Abstract 14721: Association of Cardiorespiratory Fitness with Non-invasive Measures of Arterial and Ventricular Stiffness: The Dallas Heart Study
Introduction: Low fitness (CRF) is associated with a greater risk for heart failure with preserved ejection fraction (HFPEF) through mechanisms that are not well understood. Because of the established contribution of arterial and ventricular stiffness in the pathophysiology of HFPEF, we evaluated the association between CRF and indices of ventricular-arterial mechanics.
Methods: We studied Dallas Heart Study-II participants without cardiovascular disease who had CRF estimated as the peak oxygen uptake from a submaximal treadmill test using the Givoni’s equation and Hellerstein’s formula. The participants also had ECG-gated cine cardiac MRI imaging using 3-T MRI system. Ventricular stiffness (end-systolic elastance, Ees) was defined as the ratio of end-systolic BP [EBP = 0.9 X Systolic BP (SBP)] to end systolic volume (ESV), and arterial stiffness (effective arterial elastance, Ea) was defined as the ratio of EBP to stroke volume (SV). Associations of CRF with Ea and Ees among normotensive (SBP <120), pre-hypertensive (SBP = 120-140) and hypertensive participants (SBP > 140) were evaluated using multivariable-adjusted linear regression analysis.
Results: A total of 1,687 participants (58% women) were included in the analysis. On univariate analysis, CRF was directly associated with SV (R= 0.3; P<0.01) and ESV(R= 0.3; P<0.01). Also, lower CRF was associated with higher Ea and Ees among men across all age groups, and older women (age >55). After multivariable adjustment, CRF was inversely associated with Ea and Ees among normotensive, pre-hypertensive and hypertensive participants (Table). Furthermore, age, female sex and low body mass index were each associated with greater Ea and Ees among the study participants.
Conclusion: Low fitness is associated with greater arterial and ventricular stiffness among normotensive as well as hypertensive participants. This association reflects fitness related differences in stroke volume and ventricular dimensions.
Author Disclosures: A. Pandey: None. C. Ayers: None. S. Shah: None. S. Das: None. M. Drazner: None. B. Levine: None. J. De Lemos: None. R. Peshock: None. J. Berry: None.
- © 2014 by American Heart Association, Inc.