title: Endothelium-dependent acetylcholine-induced vasodilatory response of saphenous vein grafts.
abstract: BACKGROUND
  It has been suggested that endothelial dysfunction is critical to saphenous vein graft (SVG) occlusion.
  
  
  OBJECTIVE
  To evaluate in vivo endothelium-mediated vasoreactivity in angiographically non-stenotic SVG.
  
  
  METHODS
  The group consisted of 31 patients (pts), aged 58.7+/-8.7 years, 54+/-38 months after coronary bypass surgery. In each patient one angiographically normal SVG was selected for the study. Endothelium-dependent vasoreactivity was investigated with acetylcholine (Ach) 50 microg intragraft infusion. Graft diameter changes were measured by quantitative computer angiography (QCA).
  
  
  RESULTS
  In 17 (54.8%) pts there was a significant reduction in graft diameter following Ach infusion, from 3.8+/-0.7 to 3.2+/-0.7 mm (p=0.0001), whereas in 4 (12.9%) pts there were no diameter changes (3.2+/-0.7 mm). In the 10 remaining pts (32.3%) we found graft dilatation from 3.5+/-0.5 mm to 3.9+/-0.5 mm (p=0.0002). In multivariate linear regression analysis, SVG dilatation positively correlated with a low ratio of graft/artery diameter (p <0.002), high HDL-cholesterol level (p <0.001) and absence of hypertension (p <0.03), and negatively correlated with postoperative myocardial infarction (p <0.01).
  
  
  CONCLUSIONS
  Endothelium-dependent vasodilatory response to Ach is present in one third of old SVG. Dilative response to Ach 50 is better preserved in SVG with smaller difference between graft/grafted artery diameters. Adequate matching of the graft/grafted artery diameters probably preserves the endothelium-dependent dilative response of the graft.
authors.affiliation: Instytut Kardiologii, ul. Alpejska 42, 04-628 Warsaw, Poland. aciszewski@interia.pl
authors.forename: Andrzej
authors.initials: A
authors.lastname: Ciszewski
authors.forename: Cezary
authors.initials: C
authors.lastname: Kepka
authors.forename: Walerian
authors.initials: W
authors.lastname: Piotrowski
authors.forename: Adam
authors.initials: A
authors.lastname: Witkowski
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology*; D000368:Aged; D000792:Angiography; D001158:Arteries / Q000187:drug effects / Q000503:physiopathology; D001026:Coronary Artery Bypass / Q000379:methods; D004727:Endothelium / Q000187:drug effects* / Q000502:physiology; D005260:Female; D006085:Graft Survival / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012501:Saphenous Vein / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000637:transplantation*; D013997:Time Factors; D014661:Vasoconstriction / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects*
chemical_list: D000109:Acetylcholine