title: Sublingual microcirculation in pulmonary arterial hypertension.
abstract: BACKGROUND
  Pulmonary arterial hypertension (PAH) is a pulmonary vasculopathy that leads to failure of the right ventricle and premature death.
  
  
  OBJECTIVE
  To determine whether the sublingual microcirculation is affected in patients with PAH compared with healthy age- and sex-matched control subjects.
  
  
  METHODS
  Using the CapiScope Handheld Video Capillaroscope we measured the sublingual microvasculature density, flow index, tortuosity, and curvature. Videos were acquired immediately after right heart catheterization, and determinations were made off-line by investigators blinded to the group assignment or hemodynamics.
  
  
  RESULTS
  In this cross-sectional pilot study, we included 26 patients with PAH (age, mean ± SD, 56.7 ± 10 yr; 77% women) and 14 healthy control subjects (age, 53.1 ± 12 yr; 71% women). Sublingual microvasculature flow index was lower (2 ± 0.66 vs. 2.7 ± 0.37, P < 0.001) with higher heterogeneity index (0.63 ± 0.63 vs. 0.25 ± 0.25, P = 0.04) in patients with PAH than control subjects. Microvasculature density was similar between the groups, but tortuosity was more pronounced in patients than control subjects (tort 0: 45 ± 19 vs. 23.6 ± 12, P = 0.001 and tort 1: 0.2 ± 0.16 vs. 0.06 ± 0.04, P < 0.001).
  
  
  CONCLUSIONS
  Patients with PAH showed lower sublingual microvasculature flow index and higher tortuosity compared with healthy age- and sex-matched control subjects. Further investigations are needed to assess whether this methodology can provide information on disease prognosis and/or response to therapy in this condition.
authors.affiliation: Department of Pulmonary, Allergy, and Critical Care Medicine, Respiratory Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Luma
authors.initials: L
authors.lastname: Dababneh
authors.forename: Frank
authors.initials: F
authors.lastname: Cikach
authors.forename: Laith
authors.initials: L
authors.lastname: Alkukhun
authors.forename: Raed A
authors.initials: RA
authors.lastname: Dweik
authors.forename: Adriano R
authors.initials: AR
authors.lastname: Tonelli
mesh_terms: D000328:Adult; D000368:Aged; D006328:Cardiac Catheterization; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D006439:Hemodynamics; D006801:Humans; D006976:Hypertension, Pulmonary / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D008833:Microcirculation / Q000502:physiology*; D020678:Microscopic Angioscopy; D055806:Microvessels / Q000473:pathology / Q000503:physiopathology*; D008875:Middle Aged; D009060:Mouth Floor / Q000098:blood supply*; D010865:Pilot Projects; D012039:Regional Blood Flow