title: Left ventricular remodeling in human heart failure: quantitative echocardiographic assessment of 1,794 patients.
abstract: BACKGROUND
  The left ventricle (LV) undergoes significant architectural remodeling in heart failure (HF). However, the fundamental associations between cardiac function and LV size and performance have not been thoroughly characterized in this population. We sought to define the adaptive remodeling that occurs in chronic human HF through the detailed analyses of a large quantitative echocardiography database.
  
  
  METHODS
  Baseline echocardiograms were performed in 1,794 patients with HF across a broad range of ejection fraction (EF), from less than 10% to greater than 70%. Core lab measurements of LV volumes and length were made, from which EF, mass, sphericity indices, stroke volume (SV), and stroke work were derived. Spearman correlation coefficients and linear regression methods were used to determine the relationships between remodeling parameters.
  
  
  RESULTS
  The median EF was 28.6% (IQR 21.9-37.0). Across a multitude of parameters of cardiac structure and function, indexed end-systolic volumes (ESVs) explained the greatest proportion of the variance in EF (R =-0.87, P < 0.0001). Systolic sphericity index and LV mass were also strongly correlated with EF (R =-0.62 and -0.63, P < 0.0001), reflective of the alterations in LV shape and size that occur as EF declines. SV was rigorously maintained across a broad spectrum of EF, until the EF fell below 20%, at which point SV decreased significantly (P < 0.0001).
  
  
  CONCLUSIONS
  In chronic HF, the LV undergoes extensive structural adaptive remodeling in order to maintain SV across a broad range of EF. However, when the EF falls below 20%, further modulation of SV is no longer possible through alterations in ventricular architecture.
authors.affiliation: Division of Cardiovascular Medicine Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA. bonnie.ky@uphs.upenn.edu
authors.forename: Bonnie
authors.initials: B
authors.lastname: Ky
authors.forename: Ted
authors.initials: T
authors.lastname: Plappert
authors.forename: James
authors.initials: J
authors.lastname: Kirkpatrick
authors.forename: Frank E
authors.initials: FE
authors.lastname: Silvestry
authors.forename: Victor A
authors.initials: VA
authors.lastname: Ferrari
authors.forename: Martin G
authors.initials: MG
authors.lastname: Keane
authors.forename: Susan E
authors.initials: SE
authors.lastname: Wiegers
authors.forename: Julio A
authors.initials: JA
authors.lastname: Chirinos
authors.forename: Martin
authors.initials: M
authors.lastname: St John Sutton
mesh_terms: D000328:Adult; D000368:Aged; D015897:Comorbidity; D004452:Echocardiography / Q000706:statistics & numerical data*; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010414:Pennsylvania / Q000453:epidemiology; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D020257:Ventricular Remodeling