heart failure from both Chinese and international databases. All databases were searched from inception to April 2025. Two reviewers independently screened studies, extracted data, and assessed the risk of bias. Meta-analyses were performed using RevMan 5.4 and Stata 17.0. Results A total of seven randomized controlled trials involving 246 patients were included. The analysis showed that, compared with the control group, breathing training combined with aerobic exercise resulted in statistically significant improvements across several functional outcomes, including exercise duration (SMD = 0.32, 95% CI 0.05 to 0.60, p = 0.02) and quality of life (SMD = −1.09, 95% CI −1.78 to −0.40, p < 0.001). No significant effects were observed on cardiac function parameters. Subgroup analyses suggested that factors such as sex composition may influence intervention effects, and sensitivity analyses confirmed the robustness of these findings. Conclusion Breathing training combined with aerobic exercise has positive effects on pulmonary function, cardiopulmonary exercise capacity, and quality of life in patients with chronic heart failure, while its impact on cardiac function parameters appears to be limited. Given the limited number and quality of the included studies, these conclusions and the optimal intervention duration require further confirmation in high-quality research. This study has completed registration with the Systematic Review Program at PROSPERO under registration number CRD420251014242.