title: QPV interval as a measure of arterial stiffness in women with systemic lupus erythematosus.
abstract: BACKGROUND
  Systemic lupus erythematosus (SLE) is associated with premature atherosclerosis and increased arterial stiffness. The QPV interval has been proposed as a measure of arterial stiffness. The QPV interval is based on the premise that transit time from cardiac ejection to brachial artery flow is shortened in patients with increased arterial stiffness.
  
  
  OBJECTIVE
  The objective of this study was to determine the significance of the QPV interval as a measure of arterial stiffness in patients with SLE.
  
  
  METHODS
  We prospectively studied 46 female SLE patients. The QPV interval was calculated as the time from onset of the QRS complex to peak flow velocity of the brachial artery during ultrasound examination. Measurements of arterial stiffness: augmentation index (AI) and pulse wave velocity (PWV) were obtained by applanation tonometry while patients were on a stable medical regimen.
  
  
  RESULTS
  Mean age was 44+/-14 y and mean QPV interval was 198+/-18 msec QPV interval correlated inversely with age (r=-0.39, p=0.008), AI (r=-0.41, p=0.004), PWV (r=-0.39, p=0.007), and aortic pulse pressure (PP) (r=-0.45, p=0.002). On multivariate regression analysis, QPV interval was found to be an independent predictor of PWV after adjusting for age (R2=0.26, p<0.001).
  
  
  CONCLUSIONS
  In women with SLE, QPV decreases with age and is inversely related with measures of arterial stiffness. QPV may be useful in identifying SLE patients with higher arterial stiffness in the clinical or research setting. Further larger studies are needed to confirm these preliminary results.
authors.affiliation: Division of Cardiovascular Medicine, State University of New York, Downstate Medical Center, Brooklyn, NY 11203-2098, USA.
authors.forename: Ghazanfar
authors.initials: G
authors.lastname: Qureshi
authors.forename: Louis
authors.initials: L
authors.lastname: Salciccioli
authors.forename: Susan
authors.initials: S
authors.lastname: Lee
authors.forename: Mohammad
authors.initials: M
authors.lastname: Qureshi
authors.forename: Amit
authors.initials: A
authors.lastname: Kapoor
authors.forename: Ellen
authors.initials: E
authors.lastname: Ginzler
authors.forename: Jason M
authors.initials: JM
authors.lastname: Lazar
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology; D001916:Brachial Artery / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D006801:Humans; D016014:Linear Models; D008180:Lupus Erythematosus, Systemic / Q000503:physiopathology*; D008875:Middle Aged; D011446:Prospective Studies; D014463:Ultrasonography; D014655:Vascular Resistance / Q000502:physiology*