title: Vasoreactivity and restenosis after coronary angioplasty in the atherosclerotic pig model.
abstract: BACKGROUND
  The effect of coronary angioplasty on coronary spasm remains unknown. We examined the effects of balloon angioplasty, using an oversized balloon, on coronary hypercontraction and eventual restenosis in a pig model of coronary spasm.
  
  
  METHODS
  We performed balloon angioplasty, using an oversized balloon at the site of coronary spasm superimposed on atherosclerosis with 6 (group A, n = 14) or 1 (group B, n = 14) atmospheres of inflation pressure in miniature pigs. Using coronary angiography we assessed the coronary basal diameter and diameter change in response to histamine and serotonin before, immediately after, and 4 weeks after angioplasty. Histological examinations were performed immediately after and 4 weeks after the angioplasty.
  
  
  RESULTS
  Before angioplasty, histamine- and serotonin-induced hypercontraction was reproducibly noted at the atherosclerotic site. Immediately after angioplasty, the coronary diameter became larger (P < 0.01) than before angioplasty in group A, but there was no significant difference in group B. The hypercontraction in group A was abolished immediately after and 4 weeks after angioplasty, whereas the hypercontraction in group B was unchanged. Histological examination revealed medial necrosis immediately after and medial fibrosis 4 weeks after angioplasty, which were more prominent in group A. Four weeks after angioplasty, the magnitude of restenosis was greater in group A than in group B.
  
  
  CONCLUSIONS
  Angioplasty using an oversized balloon with the higher atmosphere of inflation pressure abolished coronary hypercontraction immediately after and 4 weeks after angioplasty, which probably resulted from the irreversible damage to medial smooth muscles; however, this did not prevent restenosis.
authors.affiliation: Research Institute of Angiocardiology and Cardiovascular Clinic, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Hata
authors.forename: Y
authors.initials: Y
authors.lastname: Ohara
authors.forename: T
authors.initials: T
authors.lastname: Kuga
authors.forename: T
authors.initials: T
authors.lastname: Fukai
authors.forename: H
authors.initials: H
authors.lastname: Kasuya
authors.forename: H
authors.initials: H
authors.lastname: Tomoike
authors.forename: A
authors.initials: A
authors.lastname: Takeshita
mesh_terms: D015906:Angioplasty, Balloon, Coronary; D000818:Animals; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery*; D003331:Coronary Vessels / Q000502:physiology*; D004195:Disease Models, Animal; D008297:Male; D012008:Recurrence; D013552:Swine; D014666:Vasomotor System