title: Impaired flow-mediated vasodilation of the brachial artery in patients with primary hyperparathyroidism improves after parathyroidectomy.
abstract: OBJECTIVE
  The endothelium is a newly recognised target tissue of parathyroid hormone (PTH). It is not clear whether hyperparathyroidism affects endothelial function and whether parathyroidectomy (Ptx) has an influence on arterial vessel wall properties. We studied brachial flow-mediated vasodilation (FMD) and brachial and carotid intima-media thickness (IMT) in patients with primary hyperparathyroidism (pHPT) before and after Ptx and in healthy controls.
  
  
  METHODS
  19 patients with pHPT (mean+SEM, age 45+/-4.7 years, PTH 238+/-52 ng/l) were studied. Diabetes, hypertension and vascular disease were excluded. Twenty healthy volunteers matched for age, sex and blood pressure served as controls. Enddiastolic diameter, FMD and nitroglycerine-induced (NMD) dilation of the brachial artery were measured by a multigate pulsed doppler system (echo-tracking), IMT was determined using automatic analysis of the M-line signal. Healthy volunteers where studied on one occasion, patients were studied at baseline and 6 months after Ptx.
  
  
  RESULTS
  Six months after Ptx PTH had decreased to normal, blood pressure levels remained unchanged. Endothelium dependent FMD at baseline was impaired in patients compared to controls (4.7+/-1.2 vs. 18.2+/-3.7%, P<0.01), however, FMD improved significantly after Ptx (16.7+/-3.0%, P<0.01). Nitroglycerine-induced dilation, IMT and artery diameter were not different between groups and did not change after Ptx.
  
  
  CONCLUSIONS
  Impaired endothelium dependent vasodilation in patients with primary hyperparathyroidism improves after successful parathyroidectomy. Endothelial dysfunction associated with primary hyperparathyroidism occurs without detectable structural wall alterations of the brachial artery and appears therefore to be an early and reversible arterial alteration.
authors.affiliation: Department of Internal Medicine D, University of Münster, Albert-Schweitzer-Strasse 33, D-48129, Münster, Germany. koschm@uni-muenster.de
authors.forename: M
authors.initials: M
authors.lastname: Kosch
authors.forename: M
authors.initials: M
authors.lastname: Hausberg
authors.forename: K
authors.initials: K
authors.lastname: Vormbrock
authors.forename: K
authors.initials: K
authors.lastname: Kisters
authors.forename: G
authors.initials: G
authors.lastname: Gabriels
authors.forename: K H
authors.initials: KH
authors.lastname: Rahn
authors.forename: M
authors.initials: M
authors.lastname: Barenbrock
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001794:Blood Pressure; D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D006801:Humans; D006961:Hyperparathyroidism / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D005996:Nitroglycerin; D016105:Parathyroidectomy; D011184:Postoperative Period; D012039:Regional Blood Flow; D014463:Ultrasonography; D014664:Vasodilation; D014665:Vasodilator Agents
chemical_list: D014665:Vasodilator Agents; D005996:Nitroglycerin