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Although glucose uptake is increased in chronically hypoperfused, viable myocardium, the dynamic changes in glucose uptake relative to oxygen consumption in "short-term" models of hibernation have not been fully explored.14 anesthetized swine were instrumented with an hydraulic occluder and flow probe on the proximal LAD artery. Blood flow was reduced approximately 30% for 1 hour. Myocardial blood flow and uptake of oxygen, free fatty acids, glucose and lactate were determined in the LAD region at baseline and at 10, 30, and 60 minutes of ischemia. Transmural biopsies for ATP and creatine phosphate (CP) were obtained in the LAD region prior to and at 15 and 45 minutes of ischemia. In 5 animals, glycogen was assayed at baseline and at the end of 60 minutes of ischemia.In the LAD region, myocardial oxygen consumption was reduced from 2.06 +/- 0.16 micromol/min/gram to 1.46 +/- 0.13 micromol/min/gram (P0.05). By 15 minutes of ischemia, transmural creatine phosphate fell from 7.48 +/- 0.76 micromol/g-wet weight at baseline to 6.19 +/- 0.32 micromol/g-wet weight (P0.05) but normalized by 45 minutes of ischemia (7.39 +/- 0.56 micromol/g-wet weight; NS). Between 10 and 60 minutes of constant flow reduction, glucose uptake as a percentage of MVO2 increased from 3 +/- 2% to 10 +/- 2% (P0.05) while lactate uptake increased from -9 +/- 9% to -1 +/- 2% (P0.05). Glycogen decreased from 27.8 +/- 3.7 at baseline to 16.9 +/- 1.2 micromol/g-wet weight at end-ischemia.In this model of short-term hibernation, glucose and lactate uptake increase relative to oxygen consumption during sustained ischemia, and temporally coincide with the recovery of bioenergetics. The findings are consistent with the notion that glycolytically derived ATP is important for the maintainance of energy supply during sustained ischemia.

We reviewed our short- (30 days) and long-term (up to 17 years) experience with surgical revascularization for patients with angiographically documented isolated single-vessel coronary artery disease.Retrospective study of single-vessel coronary artery bypass procedures performed from January 1980 through June 1996. During this time, 100 consecutive patients underwent a single-vessel coronary artery bypass. All patients were men with a mean age of 59+/-9 years (range, 35 to 78 years) and a mean ejection fraction of 56+/-8% (range, 35 to 77%). The vessels bypassed included the left anterior descending in 66 (66%), right coronary artery in 31 (31%), and the obtuse marginal in 3 (3%).Short-term results reveal no deaths and six (6.0%) complications. Long-term follow-up by chart review and telephone survey was available in 87 (87%) patients at a mean of 46.9 months (range, 12 to 151 months). Cumulative freedom from angina and repeated revascularization was 93% and 98% at 1 year and 55% and 81% at 10 years, respectively (Kaplan-Meier).Single-vessel coronary artery bypass for isolated single-vessel disease can be performed with minimal morbidity and no mortality and provides excellent long-term relief of angina.

There is an abundance of information on the association between stressful life events and illness within the adult population. In contrast, research on this relationship among adolescents is limited. This study evaluated the role of individual differences (gender and race) on the stress-illness relationship within the adolescent population. Participants were 119 adolescents (54 females and 65 males), recruited from two public high schools located in the southeast, who were administered four questionnaires designed to measure levels of stress, anxiety, and illness. Overall, correlational analysis revealed that stress and anxiety were positively correlated with reported illness. However, racial and gender differences did emerge. Although no gender differences were found with regard to the experience of stress, African-American athletes reported a higher frequency of stressful life events than did their Euro-American counterparts. Further, African-American adolescents reported a lower frequency of illness than did the Euro-Americans. Females reported more illnesses than did males. Possible explanations for individual differences in reported stress and illness are discussed.