Effects of different exercise programs on the cardiorespiratory reserve in HFpEF patients: a systematic review and meta-analysis.

HFpEF represents a heterogeneous syndrome with complex pathophysiological substrates and multiple clinical manifestations. Recently, much attention has been focused on cardiac rehabilitation programs for HFpEF patients, and several studies have examined the effects of exercise training on this specific population. This systematic review and meta-analysis included studies on adult patients with HFpEF and evaluated the impact of exercise on the cardiorespiratory fitness variables measured during CPET. The primary outcome was the difference in the change in the peak oxygen uptake (Δpeak VO2) between the groups. Literature search involved PubMed/MEDLINE, Cochrane/CENTRAL and Scopus databases. From an initial 5,143 literature records, we identified 18 studies fulfilling the inclusion criteria; 11 studies with 515 patients were finally included in the primary outcome analysis. Δpeak VO2 between baseline and study end was significantly higher in the groups of exercise training versus control (WMD 2.25 ml/kg/min, 95% CI 1.81-2.70). Exercise training resulted in greater change in the 6-minute walking test (6MWT) distance (WMD 2.25 m, 95% CI 1.81-2.70). Health-related quality of life (HRQoL) (WMD: -3.36, 95% CI -9.42 to 2.70, I2 = 14%, p = 0.33) and echocardiographic indices of diastolic function showed no differences between exercise and control groups at study end. In the subgroup analysis, no difference between resistance versus aerobic exercise was noted in Δpeak VO2, but high-intensity interval training showed a greater increase in peak VO2 versus aerobic exercise (WMD 1.62 ml/kg/min, 95% CI 0.96-2.29, I2 = 0%, p = 0.82). Exercise training in HFpEF results in significant improvements in peak VO2 and 6MWT distance as compared to those for controls. High-intensity interval training may offer greater enhancement of the exercise capacity of these patients than standard aerobic exercise.