title: Elevated C-reactive protein levels and coronary microvascular dysfunction in patients with coronary artery disease.
abstract: OBJECTIVE
  It is still unknown whether elevated C-reactive protein levels are responsible for coronary microcirculatory dysfunction in patients with coronary artery disease (CAD). This study was aimed at evaluating the association between C-reactive protein levels and endothelium-dependent and endothelium-independent coronary blood flow (CBF) responses in non-culprit arteries of patients with CAD.
  
  
  RESULTS
  We studied 28 patients (14 with normal and 14 with elevated C-reactive protein levels, >5 mg/L) with single-vessel disease and otherwise angiographically normal coronary arteries undergoing percutaneous transluminal coronary angioplasty (PTCA). CBF was measured in the non-PTCA vessel using an intracoronary Doppler guide wire and quantitative coronary angiography at baseline, after intracoronary infusion of substance P and of adenosine, and expressed as per cent change from baseline. The increases in CBF during infusion of substance P and of adenosine were lesser in patients with elevated than in those with normal C-reactive protein levels (34+/-22 vs. 61+/-34%, P=0.04 and 131+/-53 vs. 189+/-89%, P=0.03, respectively). Multivariable analysis identified elevated C-reactive protein level as the only independent predictor of reduced response to substance P (P=0.01) and adenosine (P=0.02).
  
  
  CONCLUSIONS
  In patients with CAD, evidence of systemic inflammation is independently associated with endothelium-dependent and endothelium-independent coronary microvascular dysfunction, which, in turn, may be critical to precipitate myocardial ischaemia, in particular, in unstable patients.
authors.affiliation: Division of Cardiology and Cardiac Surgery, Università di Roma Tor Vergata, European Hospital, via Portuense 700, 00149 Rome, Italy. f.tomai@tiscali.it
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Tomai
authors.forename: Flavio
authors.initials: F
authors.lastname: Ribichini
authors.forename: Anna S
authors.initials: AS
authors.lastname: Ghini
authors.forename: Valeria
authors.initials: V
authors.lastname: Ferrero
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Andò
authors.forename: Corrado
authors.initials: C
authors.lastname: Vassanelli
authors.forename: Francesco
authors.initials: F
authors.lastname: Romeo
authors.forename: Filippo
authors.initials: F
authors.lastname: Crea
authors.forename: Luigi
authors.initials: L
authors.lastname: Chiariello
mesh_terms: D000241:Adenosine / Q000494:pharmacology; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001783:Blood Flow Velocity / Q000187:drug effects / Q000502:physiology; D002097:C-Reactive Protein / Q000378:metabolism*; D016022:Case-Control Studies; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000097:blood* / Q000473:pathology / Q000503:physiopathology; D003326:Coronary Circulation / Q000187:drug effects / Q000502:physiology; D023921:Coronary Stenosis / Q000097:blood* / Q000473:pathology / Q000503:physiopathology; D004730:Endothelium, Vascular / Q000503:physiopathology; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008833:Microcirculation / Q000502:physiology; D017566:Microvascular Angina / Q000097:blood / Q000503:physiopathology; D008875:Middle Aged; D013373:Substance P / Q000494:pharmacology; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D014665:Vasodilator Agents; D013373:Substance P; D002097:C-Reactive Protein; D000241:Adenosine