Abstract 19981: Relationship of Cardiorespiratory Fitness and Adiposity With Left Ventricular Peak Systolic Strain in Middle-age Adults: The Dallas Heart Study
Introduction: Low cardiorespiratory fitness (CRF) and obesity are associated with an increased risk for heart failure (HF). However, the mechanisms through which CRF and adiposity might increase HF risk are not fully understood. Because impaired left ventricular (LV) peak systolic strain is an early subclinical marker of HF, we evaluated the association of CRF and adiposity with LV peak systolic strain.
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 and total body fat measured by dual x-ray absorptiometry. The participants also had ECG-gated tissue-tagged cardiac MRI imaging using 3-T MRI. Peak mid-wall systolic circumferential strain (Ecc) was determined by harmonic phase imaging. Associations of CRF and measures of overall adiposity [percent body fat (%BF)] and visceral adiposity [waist circumference (WC)] with Ecc were determined using multivariable adjusted linear regression analysis.
Results: A total of 1,493 participants (57% women, 42% African Americans) were included in the analysis. After adjustment for baseline risk factors, higher LV mass (β = 0.17; P< .0001), lower ejection fraction (β = -0.32; P = < .0001), higher hs-cTnT levels (β = 0.06; P= 0.04), and lower CRF (β = -0.16; P< .0001) were each associated with higher Ecc (indicating worse systolic function). Higher WC was also significantly associated with higher Ecc (β = 0.07; P= .0006) while %BF was not associated with Ecc (P= 0.08). The relationship between CRF and Ecc did not change after additional adjustment for %BF and other significant confounders (Table).
Conclusion: Lower CRF, but not total body fat, is associated with reduced peak systolic strain independent of LV mass and ejection fraction.These findings highlight the independent contributions of low fitness in mid-life towards heart failure risk at a later age.
Author Disclosures: A. Pandey: None. C. Ayers: None. I.J. Neeland: None. S. Matulevicius: None. A. Rohatgi: None. R. Peshock: None. M. Drazner: None. S. Sarma: None. J. De Lemos: Consultant/Advisory Board; Modest; Novo Nordisc, St. Jude Medical. Research Grant; Significant; Roche Diagnostics, Abbott Diagnostics. J.D. Berry: None.
- © 2015 by American Heart Association, Inc.