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Objectives: Endothelial dysfunction and C-reactive protein play a pivotal role in development of atherosclerosis and act as markers for future adverse cardiac events. Statins reduce C-reactive protein levels and improve endothelial function. However, little information is available on endothelial function and its determinants in veins. We investigated the association between saphenous vein endothelial function and C-reactive protein levels in patients treated with statins undergoing coronary artery bypass surgery., Methods: Seventy-six patients with optimal low-density lipoprotein cholesterol levels (< or =1.6 mmol/L) secondary to regular treatment with a minimum of simvastatin 40 mg were recruited. Each subject underwent detailed characterization according to anthropomorphic data, saphenous vein endothelial function (assessed ex vivo by measuring acetylcholine-induced relaxation of venous rings), and markers of systemic inflammation (C-reactive protein and tumor necrosis factor-alpha)., Results: Despite regular treatment with statins, 26% of patients had C-reactive protein levels in the "high-risk" range (>3.0 mg/L). There was a negative linear correlation between acetylcholine-induced venous relaxation and C-reactive protein (r = -.30, P = .02) and waist circumference (r = -0.21, P = .03). In a multivariate regression model, C-reactive protein (P = .02) was the only independent predictor of acetylcholine-induced venous relaxation. In turn, correlates of C-reactive protein were assessed. There was a correlation between C-reactive protein and coronary atherosclerotic burden (r = .46, P < .0001), body mass index (r = .26, P = .03), fasting glucose levels (r = .31, P = .01), and waist circumference (r = .29, P = .01). Using multivariate analysis, coronary atherosclerotic burden (P < .0001) was the only independent predictor of C-reactive protein., Conclusions: In our cohort of patients with coronary artery disease, C-reactive protein level was the only independent predictor of saphenous vein endothelial function. In turn, its levels were independently influenced by the extent of coronary atherosclerotic burden.

Aims: We sought to define the mechanisms and correlates of leptin's vascular actions in humans with coronary artery disease., Methods and Results: In 131 patients (age 65.7+/-0.7 years mean+/-SEM), ex vivo vascular reactivity to leptin (10(-13)-10(-7) M) was assessed in saphenous vein (SV) rings. Leptin led to SV relaxation (maximal relaxation 24.5+/-1.6%). In separate experiments, relaxation to leptin was unaffected by L-NMMA (17.4+/-3.4 vs.17.8+/-3.3%, P = 0.9) or endothelial denudation (17.4+/-4.4 vs. 22.5+/-3.0%, P = 0.4). We explored the possibility that leptin's vascular effects are mediated via smooth muscle hyperpolarization. In the presence of KCl (30 mmol/L) to inhibit hyperpolarization, the vasodilator effect of leptin was completely blocked (0.08+/-4.1%, P < 0.001 vs. control). Similar results were demonstrated in internal mammary artery rings. The only independent correlate of leptin-mediated vasodilatation was plasma TNF-alpha (r = 0.25, P < 0.05). Neither body mass index nor waist circumference correlated with leptin-mediated vasorelaxation. This lack of a correlation with markers of total body fat/fat distribution suggests that leptin resistance may not extend to the vasculature., Conclusion: Leptin is a vasoactive peptide in human SV and internal mammary artery. Its action is not nitric oxide or endothelial-dependent. Markers of body fat did not correlate with leptin-mediated vasodilatation, raising the intriguing possibility of selective resistance to leptin's actions.

Background: Bilateral internal thoracic artery (BITA) bypass grafts have advantages over single internal thoracic artery (SITA) bypass grafts in the medium term, particularly in diabetics. However, the perceived higher sternal complication rates seen in diabetics have led many surgeons to avoid the use of BITA surgery. The aim of our study was to assess the validity of this approach by assessing the incidence of sternal infections over a 10-year period in one institution., Methods: A retrospective analysis was made of our coronary artery bypass graft (CABG) patients over a 10-year period (7,581 patients). Nine hundred and twenty-two of the patients were diabetics (261 insulin-dependent diabetes mellitus [IDDM]). Of the insulin-dependent diabetics, 166 had SITA, and 95 had BITA grafts., Results: There was no significant difference in this subgroup in terms of gender, preoperative angina, dyspnea class, left ventricular function, and number of distal anastomoses. Comparing the rates of sternal wound complications of SITA and BITA in IDDM are the following: (1) superficial sternal infection, 6.6% in SITA, 1.1% in BITA (p = 0.04); (2) deep sternal infection, 1.2% in SITA, 3.2% in BITA (p = 0.27); (3) sternal dehiscence, 1.2% in SITA, 3.2% in BITA (p = 0.27)., Conclusions: Our data do not support the perception that BITA grafting increases the risk of sternal complications in insulin-dependent diabetic patients.

Heparin is routinely used for anticoagulation during cardiopulmonary bypass; it is fast acting, is easily monitored, and has an antidote. Heparin-induced thrombocytopenia (HIT) can be a life-threatening condition requiring an alternative anticoagulant (hirudin) if cardiac surgical intervention is considered. At full anticoagulant doses, the effects of hirudin are difficult to monitor; therefore, we present a case in which off-pump coronary artery bypass grafting was performed in an HIT patient in whom the lower doses of hirudin could safely be monitored with easily available tests.

Background: Using algorithms based on point of care coagulation tests can decrease blood loss and blood component transfusion after cardiac surgery. We wished to test the hypothesis that a management algorithm based on near-patient tests would reduce blood loss and blood component use after routine coronary artery surgery with cardiopulmonary bypass when compared with an algorithm based on routine laboratory assays or with clinical judgement., Methods: Patients (n=102) undergoing elective coronary artery surgery with cardiac bypass were randomized into two groups. In the point of care group, the management algorithm was based on information provided by three devices, the Hepcon, thromboelastography and the PFA-100 platelet function analyser. Management in the laboratory test group depended on rapidly available laboratory clotting tests and transfusion of haemostatic blood components only if specific criteria were met. Blood loss and transfusion was compared between these two groups and with a retrospective case-control group (n=108), in which management of bleeding had been according to the clinician's discretion., Results: All three groups had similar median blood losses. The transfusion of packed red blood cells (PRBCs) and blood components was greater in the clinician discretion group (P<0.05) but there was no difference in the transfusion of PRBCs and blood components between the two algorithm-guided groups., Conclusion: Following algorithms based on point of care tests or on structured clinical practice with standard laboratory tests does not decrease blood loss, but reduces the transfusion of PRBCs and blood components after routine cardiac surgery, when compared with clinician discretion. Cardiac surgery services should use transfusion guidelines based on laboratory-guided algorithms, and the possible benefits of point of care testing should be tested against this standard.

Background: Coronary artery bypass grafting with hypothermic cardiac arrest and cardiopulmonary bypass (CPB) is associated with myocardial injury. Our study investigated whether an infusion of glucose, insulin and potassium (GIK) during elective coronary artery bypass surgery decreases myocardial cell death., Methods: We measured cardiac troponin I (cTnI), a myofibrillar structural protein, which is a sensitive and specific indicator of myocytic injury. With ethics committee approval, 42 patients were enrolled into a randomized, prospective, double-blinded study. In the GIK group, 500 ml of 50% dextrose solution containing 100 IU insulin and potassium 80 mmol was infused at the rate of 0.75 ml kg(-1) h(-1). Patients in the non-GIK group received 5% dextrose solution at the same rate. Arterial blood samples were taken before induction of anaesthesia, after removal of the aortic clamp and 6 and 12 h after CPB., Results: In both groups there was an increase in cTnI concentration (P<0.05), which was greatest about 6 h after CPB. At no time did the cTnI concentration differ between the two groups., Conclusion: The results suggest that GIK does not decrease the irreversible myocardial damage associated with routine coronary artery bypass surgery.

The radial artery continues to enjoy resurgence in popularity as a conduit for coronary artery bypass grafting but few studies have examined the prevalence of preexisting disease in this vessel. We highlight a potential, avoidable pitfall when use of the radial artery for coronary artery bypass grafting is proposed.

Background: The internal mammary artery is used widely as a conduit for coronary artery bypass grafting. Most practicing cardiac surgeons are unaware of an aberrant side branch, the lateral costal artery (LCA), that arises proximally. Unligated, this side branch has been held responsible for early recurrence of angina in a small number of patients in the literature. In this study we identified the incidence and length of the LCA., Methods: We studied 103 patients who had coronary artery bypass grafting with bilateral internal mammary arteries. The presence or absence of an LCA was noted, and a record was made of the number of intercostal spaces traversed., Results: Thirty-one of 103 patients had an LCA on one or the other side. Twenty-five patients had bilateral LCAs in which length was equal on both sides in 18. Median length was two intercostal spaces (range, one to six). The LCA extended to the fifth space or beyond in 5 patients., Conclusions: The LCA was present in one third of patients who had coronary artery bypass grafting. A few patients had vessels sizable enough to raise concerns about recurrence of angina. It is prudent to exclude the presence of an LCA in all patients who have cardiac operations.

We present a 45-degree two-stage venous cannula that confers advantage to the surgeon using cardiopulmonary bypass. This cannula exits the mediastinum under the transverse bar of the sternal retractor, leaving the rostral end of the sternal incision free of apparatus. It allows for lifting of the heart with minimal effect on venous return and does not interfere with the radially laid out sutures of an aortic valve replacement using an interrupted suture technique.

The proper management of patients with asymptomatic abdominal aortic aneurysms and significant coexistent coronary artery disease is still debatable. The most common approach has been to perform the coronary artery bypass surgery some weeks before the abdominal aortic aneurysm repair in the hope of reducing the cardiac morbidity and mortality. We report our initial experience of three consecutive elective cases where the coronary artery bypass surgery and the abdominal aortic aneurysm repair were performed at one operation by the same operating surgeon.

Spinal anesthesia recently has gained popularity for elective cesarean section. Our anesthesia service changed from epidural to spinal anesthesia for elective cesarean section in 1991. To evaluate the significance of this change in terms of time management, costs, charges, and complication rates, we retrospectively reviewed the charts of patients who had received epidural (n = 47) or spinal (n = 47) anesthesia for nonemergent cesarean section. Patients who received epidural anesthesia had significantly longer total operating room (OR) times than those who received spinal anesthesia (101 +/- 20 vs 83 +/- 16 min, [mean +/- SD] P < 0.001); this was caused by longer times spent in the OR until surgical incision (46 +/- 11 vs 29 +/- 6 min, P < 0.001). Length of time spent in the postanesthesia recovery unit was similar in both groups. Supplemental intraoperative intravenous (i.v.) analgesics and anxiolytics were required more often in the epidural group (38%) than in the spinal group (17%) (P < 0.05). Complications were noted in six patients with epidural anesthesia and none with spinal anesthesia (P < 0.05). Average per-patient charges were more for the epidural group than for the spinal group. Although direct cost differences between the groups were negligible, there were more substantial indirect costs differences. We conclude that spinal block may provide better and more cost effective anesthesia for uncomplicated, elective cesarean sections.

Thirty-three intraabdominal complications occurred in 27 patients over a 16-year period in 4,629 patients who underwent cardiopulmonary bypass (0.58% incidence). The mortality was 14.8% for the intraabdominal complication group compared with 3.4% for the control group of patients (p less than 0.01). The most common complication was gastrointestinal hemorrhage (n = 20), of which esophagitis (n = 6) was the most common cause. However, patients with duodenal ulcer (n = 4) had the highest mortality; 2 patients who underwent truncal vagotomy and pyloroplasty subsequently died. Two further patients underwent operation for perforated anterior duodenal ulcers without further morbidity. Cholecystitis developed in 5 patients and acute pancreatitis in 4; all were managed nonoperatively with no mortality. Multisystem organ failure developed in 2 patients, of whom 1 died. There was a significant correlation between intraabdominal complications and prolonged bypass time. The mean bypass time was 96.7 +/- 28.6 minutes for the patients with gastrointestinal complications, compared with 81.7 +/- 48.4 minutes for the whole group (p less than 0.01). No correlation was demonstrated for type of operation undergone or the age of the patient. In the last 5 years, 2,145 patients underwent cardiopulmonary bypass, of whom 562 received pulsatile and 1,583 nonpulsatile flow. The incidence of intraabdominal complications was 0.18% (n = 1) in the pulsatile group compared with 0.63% (n = 10) for the nonpulsatile group (p = 0.14). Intraabdominal complications, although of low incidence, carry a significantly high mortality, and the clinician must be alert in the postoperative period to institute early therapy.

We investigated the degree and time course of neutrophil sequestration into human lungs during cardiac operations. At the same time, measurement of the concentration of peroxidation products in the plasma was used as an index of oxidant free radical activity. The study was performed in two groups of patients. Group A (n = 11) had studies extending over the entire operative period and showed a highly significant sequestration of neutrophils into the lung, together with a highly significant (p less than 0.001) rise in peroxidation products from 2.8 +/- 0.12 nmol/ml(mean +/- standard error of the mean)before bypass to a peak of 5.05 +/- 0.13 nmol/ml at the end of bypass. As these changes occurred only during the time after release of the aortic cross-clamp, we investigated this period in more detail in a second group of patients (Group B, n = 7). Results from this group showed that significant release of peroxidation products occurred at the same time as pulmonary neutrophil sequestration. This study has produced evidence of increased oxidant activity in the lung associated with cardiac operations. Nevertheless, it is not known whether the neutrophils sequestered into the lung alone induced the increased activity. Similarly, whether neutrophil-derived oxidant species are the sole cause of lung tissue injury remains unproved.