Individualized paced deep breathing training with autonomic nervous function as rehab targets in patients with chronic heart failure: a randomized clinical trial

Background: The autonomic imbalance and low vagal tone are common characteristic among patients with chronic heart failure (CHF). It is hypothesized that CHF rehabilitation programs targeting autonomic nerves system (ANS) function may offer greater efficacy for CHF management. This trial represents the first attempt to investigate such an approach. Methods: This is a randomized controlled trial aimed to examine the effectiveness of individualized paced deep breathing training (IBT) in CHF patients, with ANS measures as rehabilitation targets. Patients in the IBT group received an additional 4-week program of IBT alongside their standard rehabilitation care. The cardiopulmonary resonance index (CRI), 6-Minute Walking Distance (6MWD) and the Minnesota Quality of Life Score Questionnaire (MLHFQ) were assessed at baseline (T1) and after 4 weeks (T2). Results: All 38 participants completed the trial successfully. Participants in the IBT group showed significant improvements in CRI, including enhancements in respiratory stability (RS), cardiopulmonary resonance amplitude (CRA), cardiopulmonary resonance factor (CRF), cardiopulmonary coupling coefficient (CPC), and the Spearman's Rank Correlation Coefficient between Respiratory Rate and Heart Rate (CRS). Further, improvements in both 6MWD and MLHFQ scores were observed. [Multiple linear regression analysis results showed correlations between RS and white blood cell (r = 0.924), CRF and procalcitonin (r = 0.733) and serum creatinine (r = 0.494), as well as CRS and glycosylated hemoglobin (r = 0.819)]. Conclusions: These findings demonstrate that IBT is a feasible and effective rehabilitation approach for CHF patients with ANS measures as target. The IBT program here also showed therapist efficiency and good patients compliance.