title: Impact of dye injection on intracoronary pressure.
abstract: OBJECTIVE
  Coronary angiography is widely used to estimate coronary blood flow velocity, as in the TIMI frame count method. However, it is unknown to what extent the injection of dye elevates intracoronary pressure which may accelerate coronary blood flow velocity. In the present study, intracoronary pressure was measured during coronary angiography.
  
  
  RESULTS
  In 25 patients with non-significant coronary lesions, assessed by fractional flow reserve measurement with a pressure guidewire, we recorded intracoronary pressure during dye injection for coronary angiography in the ostium of the coronary artery as well as distal to the lesion. There was a rise in mean intracoronary pressure during dye injection in both ostial and distal coronary arterial segments (from 90.8 +/- 17.2 mmHg to 96.8 +/- 18.5 mmHg and from 89.7 +/- 15.3 mmHg to 93.6 +/- 17.3 mmHg, respectively; p<0.001). Nevertheless, the absolute and relative increase in pressure was small (6.0 +/- 4.2 mmHg [6.7 +/- 4.9%] in the ostium, and 3.9 +/- 5.5 mmHg [4.2 +/- 5.7%] distally).
  
  
  CONCLUSIONS
  In coronary arteries without significant stenosis, coronary angiography causes only a minor increase in intracoronary pressure. The limited impact of dye injection on intracoronary blood pressure confirms the value of coronary angiography for estimation of coronary flow velocity.
authors.affiliation: Thorax Centre Twente, Medisch Spectrum Twente, Department of Cardiology, Enschede, The Netherlands. m.stoel@ziekenhuis-mst.nl
authors.forename: Martin
authors.initials: M
authors.lastname: Stoel
authors.forename: Jasveen
authors.initials: J
authors.lastname: Kandhai-Ragunath
authors.forename: Gert
authors.initials: G
authors.lastname: Van Houwelingen
authors.forename: Clemens
authors.initials: C
authors.lastname: Von Birgelen
mesh_terms: D000368:Aged; D001783:Blood Flow Velocity / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects*; D006328:Cardiac Catheterization; D003287:Contrast Media / Q000008:administration & dosage*; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology; D003326:Coronary Circulation / Q000187:drug effects*; D005260:Female; D006801:Humans; D007269:Injections, Intra-Arterial; D008297:Male; D008875:Middle Aged; D014283:Triiodobenzoic Acids / Q000008:administration & dosage*
chemical_list: D003287:Contrast Media; D014283:Triiodobenzoic Acids; C044834:iodixanol