Comparison of diaphragmatic breathing exercises and incentive spirometry on the functional status of heart failure patients: a randomized controlled trial.

Background: Respiratory muscle weakness in heart failure (HF) can deteriorate its symptoms such as fatigue, dyspnea, and impaired functional status. Pulmonary rehabilitation can strengthen these muscles. This study aimed to determine the impact of breathing exercises on fatigue severity, dyspnea, and functional classification in HF patients.

Methods: A three-arm single-blind randomized controlled trial was conducted on 90 hospitalized HF patients in three 30-participant groups including diaphragmatic breathing group (DG), incentive spirometry group (SG), and control group (CG). The interventions were performed thrice daily for 10 days in DG and SG. The Fatigue Severity Scale (FSS), Borg dyspnea scale, and New York Heart Association (NYHA) functional classification were used before and after the intervention. Data were analyzed using SPSS-20 software.

Results: After the intervention, the patients' frequency with severe fatigue decreased by 30% in both DG and SG (p < 0.001); the mean dyspnea score in DG and SG respectively reduced by 0.7 and 0.9 units at rest (p < 0.001) and reduced by 2.93 and 2.73 units during activity (p < 0.001); the total patients' frequency in functional class III and IV was significantly decreased by 30% in DG and 33.3% in SG (p < 0.001). The intervention groups were not significantly different regarding fatigue severity, dyspnea, and functional classification. While in CG these outcomes had no significant reduction after the intervention.

Conclusion: In this study breathing exercises could reduce fatigue and dyspnea, and improve NYHA functional classification of HF patients which can be included in nursing care plans for respiratory rehabilitation in HF.

Trial registration: This study was prospectively registered by the Iranian Registry of Clinical Trials ( https://irct.behdasht.gov.ir/ ) on 14/04/2024 with registration ID: IRCT20240306061197N.