title: Effects of selective alpha1- and alpha2-adrenergic blockade on coronary flow reserve after coronary stenting.
abstract: BACKGROUND
  Coronary flow reserve (CFR) is not normalized shortly after coronary stenting. We hypothesized that alpha-adrenergic coronary vasoconstriction acts to limit CFR.
  
  
  RESULTS
  We assessed flow velocity by Doppler wires and cross-sectional area by angiography in 46 patients undergoing coronary culprit lesion stenting (81+/-4% stenosis). Hyperemia was induced by adenosine (24 micro g IC or 140 micro g/kg per minute IV) before and after stenting. Finally, either the alpha(1)-antagonist urapidil (10 mg IC) or the alpha(2)-antagonist yohimbine (3 mg IC) was randomly combined with adenosine. In 8 subjects with angiographically normal coronary arteries, CFR was increased from 3.21+/-0.30 to 3.74+/-0.43 by yohimbine and to 4.58+/-0.65 by urapidil, respectively (P=0.0001). Patients were divided according to the cutoff of CFR > or =3.0 (n=18) or <2.5 (n=28). Revascularization per se did not change CFR. However, 15 minutes after stenting, CFR decreased to 2.05+/-0.55 from CFR 3.64+/-0.58, whereas in patients with CFR 2.39+/-0.51, it remained unchanged. Yohimbine improved CFR to 3.26+/-0.42 and to 3.41+/-0.58 in patients with >3.0 and <2.05+/-0.55 baseline CFR, respectively. Urapidil improved CFR to 3.52+/-0.30 and 3.98+/-1.07, respectively.
  
  
  CONCLUSIONS
  Urapidil and yohimbine attenuated the CFR impairment occurring after revascularization by increasing both the epicardial vasodilator effect of adenosine and the blood flow velocity, thus suggesting that the adrenergic system plays an important role in limiting the capacity of the coronary circulation to dilate.
authors.affiliation: Experimental Surgery and Transplantation Institute, Ospedale Maggiore IRCCS, University of Milano, Italy. Luisa.Gregorini@unimi.it
authors.forename: Luisa
authors.initials: L
authors.lastname: Gregorini
authors.forename: Jean
authors.initials: J
authors.lastname: Marco
authors.forename: Bruno
authors.initials: B
authors.lastname: Farah
authors.forename: Monique
authors.initials: M
authors.lastname: Bernies
authors.forename: Carlo
authors.initials: C
authors.lastname: Palombo
authors.forename: Michaela
authors.initials: M
authors.lastname: Kozàkovà
authors.forename: Irene M
authors.initials: IM
authors.lastname: Bossi
authors.forename: Bernard
authors.initials: B
authors.lastname: Cassagneau
authors.forename: Jean
authors.initials: J
authors.lastname: Fajadet
authors.forename: Carlo
authors.initials: C
authors.lastname: Di Mario
authors.forename: Remo
authors.initials: R
authors.lastname: Albiero
authors.forename: Massimo
authors.initials: M
authors.lastname: Cugno
authors.forename: Adalberto
authors.initials: A
authors.lastname: Grossi
authors.forename: Gerd
authors.initials: G
authors.lastname: Heusch
mesh_terms: D000241:Adenosine / Q000009:adverse effects; D058668:Adrenergic alpha-1 Receptor Antagonists; D058669:Adrenergic alpha-2 Receptor Antagonists; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D001783:Blood Flow Velocity / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D017023:Coronary Angiography; D003326:Coronary Circulation / Q000187:drug effects*; D003327:Coronary Disease / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D003331:Coronary Vessels / Q000187:drug effects* / Q000503:physiopathology / Q000601:surgery; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000494:pharmacology; D015607:Stents; D014654:Vascular Patency / Q000187:drug effects; D015016:Yohimbine / Q000494:pharmacology
chemical_list: D058668:Adrenergic alpha-1 Receptor Antagonists; D058669:Adrenergic alpha-2 Receptor Antagonists; D000317:Adrenergic alpha-Antagonists; D010879:Piperazines; D015016:Yohimbine; C015568:urapidil; D000241:Adenosine