Reversing the Cardiac Effects of Sedentary Aging in Middle Age-A Randomized Controlled Trial: Implications For Heart Failure Prevention.
Level 2 - randomized trial
Prospective parallel-group randomized controlled trial
PubMed 29311053 · doi:10.1161/CIRCULATIONAHA.117.030617
What was done
Sixty-one healthy, sedentary middle-aged adults (mean age 53±5 years; 48% male) were randomized to 2 years of supervised exercise training (n=34) or an attention control group (n=27). Participants underwent right heart catheterization and 3-dimensional echocardiography with preload manipulations to evaluate left ventricular end-diastolic pressure-volume curves and calculate left ventricular stiffness constants, alongside testing for maximal oxygen uptake (VO2 max).
What was found
Fifty-three participants completed the trial with 88±11% adherence. VO2 max increased by 18% in the exercise group (29.0±4.8 to 34.4±6.4) versus control (29.5±5.3 to 28.7±5.4; group×time P < 0.001). Left ventricular stiffness constant decreased with exercise from 0.072±0.037 to 0.051±0.0268 (P = 0.0018) but was unchanged in controls (0.0635±0.026 to 0.062±0.031, P = 0.83; group×time P < 0.001). Exercise also increased left ventricular end-diastolic volume (group×time P < 0.001) while pulmonary capillary wedge pressure was unchanged, providing greater stroke volume for any given filling pressure (loading×group×time P = 0.007).
Why it matters
This demonstrates that age- and sedentary-related left ventricular stiffening is reversible in middle age through prolonged exercise training, providing a physiological mechanism for preventing heart failure with preserved ejection fraction.
Limits
The study had a small sample size (61 randomized, 53 completed) and evaluated healthy middle-aged participants, which may limit generalizability to older or comorbid populations. Long-term incidence of clinical heart failure was not measured.