Inspiratory muscle training improves cardiopulmonary function in patients after transcatheter aortic valve replacement: a randomized clinical trial

Aims Inspiratory muscle training (IMT) can increase the strength or endurance of the diaphragm and accessory muscles of inspiration, yet there is no evidence that endorses the role of IMT in patients of transcatheter aortic valve replacement (TAVR). This study for the first time tested the effects of IMT plus usual cardiac rehabilitation (CR) function in patients after TAVR. Methods and results A double-blinded, randomized controlled, single-centre clinical trial was undertaken. Participants who had a confirmed diagnosis of valve heart disease and were clinically stable after TAVR were recruited and received a CR programme during the hospital stay. A total of 96 patients were recruited and randomly assigned to the IMT + CR group (n = 48) or the CR group (n = 48) in a 1:1 ratio. The group difference in the primary outcome, the 6-min walk distance at the discharge of the hospital, significantly favoured the IMT + CR group (mean difference -33.52, 95% CI: -64.42 to -2.62, P = 0.034). The significant difference was maintained at the 1-month and 3-month follow-ups (mean difference: 41.51, 95% CI: 1.82-81.21, P = 0.041). In addition, the mean hospital stays of subjects in the IMT + CR group was 11 days, which was significantly shorter than the 12.5 days in the CR group (P = 0.016). Sensitivity analysis using per-protocol analysis supported these findings. No adverse treatment-related events were reported. Conclusion Compared with usual CR, IMT plus CR can effectively improve exercise endurance, pulmonary ventilation function, and inspiratory muscle strength in patients after TAVR and shorten the length of hospital stay.