title: Impairment of systemic microvascular endothelial and smooth muscle function in individuals with early-onset coronary artery disease: studies with laser speckle contrast imaging.
abstract: OBJECTIVE
  The assessment of systemic microvascular reactivity is currently considered to be critical in the stratification of cardiovascular risk. In the present study, we compared skin microvascular function in individuals with early-onset (premature) coronary artery disease (EOCAD, n=30) with that of age-matched and sex-matched healthy individuals (n=30).
  
  
  METHODS
  Using laser speckle contrast imaging, cutaneous blood flow was assessed in the forearm at rest and during reactivity tests, including postocclusive reactive hyperemia and the iontophoresis of acetylcholine or sodium nitroprusside with increasing currents of 30, 60, 90, 120, 150, and 180 μA for 10-s intervals spaced 1 min apart. Carotid intima-media thickness was evaluated using an ultrasound system and a 7.5 MHz ultrasound transducer.
  
  
  RESULTS
  The endothelium-dependent skin microvascular vasodilator responses that were induced by both acetylcholine and postocclusive reactive hyperemia were significantly reduced in patients with EOCAD compared with healthy individuals. The vasodilator responses that were induced by sodium nitroprusside were also significantly reduced in individuals with EOCAD. These systemic microvascular alterations were concurrent with increased carotid intima-media thickness in these patients.
  
  
  CONCLUSIONS
  Laser speckle contrast imaging identifies endothelial-dependent and endothelial-independent microvascular dysfunction in individuals presenting with EOCAD, and thus could be valuable as an early peripheral marker of atherothrombotic disease.
authors.affiliation: aNational Institute of Cardiology (INC) bLaboratory of Cardiovascular Investigation, Oswaldo Cruz Institute cFaculty of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Elaine G
authors.initials: EG
authors.lastname: Souza
authors.forename: Andrea
authors.initials: A
authors.lastname: De Lorenzo
authors.forename: Grazielle
authors.initials: G
authors.lastname: Huguenin
authors.forename: Glaucia M M
authors.initials: GM
authors.lastname: Oliveira
authors.forename: Eduardo
authors.initials: E
authors.lastname: Tibiriçá
mesh_terms: D000279:Administration, Cutaneous; D000328:Adult; D017668:Age of Onset; D001783:Blood Flow Velocity; D059168:Carotid Intima-Media Thickness; D016022:Case-Control Studies; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D004730:Endothelium, Vascular / Q000187:drug effects / Q000503:physiopathology*; D005260:Female; D005542:Forearm; D006801:Humans; D007478:Iontophoresis; D017078:Laser-Doppler Flowmetry; D008297:Male; D008833:Microcirculation / Q000187:drug effects; D055806:Microvessels / Q000503:physiopathology; D008875:Middle Aged; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000503:physiopathology*; D011237:Predictive Value of Tests; D012039:Regional Blood Flow; D012867:Skin / Q000098:blood supply*; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents / Q000008:administration & dosage
chemical_list: D014665:Vasodilator Agents