Effects of supplemental oxygen administration on coronary blood flow in patients undergoing cardiac catheterization.
Patients with heart disease are frequently treated with supplemental oxygen. Although oxygen can exhibit vasoactive properties in many vascular beds, its effects on the coronary circulation have not been fully characterized. To examine whether supplemental oxygen administration affects coronary blood flow (CBF) in a clinical setting, we measured in 18 patients with stable coronary heart disease the effects of breathing 100% oxygen by face mask for 15 min on CBF (via coronary Doppler flow wire), conduit coronary diameter, CBF response to intracoronary infusion of the endothelium-dependent dilator ACh and to the endothelium-independent dilator adenosine, as well as arterial and coronary venous concentrations of the nitric oxide (NO) metabolites nitrotyrosine, NO(2)(-), and NO(3)(-). Relative to breathing room air, breathing of 100% oxygen increased coronary resistance by approximately 40%, decreased CBF by approximately 30%, increased the appearance of nitrotyrosine in coronary venous plasma, and significantly blunted the CBF response to ACh. Oxygen breathing elicited these changes without affecting the diameter of large-conduit coronary arteries, coronary venous concentrations of NO(2)(-) and NO(3)(-), or the coronary vasodilator response to adenosine. Administering supplemental oxygen to patients undergoing cardiac catheterization substantially increases coronary vascular resistance by a mechanism that may involve oxidative quenching of NO within the coronary microcirculation.
McNulty
Patrick H
PH
Department of Medicine, Pennsylvania State College of Medicine, Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033, USA. pmcnulty@psu.edu <pmcnulty@psu.edu>
King
Nicholas
N
Scott
Sofia
S
Hartman
Gretchen
G
McCann
Jennifer
J
Kozak
Mark
M
Chambers
Charles E
CE
Demers
Laurence M
LM
Sinoway
Lawrence I
LI
D000109:Acetylcholine / Q000008:administration & dosage; D000241:Adenosine / Q000008:administration & dosage; D000328:Adult; D000368:Aged; D006328:Cardiac Catheterization; D003326:Coronary Circulation / Q000187:drug effects* / Q000502:physiology*; D003327:Coronary Disease / Q000175:diagnosis* / Q000188:drug therapy* / Q000503:physiopathology; D004347:Drug Interactions; D019332:Endothelin-1 / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009566:Nitrates / Q000097:blood; D009569:Nitric Oxide / Q000097:blood; D009573:Nitrites / Q000097:blood; D010100:Oxygen / Q000008:administration & dosage* / Q000097:blood; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000097:blood; D014665:Vasodilator Agents / Q000008:administration & dosage
D019332:Endothelin-1; D009566:Nitrates; D009573:Nitrites; D014665:Vasodilator Agents; D009569:Nitric Oxide; C002744:3-nitrotyrosine; D014443:Tyrosine; D000241:Adenosine; D000109:Acetylcholine; D010100:Oxygen