Effects of Cardiac Resynchronization Therapy on a Six-minute Walk Test, Maximal Inspiratory Pressure and Peak Expiratory Flow in Patients with Heart Failure: A Longitudinal Study

Background: Cardiac resynchronization therapy (CRT) is an effective treatment for patients with heart failure. Objective: To evaluate the response of CRT in maximal inspiratory pressure (MIP), peak expiratory flow (PEF), and exercise tolerance as determined by the six-minute walk test (6MWT) in patients with HF. Methods: This study used the 6MWT and Manovacuometer to assess functional capacity in relation to activities of daily living, in which fatigue and dyspnea are common. Results: After six months of CRT, this study identified improvements in the 6MWT, p<0.05; MIP, p=0.01; and PEF, p=0.03. Conclusion: After CRT, this study showed a significant improvement in MIP, PEF, and exercise tolerance. However, further studies are warranted to demonstrate the relevance of these findings.