title: Effect of Chlamydia pneumoniae infection on coronary flow reserve and intimal hyperplasia after stent implantation in patients with angina pectoris.
abstract: OBJECTIVE
  Chlamydia pneumoniae (C. pneumoniae) has been detected in tissue from coronary atherosclerotic vascular lesions and may be involved in the pathogenesis of atherosclerosis. However, the effect of prior C. pneumoniae infection on coronary intimal hyperplasia after stent implantation and on coronary microvascular function is unknown.
  
  
  METHODS
  Seventy-three patients with stable angina pectoris and a single de novo coronary lesion were studied prospectively. All patients underwent successful coronary angioplasty and stent implantation for the stenotic lesion. Blood samples were tested for prior C. pneumoniae infection before the procedure, and patients were divided into two groups: Seropositive and seronegative. Coronary flow reserve was measured in the non-stenotic coronary vessel before angioplasty, and quantitative coronary arteriography was performed at the stent implantation site before angioplasty and 6 months later in all patients.
  
  
  RESULTS
  Coronary flow reserve in the non-stenotic vessel was significantly lower in the seropositive group than in the seronegative group (2.51 +/- 0.35 vs 2.76 +/- 0.43, p < 0.05). The minimum luminal diameter was smaller and late loss was greater in the seropositive group than in the seronegative group (minimum luminal diameter: 1.52 +/- 0.59 vs 1.91 +/- 0.79 mm, p < 0.05, late loss: 1.17 +/- 0.55 vs 0.76 +/- 0.67, p < 0.05). However, there was no significant difference in the restenosis rate or target lesion revascularization rate between the two groups.
  
  
  CONCLUSIONS
  Prior C. pneumoniae infection may accelerate intimal hyperplasia after stent implantation and impair coronary microvascular function in the non-stenotic coronary vessels.
authors.affiliation: Department of Cardiology, Showa General Hospital, Tenjin-cho 2-450, Kodaira, Tokyo 187-8510.
authors.forename: T
authors.initials: T
authors.lastname: Tanaka
authors.forename: M
authors.initials: M
authors.lastname: Matsushita
authors.forename: Y
authors.initials: Y
authors.lastname: Oka
authors.forename: T
authors.initials: T
authors.lastname: Sada
authors.forename: Y
authors.initials: Y
authors.lastname: Kira
mesh_terms: D000368:Aged; D000787:Angina Pectoris / Q000473:pathology* / Q000503:physiopathology / Q000628:therapy*; D015906:Angioplasty, Balloon, Coronary; D001783:Blood Flow Velocity; D002690:Chlamydia Infections / Q000150:complications* / Q000503:physiopathology; D016993:Chlamydophila pneumoniae; D003326:Coronary Circulation; D023903:Coronary Restenosis / Q000209:etiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D006965:Hyperplasia; D008297:Male; D008875:Middle Aged; D015607:Stents / Q000009:adverse effects*; D017539:Tunica Intima / Q000473:pathology*