title: Association of cardiorespiratory fitness with left ventricular remodeling and diastolic function: the Cooper Center Longitudinal Study.
abstract: OBJECTIVE
  This study sought to compare the cross-sectional associations between fitness and echocardiographic measures of cardiac structure and function.
  
  
  BACKGROUND
  Cardiorespiratory fitness is inversely associated with heart failure risk. However, the mechanism through which fitness lowers heart failure risk is not fully understood.
  
  
  METHODS
  We included 1,678 men and 1,247 women from the Cooper Center Longitudinal Study who received an echocardiogram from 1999 to 2011. Fitness was estimated by Balke protocol (in metabolic equivalents) and also categorized into age-specific quartiles, with quartile 1 representing low fitness. Cross-sectional associations between fitness (in metabolic equivalents) and relative wall thickness, left ventricular end-diastolic diameter indexed to body surface area, left atrial volume indexed to body surface area, left ventricular systolic function, and E/e' ratio were determined using multivariable linear regression analysis.
  
  
  RESULTS
  Higher levels of mid-life fitness (metabolic equivalents) were associated with larger indexed left atrial volume (men: beta = 0.769, p < 0.0001; women: beta = 0.879, p value ≤0.0001) and indexed left ventricular end-diastolic diameter (men: beta = 0.231, p < 0.001; women: beta = 0.264, p < 0.0001). Similarly, a higher level of fitness was associated with a smaller relative wall thickness (men: beta = -0.002, p = 0.04; women: beta = -0.005, p < 0.0001) and E/e' ratio (men: beta = -0.11, p = 0.003; women: beta = -0.13, p = 0.01). However, there was no association between low fitness and left ventricular systolic function (p = NS).
  
  
  CONCLUSIONS
  Low fitness is associated with a higher prevalence of concentric remodeling and diastolic dysfunction, suggesting that exercise may lower heart failure risk through its effect on favorable cardiac remodeling and improved diastolic function.
authors: Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, Texas.
authors: Stephanie K
authors: SK
authors: Brinker
authors: Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, Texas.
authors: Ambarish
authors: A
authors: Pandey
authors: Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, Texas.
authors: Colby R
authors: CR
authors: Ayers
authors: The Cooper Institute, Dallas, Texas.
authors: Carolyn E
authors: CE
authors: Barlow
authors: The Cooper Institute, Dallas, Texas.
authors: Laura F
authors: LF
authors: DeFina
authors: The Cooper Institute, Dallas, Texas.
authors: Benjamin L
authors: BL
authors: Willis
authors: The Cooper Clinic, Dallas, Texas.
authors: Nina B
authors: NB
authors: Radford
authors: Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, Texas.
authors: Ramin
authors: R
authors: Farzaneh-Far
authors: Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, Texas.
authors: James A
authors: JA
authors: de Lemos
authors: Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, Texas.
authors: Mark H
authors: MH
authors: Drazner
authors: Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, Texas. Electronic address: jarett.berry@utsouthwestern.edu.
authors: Jarett D
authors: JD
authors: Berry
mesh_terms: D002306:Cardiac Volume / Q000502:physiology; D003430:Cross-Sectional Studies; D004452:Echocardiography; D005080:Exercise Test; D005260:Female; D006325:Heart Atria / Q000473:pathology / Q000503:physiopathology; D054144:Heart Failure, Diastolic / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology*; D009929:Organ Size; D010809:Physical Fitness / Q000502:physiology*; D013318:Stroke Volume / Q000502:physiology; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology; D020257:Ventricular Remodeling / Q000502:physiology*
keywords: diastolic dysfunction; echocardiography; exercise; heart failure; remodeling