Abstract 15520: High Intensity Exercise Training Improves Ventricular-Arterial Coupling
Introduction: The “dynamic” Starling mechanism, reflecting time-varying ventricular-arterial coupling, is impaired with sedentary aging. The impaired ventricular-arterial coupling may impact cardiac energetics, and increase the risk of developing HFpEF.
Hypothesis: We tested the hypothesis that 2-years of high-intensity exercise training would preserve the dynamic Starling mechanism compared with sedentary controls.
Methods: Sixty-one (Male: 48%) healthy middle-aged participants were randomized to 2-years of high-intensity exercise training or control/yoga. Right heart catheterization and model-flow analysis of the arterial pressure waveform was performed during controlled breathing at 0.2 Hz, before and at 2-years follow-up. The dynamic Starling mechanism was estimated by transfer function gain between beat-by-beat changes in diastolic pulmonary artery pressure (PAD), a surrogate for LVEDP, and SV-index.
Results: Fifty-three participants completed the 2-year study (ExT group: n=28, 53±4 yrs vs. Controls: n=25, 52±6 yrs). The dynamic Starling mechanism gain was significantly improved in ExT group while Controls was not (Figure). Exercise training also improved the spectral power density (PSD) of PAD, the input variable of the dynamic Starling mechanism, without a change in Controls (Group*Time interaction, P=0.025, ExT group: from 1.21±0.16 to 0.75±0.16, P=0.006 vs. Controls: from 1.19±0.17 to 1.12±0.17 mmHg2, P=0.99). In contrast, there were no statistically significant effects on SV-index (P=0.69). There was no difference in the coherence which confirms the reliability of the linear transfer function among the 2-groups (P=0.63).
Conclusions: Two years of high-intensity exercise training improved dynamic ventricular-arterial coupling and PSD of PAD which suggests greater LV distensibility. These findings may be one mechanism by which exercise training may prevent age-related increases in cardiac stiffness.
Author Disclosures: M. Hieda: None. S. Sarma: None. E. Howden: None. T. Tarumi: None. Q. Fu: None. R. Zhang: None. B. Levine: None.
- © 2017 by American Heart Association, Inc.