The proinflammatory cytokines have been implicated in mediating myocardial dysfunction associated with myocardial infarction, severe congestive heart failure, and sepsis. We tested the hypothesis that cytokine levels are elevated after uncomplicated coronary artery bypass grafting and associated with episodes of postoperative myocardial ischemia and dysfunction. Coronary artery bypass grafting was performed under general anesthesia with moderate systemic hypothermia and cold-blood potassium cardioplegic solution. Tumor necrosis factor-a and interleukin-6 levels were determined by bioassays, and interleukin-8 levels were measured by a sandwich enzyme-linked immunosorbent assay. Myocardial function and ischemic episodes were assessed by intraoperative transesophageal echocardiography and perioperative 12-channel Holter monitoring. A total of 22 patients were studied, with no deaths or complications. Arterial tumor necrosis factor-a rose in a bimodal distribution, peaking at 2 and 18 to 24 hours after the operation (at 20.2 ± 6.4 pg/ml, [mean ± standard error of the meanj) and 5.8 ± 1.6 pg/m1, respectively; before cardiopulmonary bypass: 0.90 ± 0.20 pg/ml, P < 0.001 for both peaks) then progressively declined to levels before bypass. Arterial interleukin-6 was maximally elevated immediately on termination of cardiopulmonary bypass and peaked again 12 to 18 hours after cardiopulmonary bypass (at 7520 ± 2439 pg/ml and 6216 ± 1928 pg/ml, respectively; before bypass: 746 ± 187 pg/m1, P < 0.0001 for both peaks). Arterial interleukin-8 levels were more variable but followed a similar pattern, peaking in the early period after cardiopulmonary bypass and again at 16 to 18 hours after the operation (at 4110 ± 1403 pg/ml and 1760 ± 1145 pg/ml, respectively; before bypass: 461 ± 158. p < 0.05 for both peaks). By multivariate analysis, the aortic crossclamp time was independently predictive of postoperative cytokine levels. Left ventricular wall motion abnormalities were associated with both interleukin-6 and interleukin-8 levels, worsening scores being associated with increasing levels (for interleukin-6, p = 0.003; for interleukin-8, p = 0.05). Postoperative myocardial ischemic episodes were associated with interleukin-6 levels, six of seven (85 %) patients with episodes of myocardial ischemia after a peak in interleukin-6 concentrations (p < 0.01). We conclude that proinflammatory cytokines are elevated after uncomplicated coronary revascularization and may contribute to postoperative myocardial ischemia and segmental wall motion abnormalities.

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Thin-section CT, including expiratory scans, is of limited accuracy in diagnosing early bronchiolitis obliterans after lung transplantation.

Sympathetic reinnervation of the transplanted human heart can occur > 1 year after operation, as assessed by I-123 MIBG imaging and the transmyocardial release of norepinephrine. Reinnervation is less likely to occur in patients with a pretransplantation diagnosis of idiopathic cardiomyopathy than in those with other etiologies of congestive heart failure.

Our results suggest that the response to graded dobutamine infusion in the post-cardiopulmonary bypass period differs from that previously reported. After cardiopulmonary bypass, the dominant mechanism by which dobutamine improves left ventricular performance is by increasing heart rate. Dobutamine affects blood pressure minimally.