the influence of basal heart rate ( hr ) on the effects of inotropic ( dobutamine infusion ) and chronotropic ( atrial pacing ) stimuli during acute myocardial ischemia was assessed by measurement of intramural carbon dioxide partial pressure ( pco2 ) in open-chest dogs undergoing transient 10-minute left anterior descending coronary artery occlusions .
C0018787
heart
C0018792
atrial