title: Reduced systemic arterial compliance impacts significantly on left ventricular afterload and function in aortic stenosis: implications for diagnosis and treatment.
abstract: OBJECTIVE
  We sought to determine to what extent systemic arterial compliance (SAC) might impact on afterload and left ventricular (LV) function in patients with aortic stenosis (AS).
  
  
  BACKGROUND
  Although AS and reduced SAC may often coexist in the same patient, their relative impact on LV function is not well understood.
  
  
  METHODS
  Systemic arterial compliance was calculated as the ratio of stroke volume index to arterial pulse pressure in 208 patients with at least moderate AS. As a measure of global afterload, we calculated the valvulo-arterial impedance (Zva), which theoretically accounts for the effects of both AS and SAC.
  
  
  RESULTS
  Patients were divided into four groups: group 1, moderate AS and normal SAC (n = 77; 37%); group 2, moderate AS and low SAC (n = 50; 24%); group 3, severe AS and normal SAC (n = 45; 22%); and group 4, severe AS and low SAC (n = 36; 17%). The prevalences of LV diastolic and systolic dysfunction were 60% and 6% in group 1, 86% and 12% in group 2, 82% and 16% in group 3, and 94% and 31% in group 4. In multivariate analysis excluding Zva, energy loss index and SAC were both independent predictors of LV dysfunction, but when Zva was entered into the analyses, it became the only hemodynamic variable to be independently associated with LV dysfunction.
  
  
  CONCLUSIONS
  Reduced SAC is a frequent occurrence in elderly patients with AS, where it independently contributes to increased afterload and decreased LV function. Systemic arterial compliance should be taken into consideration when evaluating these patients with regard to diagnosis and treatment.
authors: Research Group in Valvular Heart Diseases, Research Center of Laval Hospital/Quebec Heart Institute, Department of Medicine, Laval University, Sainte-Foy, Quebec, Canada.
authors: Martin
authors: M
authors: Briand
authors: Jean G
authors: JG
authors: Dumesnil
authors: Lyes
authors: L
authors: Kadem
authors: Antonio G
authors: AG
authors: Tongue
authors: Régis
authors: R
authors: Rieu
authors: Damien
authors: D
authors: Garcia
authors: Philippe
authors: P
authors: Pibarot
mesh_terms: D000368:Aged; D001024:Aortic Valve Stenosis / Q000503:physiopathology*; D001158:Arteries / Q000503:physiopathology*; D016022:Case-Control Studies; D003187:Compliance; D004562:Electrocardiography; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D015995:Prevalence; D011674:Pulse; D012189:Retrospective Studies; D013318:Stroke Volume / Q000502:physiology; D018487:Ventricular Dysfunction, Left / Q000453:epidemiology* / Q000503:physiopathology; D016277:Ventricular Function, Left / Q000502:physiology