title: Impaired coronary microvascular endothelial function in men with metabolic syndrome.
abstract: OBJECTIVE
  To assess coronary endothelial function of conduit and resistance vessels in patients with metabolic syndrome (MS).
  
  
  METHODS
  Seventy-eight men (mean age, 57 years) with chest pain and angiographically normal coronary arteries were included in the study. Patients with coronary spastic angina were excluded. Changes in coronary artery diameter and coronary blood flow (CBF) in response to acetylcholine (ACh) were determined using quantitative coronary angiography and Doppler velocity measurements. Coronary flow reserve was calculated as the ratio of coronary blood velocity after adenosine triphosphate infusion relative to baseline values. Patients were divided into two groups based on the presence or absence of MS.
  
  
  RESULTS
  There were 24 patients in the MS group (31%). The increase in CBF in response to ACh infusion was impaired in the MS group (P < 0.0001) compared to the non-MS group, whereas changes in coronary artery diameter in response to ACh infusion did not differ between the two groups. Multivariate regression analysis revealed that MS was a significant factor associated with the lesser change in CBF induced by ACh infusion at 30 μg/min (P < 0.0001, r(2) = 0.46).
  
  
  CONCLUSIONS
  Coronary endothelial dysfunction was present at the level of resistance vessels but not conduit vessels in the MS patients included in our study.
authors.affiliation: Hiroki Teragawa, Department of Cardiovascular Medicine, Hiroshima General Hospital of West Japan Railway Company, 3-1-36, Futabanosato, Higashi-ku, Hiroshima 732-0057, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Teragawa
authors.forename: Naoya
authors.initials: N
authors.lastname: Mitsuba
authors.forename: Kenji
authors.initials: K
authors.lastname: Nishioka
authors.forename: Kentaro
authors.initials: K
authors.lastname: Ueda
authors.forename: Shingo
authors.initials: S
authors.lastname: Kono
authors.forename: Yukihito
authors.initials: Y
authors.lastname: Higashi
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Chayama
authors.forename: Yasuki
authors.initials: Y
authors.lastname: Kihara