Usefulness of the axillary artery as vascular access for cardiopulmonary bypass.

AIM: In this paper we report our clinical experience with extended utilization of axillary artery cannulation for cardiopulmonary bypass (CPB) and discuss the indications and the results of the procedure in terms of complications and usefulness. METHODS: Between January 1999 and May 2004, 26 patients underwent right axillary artery cannulation for CPB. Fifteen patients presented acute type A aortic dissection and were operated urgently. Axillary cannulation was also used in 11 elective cases: 3 reoperative coronary surgery, 3 valve redo-operations and 5 cases of aortic valve regurgitation+aneurysm of the ascending aorta. RESULTS: All axillary artery cannulations were successful (21 direct and 5 with a side graft) without neurologic or vascular injuries to the right upper extremities. Hospital mortality was 7.7% and included 2 patients operated in an emergency procedure because of acute type A aortic dissection. In all cases, this cannulation site provided adequate perfusion, with a range of peak flows from 4.1 to 5.7 L/min. CONCLUSION: Our preliminary results demonstrate that the right axillary artery may be considered an alternative cannulation site for achieving full CPB and providing antegrade flow, thus avoiding complications related to retrograde flow when femoral artery perfusion is performed. This safe and useful method may be used not only in aortic surgery but in other such complex cardiac procedures as redo-operations.

Neutrophil-endothelial cells modulation in diabetic patients undergoing coronary artery bypass grafting.

OBJECTIVE: Diabetes mellitus is a well-known risk factor in patients undergoing coronary artery bypass grafting. Myocardial and pulmonary injury often occurs after cardiopulmonary bypass (CPB), mediated in part by neutrophil activation and adhesion to endothelial cells. The objectives of the present study are to compare the degree of neutrophil activation and neutrophil-endothelial cells adhesive interactions in diabetic patients after CPB. METHODS: Nitro-blu tetrazolium scores, CD 11b expression and neutrophil-endothelial cells adhesion were assessed in blood samples from 15 diabetic and 15 control patients who had undergone elective coronary bypass grafting. Blood samples were obtained at baseline, 30 min after beginning CPB, at the end of CPB and 60 min postoperatively. At the same sampling points as above, blood glucose levels were also checked in all patients. RESULTS: Diabetes was associated with a significant basal increase in neutrophil CD1 lb expression and adhesion to endothelial cells as well as with an increased superoxide anion production. The increased adhesion of diabetic neutrophils persisted by the end of the CPB to 60 min postoperatively independently of the blood glucose levels. Antibodies directed against CD1 lb and CD18 significantly reduced the degree of neutrophil adhesion observed 60 min postoperatively. CONCLUSIONS: These results indicate that diabetes mellitus is associated with an increased neutrophil-endothelial cell adhesion probably mediated by the CD1 1b/CD18 molecule; this, in turn, might be responsible for the increased risk of postoperative complications observed in diabetic patients undergoing coronary artery bypass grafting.

Nitric oxide inhibits neutrophil adhesion during experimental extracorporeal circulation.

BACKGROUND: Myocardial and pulmonary injuries often occur after cardiopulmonary bypass, mediated in part by neutrophil activation and adhesion to endothelial cells. The effects of nitric oxide (NO) administration on neutrophil adhesion to endothelial cells after simulated extracorporeal circulation were investigated. METHODS: Two identical extracorporeal circulation circuits were primed with fresh human blood and circulated for 2 h at 37 degrees C. Nitric oxide at a 40-ppm concentration was added to one of the oxygenators in each pair. Neutrophil CD11b/CD18 expression and their adhesion to human umbilical vein endothelial cell monolayers were assayed in leukocytes isolated from samples drawn from the circuit 30, 60, 90, and 120 min after circulation began. In another series of experiments, blocking monoclonal antibodies to both neutrophil CD11b and CD18 were incubated with polymorphonuclear leukocytes after removal from the circuit before the adhesion assay. RESULTS: After 60 min of circulation, the neutrophils from NO-treated circuits showed significantly reduced CD11b/CD18 surface expression compared with the control group. There was also a significant reduction in neutrophil-endothelial adhesion in the NO group after 120 min of circulation. Monoclonal antibodies to both CD11b and CD18 significantly inhibited the adhesion of polymorphonuclear leukocytes at endothelial cells after 120 min of circulation. CONCLUSIONS: These results confirm that neutrophil activation occurs during cardiopulmonary bypass. The addition of NO to the circuits of extracorporeal circulation significantly affects neutrophil adhesion to endothelial cells.

Protection by coenzyme Q10 of tissue reperfusion injury during abdominal aortic cross-clamping.

PURPOSE: To evaluate the effect of coenzyme Q10 in reducing the skeletal muscle reperfusion injury following clamping and declamping the abdominal aorta. METHODS: 30 patients undergoing elective vascular surgery for abdominal aortic aneurysm or obstructive aorto-iliac disease were randomly divided into two groups: patients in group I were treated with coenzyme Q10 (150 mg/day) for seven days before operation, and those in group II received a placebo. We studied the hemodynamic profile in each patient during clamping and declamping of the abdominal aorta. The plasma concentrations of thiobarbituric acid reactive substances (malondialdhehyde), conjugated dienes, creatine kinase and lactate dehydrogenase were measured in samples from both arterial and inferior vena cava sites. Serial sampling was performed after induction of anesthesia, 5 and 30 minutes after abdominal aortic cross clamping, 5 and 30 minutes after aortic cross-clamp removal. RESULTS: The concentrations of malondialdehyde, conjugated dienes, creatine kinase and lactate dehydrogenase in patients who received CoQ10 were significantly lower than in the placebo group. Decrease of plasma malondialdehyde concentrations correlated positively (p < 0.01) with decrease of both creatine kinase and lactate dehydrogenase release in samples from the inferior vena cava. The hemodynamic profile during clamping and declamping the abdominal aorta was similar in both groups. CONCLUSIONS: Our findings suggest that pre-treatment with coenzyme Q10 may play a protective role during routine vascular procedures requiring abdominal aortic cross clamping by attenuating the degree of peroxidative damage.

Pericardial cyst with partial erosion of the superior vena cava. An unusual case.

A case of pericardial cyst with partial erosion of the superior vena cava occasionally discovered is presented. The involvement of the vein was found on operation and the excision of the cyst was performed without cardiopulmonary bypass, repairing the vena cava by a direct suture. The pathologic examination showed multiple areas of acute and chronic inflammation without signs of infection. This exceedingly rare report indicates that both computed tomography and magnetic resonance are useful to localize the mediastinal mass and to characterize the cystic content. The cardiopulmonary bypass must be available to allow an easy repair of the structures possibly involved particularly in the case of infection.

Changes in the proportion of types I and III collagen in the left ventricular wall of patients with post-irradiative pericarditis.

Pericardiectomy for post-irradiative constrictive pericarditis achieves poor results because of the extensive damage to the heart and pericardium caused by ionizing radiation. The extracellular structural protein, collagen, is responsible for the functional integrity of the myocardium and allows reversible interdigitation and the transmission of force between contracting myocytes. Collagen concentration and composition were examined in the cardiac tissue of three patients undergoing pericardiectomy and post-irradiative pericarditis. Normal heart tissue was taken at autopsy from patients without cardiac disease and acted as controls. Total collagen concentration (mean(s.e.m.)) was significantly increased in the ventricular tissue of patients with post-irradiative pericarditis compared with that of the controls (119.8(16.6) versus 50.4(5.2) mg/g dry weight, P<0.01). Although there was an increase in concentration of both type I and III collagen, a disproportional increase in type I was observed. The proportion of type III collagen was lower in patients with post-irradiative pericarditis than in the control group (33(2.6)% versus 38.2(3.7)%, P<0.05). The results of the present study suggest that this marked alteration in collagen concentration and proportion may contribute to the impaired diastolic distensibility of the ventricles seen in this group of patients.

Reduction by indobufen of neutrophil activation in peripheral arterial occlusive disease.

We evaluated the effectiveness of indobufen administration in reducing neutrophil activation in a clinical model of ischemia-reperfusion. Thirty stable patients with intermittent claudication due to occlusive peripheral arterial disease of the leg were randomly assigned to two groups. Patients in group I were treated with indobufen [200 mg orally twice daily (p.o. b.i.d.) for a week]; patients in group II received a placebo. Both groups of patients were submitted to standardized treadmill exercise until onset of claudication. Plasma levels of thromboxane B2 (TxB2) and 6-keto-prostaglandin F1alpha(6-k-PGF1alpha) neutrophil filterability, and neutrophil activation (by nitro-blue tetrazolium test) were assessed in blood samples from the femoral vein draining the ischemic leg. The values were obtained at rest and 5, 30, and 60 min after onset of claudication. Urinary albumin excretion was measured at rest and 1 h after onset of claudication. Plasma levels of TxB2 and 6-k-PGF1alpha increased significantly in the placebo group 5 min after onset of claudication, whereas only a slight nonsignificant increase was observed in the indobufen-treated group at the same timepoint.

Collagen network remodelling and left ventricular function in constrictive pericarditis.

OBJECTIVE: To investigate whether patients with constrictive pericarditis have changes in collagen content and architecture that could influence left ventricular function. DESIGN: Cohort study. SETTING: University teaching hospital. PATIENTS: Biopsy specimens of myocardium from 13 patients admitted consecutively for treatment of chronic constrictive pericarditis were compared with normal heart tissue taken at necropsy from 15 patients free of cardiac disease. INTERVENTION: Pericardiectomy through median sternotomy. Biopsy specimens (4 or 5) were taken from the left ventricular free wall. MAIN OUTCOME MEASURES: Biochemical and histological assessment of total collagen content, relative proportion of type I and III collagen, and amount of orthogonal collagen fibre meshwork (crosshatching) in the left ventricular tissue. RESULTS: There was more collagen in the myocardium of patients with constrictive pericarditis than in controls when measured either biochemically by hydroxyproline content (89.4 v 50.4 mg/g dry weight) or by histological measurement of the collagen fraction of the myocardium (2.4% v 7.0%). Neither of these measurements, however, correlated with left ventricular ejection fraction, pulmonary wedge pressure, or right ventricular end diastolic pressure. The thickness of the fibrous trabeculae in the myocardium was, however, inversely related to both left ventricular ejection fraction (r = -0.76) and deceleration time (r = -0.68). Trabecular thickening was also related to NYHA class, with those in class III and IV having the greatest thickening. CONCLUSION: Changes in collagen content and architecture may contribute to impaired ventricular function in patients with chronic constrictive pericarditis.

Improved beta-adrenergic receptor function after coronary artery bypass grafting in patients with congestive heart failure.

BACKGROUND: To evaluate whether coronary artery bypass grafting (CABG) in patients with congestive heart failure (CHF) modifies beta-adrenergic receptor dysfunction, we measured lymphocytic beta-adrenergic receptor density and function, and plasma catecholamine levels in patients with congestive ischaemic disease scheduled for CABG. METHODS: Assays were performed on 20 patients with CHF at admission and 6 months following CABG; 20 age-matched healthy subjects served as the control group. RESULTS: Preoperative lymphocyte beta-adrenergic receptor density was significantly reduced in patients with CHF compared with the control group. Similarly, basal adenylyl cyclase as well isoproterenol- and NaF-stimulated adenylyl cyclase activity was significantly reduced in lymphocytic membranes of patients with CHF compared with controls. Conversely, no difference was found in forskolin-stimulated adenylyl cyclase activity between the two groups of patients. Preoperatively, plasma levels of both noradrenaline and adrenaline were significantly higher in patients with CHF compared with the control group. CABG was associated with clinical and haemodynamic improvement in all patients. Lymphocyte beta-adrenergic receptor density and function were also improved. Basal beta-adrenergic receptor density improved from 39.2 +/- 1.7 to 46 +/- 1.5 fmol/mg protein. Basal adenylyl cyclase activity increased from 33.1 +/- 2.6 40 +/- 2.4 pmol/mg protein per min; a significant increase in activity stimulated by isoproterenol (from 41.5 +/- 3.1 to 61 +/- 3.8 pmol/mg protein per min) and by NaF (from 71.8 +/- 2.7 to 85.3 +/- 3.5 pmol/mg protein per min) was also observed. Although postoperative plasma catecholamine levels tended to decrease, the difference compared with preoperative values was not significant. CONCLUSION: The results of our study indicate that CABG in patients with CHF is accompanied by the restoration of an almost normal functional state of the lymphocytic beta-adrenergic receptor system.

Suppressed fibrinolysis after administration of low-dose aprotinin: reduced level of plasmin-alpha2-plasmin inhibitor complexes and postoperative blood loss.

Various clinical investigation have shown that aprotinin therapy reduces bleeding after open-heart operations. In this study low-dose aprotinin, 30,000 KIU/kg in the cardiopulmonary bypass (CPB) priming volume and 7,500 KIU/kg intravenously each hour during CPB, was used in ten patients undergoing primary myocardial revascularization or surgery for valvular diseases. Another ten patients served as controls. Blood loss, platelet count and plasma levels of hemoglobin, antithrombin III, fibrinogen, fibrinogen degradation products (FDP), total plasmin inhibitor and alpha2-plasmin inhibitor-plasmin complexes were evaluated at nine preoperative, intraoperative and postoperative points. Intraoperative and postoperative blood loss was significantly reduced in the aprotinin group. There was no significant difference between the two groups in platelet count and levels of hemoglobin and antithrombin III. A significant increase in FDP during CPB in the control group indicated hyperfibrinolysis. The levels of plasmin inhibitor were significantly reduced during CPB in the control group. The alpha 2-plasmin inhibitor-plasma complex levels, indicating the plasmin activity, were significantly reduced in the aprotinin group. These results confirmed that low-dose aprotinin reduced blood loss with the prevention of hyperfibrinolysis during CPB and demonstrated improved hemostasis.

Combined mitral valve prolapse and atrial septal aneurysm. A cause for embolic events.

The "association" atrial septal aneurysm and mitral valve prolapse is often asymptomatic with an incidence of about 1% in autopsied adults. Occasionally, however, embolic phenomena can occur. The two-dimensional echocardiography allows an accurate diagnosis of these two cardiac lesions when present. In this paper the Authors report on three patients affected by mitral valve prolapse associated with atrial septal aneurysm, one of whom complicated by a cerebral embolism. Owing to the significant incidence of peripheral or cerebral vascular embolic events in this group of patients, the Authors conclude that long-term anticoagulation therapy is mandatory in all cases, whereas a surgical repair could be advisable when a previous embolism or interatrial shunting is demonstrated.

Protection by coenzyme Q10 from myocardial reperfusion injury during coronary artery bypass grafting.

To evaluate the effect of coenzyme Q10 in reducing postoperative cardiac complications after ischemia and reperfusion, we randomly divided 40 patients undergoing elective coronary artery bypass into two groups: patients in group 1 received coenzyme Q10 (150 mg/day) for 7 days before operation, and those in group 2 were the control group. Concentrations of thiobarbituric acid-reactive substances (malondialdehyde), conjugated dienes, and cardiac isoenzymes of creatine kinase were measured in samples from both arterial and coronary sinus sites. Serial sampling was performed 5 minutes after heparin administration, at 10 and 30 minutes during cardiopulmonary bypass, 15 and 30 minutes after aortic cross-clamp removal, and 5 minutes after protamine administration. The concentrations of malondialdehyde, conjugated dienes, and creatine kinase in group 1 were significantly lower than those in group 2. The decrease in plasma malondialdehyde concentrations correlated positively with the decrease in creatine kinase levels in the coronary sinus. The treatment group showed a significantly lower incidence of ventricular arrhythmias during the recovery period than did the control group (p < 0.05). Although the percentage of patients requiring inotropic agents was not significantly different between the two groups, the mean dosage of dopamine required to maintain stable hemodynamics was significantly lower in patients of group 1 than in those of group 2 (p < 0.01). Our findings suggest that pretreatment with coenzyme Q10 may play a protective role during routine bypass grafting by attenuating the degree of peroxidative damage.

Primary malignant melanoma of the oesophagus with a left atrial metastasis.

A 75 year old man with an eight month history of dysphagia and weight loss underwent pericardiocentesis for a massive pericardial effusion. The echocardiogram showed a mass in the left atrium, and computed tomography also showed distal oesophageal narrowing, which was found to be due to a malignant melanoma. The left atrial mass, investigated by immunoscintigraphy with technetium-99m labelled monoclonal antibody, was diagnosed as metastatic melanoma. This represents a rare case of primary oesophageal melanoma with left atrial metastasis.

Thermographic evaluation of myocardial cooling and intraoperative control of graft patency in patients with coronary artery disease.

Intraoperative thermographic evaluation of regional myocardial cooling induced by cardioplegia, in patients with coronary artery disease, was conducted in 22 cases. Pictures were obtained at the beginning of the cardiopulmonary by-pass, after general cooling and during cardioplegic infusion. Uneven myocardial cooling was observed related to the degree of coronary artery stenosis. After the distal anastomosis of the saphenous vein by-pass graft was completed, injection of cold solution in to the graft showed marked cooling of the dependent myocardium, proving the patency of the graft. In the case of internal mammary artery graft (IMA), after the anastomosis was completed, releasing the bull-dog clamp on the IMA graft, allowed a flow of relatively warm (30 degrees C) blood in the anterolateral wall of the cold (20 degrees C) heart. A warm spot appeared in the thermographic pictures, assessing the patency of the IMA graft. Thermography appears to be a useful tool during myocardial revascularization in order to assess proper myocardial cooling during cardioplegia, and to check intraoperative patency of saphenous vein graft and IMA graft. The use of a special mirror prevents interference with the surgeon's work.