HIGHLIGHTED TOPIC Exploring New Concepts in the Management of Heart Failure with Preserved Ejection Fraction: Is Exercise the Key for Improving Treatment? High-intensity interval training vs. moderate-intensity continuous exercise training in heart failure with preserved ejection fraction: a pilot study

Angadi SS, Mookadam F, Lee CD, Tucker WJ, Haykowsky MJ, Gaesser GA. High-intensity interval training vs. moderate-intensity continuous exercise training in heart failure with preserved ejection fraction: a pilot study. J Appl Physiol 119: 753–758, 2015. First published September 4, 2014; doi:10.1152/japplphysiol.00518.2014.—Heart failure with preserved ejection fraction (HFpEF) is a major cause of morbidity and mortality. Exercise training is an established adjuvant therapy in heart failure; however, the effects of high-intensity interval training (HIIT) in HFpEF are unknown. We compared the effects of HIIT vs. moderate-intensity aerobic continuous training (MI-ACT) on peak oxygen uptake (V̇O2peak), left ventricular diastolic dysfunction, and endothelial function in patients with HFpEF. Nineteen patients with HFpEF (age 70 8.3 yr) were randomized to either HIIT (4 4 min at 85-90% peak heart rate, with 3 min active recovery) or MI-ACT (30 min at 70% peak heart rate). Fifteen patients completed exercise training (HIIT: n 9; MI-ACT: n 6). Patients trained 3 days/wk for 4 wk. Before and after training patients underwent a treadmill test for V̇O2peak determination, 2D-echocardiography for assessment of left ventricular diastolic dysfunction, and brachial artery flow-mediated dilation (FMD) for assessment of endothelial function. HIIT improved V̇O2peak (pre 19.2 5.2 ml·kg ·min ; post 21.0 5.2 ml·kg ·min ; P 0.04) and left ventricular diastolic dysfunction grade (pre 2.1 0.3; post 1.3 0.7; P 0.02), but FMD was unchanged (pre 6.9 3.7%; post 7.0 4.2%). No changes were observed following MI-ACT. A trend for reduced left atrial volume index was observed following HIIT compared with MI-ACT ( 3.3 6.6 vs. 5.8 10.7 ml/m; P 0.06). In HFpEF patients 4 wk of HIIT significantly improved V̇O2peak and left ventricular diastolic dysfunction. HIIT may provide a more robust stimulus than MI-ACT for early exercise training adaptations in HFpEF.