title: Myocardial oxygen utilization after reversible global ischemia.
abstract: We tested in 20 sheep the hypothesis that oxygen consumption increases after reversible, global myocardial ischemia. Left ventricular oxygen consumption before and after 25 minutes of warm (37 degrees C) global ischemia was linearly related to a function (integral) of left ventricular circumferential systolic wall stress, altered by changing afterload. The relation is expressed in the two regression equations: LVO2 (preischemic) = 1.06.SSI + 16.8 (n = 129; r = 0.79); LVO2 (postischemic) = 4.35.SSI + 5.6 (n = 89; r = 0.65). The fourfold increase in slope (4.35 versus 1.06) indicates (p = 0.0001) a massive increase of oxygen consumption in postischemic, globally "stunned" myocardium. The inferences are that globally stunned myocardium causes severe impairment of oxygen utilization efficiency, and increased vulnerability to further ischemia if coronary vessels are diseased.
authors.affiliation: Division of Cardiothoracic Surgery, University of Pennsylvania, Philadelphia.
authors.forename: J E
authors.initials: JE
authors.lastname: Bavaria
authors.forename: S
authors.initials: S
authors.lastname: Furukawa
authors.forename: G
authors.initials: G
authors.lastname: Kreiner
authors.forename: M B
authors.initials: MB
authors.lastname: Ratcliffe
authors.forename: J
authors.initials: J
authors.lastname: Streicher
authors.forename: D K
authors.initials: DK
authors.lastname: Bogen
authors.forename: L H
authors.initials: LH
authors.lastname: Edmunds
mesh_terms: D000818:Animals; D009200:Myocardial Contraction / Q000502:physiology*; D015428:Myocardial Reperfusion Injury / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism*; D010101:Oxygen Consumption; D012044:Regression Analysis; D012756:Sheep