Effectiveness and safety of exercise training and rehabilitation in pulmonary hypertension: a systematic review and meta-analysis

Pulmonary hypertension (PH) is a chronic progressive disease characterized by increasing pulmonary vascular resistance, poor prognosis and high disability rate. Although many targeted drugs for PH have been put to clinical use, most patients still have poor exercise tolerance and quality of life. Exercise training is considered to further improve exercise capacity and quality of life in patients with PH, but it has not been fully studied and utilized. The aim of this systematic review and meta-analysis is to evaluate the effectiveness and safety of exercise training in patients with PH.A search was conducted for the meta-analysis using the databases PubMed, Embase, Cochrane Library, including literature published before December 2018. The primary outcome of this meta-analysis was a change in the 6-minute walk distance (6MWD). In addition, peak oxygen uptake (PeakVO2), resting pulmonary arterial systolic pressure (PASPrest), resting heart rate (HRrest), peak exercise heart rate (HRpeak), oxygen uptake anaerobic threshold (VO2 at AT), maximum workload and quality of life (QoL) were also assessed.A total of 651 patients in 17 studies were included. A meta-analysis showed that exercise training was associated with significant improvement in the 6MWD [weighted mean difference (WMD): 64.75 m (95% CI: 53.19-76.31 m, P<0.001)], peakVO2 [WMD: 1.78 mL/min/kg (95% CI: 1.27-2.29 mL/min/kg, P<0.001)], HRpeak [WMD: 11.07 beats/min (95% CI: 8.04-14.11 beats/min, P<0.001)] and QoL measured by SF-36 questionnaire subscale scores. Furthermore, exercise training is well tolerated, and no major adverse event occurred related to exercise training.Exercise training is associated with a significant improvement in exercise capacity, cardiorespiratory fitness and quality of life among patients with PH and proved to be safe for stable PH patients with optimization of medical therapy. However, more large-scale multicenter studies are needed to confirm the effectiveness and safety of exercise training in patients with PH.