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Background: Evidence suggests that cardiac output-guided haemodynamic therapy algorithms improve outcomes after high-risk surgery, but there is some concern that this could promote acute myocardial injury. We evaluated the incidence of myocardial injury in a perioperative goal-directed therapy trial., Methods: Patients undergoing major gastrointestinal surgery (n=723) were randomly assigned to cardiac output-guided haemodynamic therapy (intervention group) or usual care as part of the OPTIMISE trial. At four participating sites, 288 patients were enrolled in a biomarker substudy. Serum high-sensitivity cardiac troponin I (TnI) concentration and N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration were measured before and at 24 and 72 h after surgery., Results: Median preoperative TnI and NT-ProBNP concentrations were 4.3 ng litre(-1) and 144 pg ml(-1), respectively. After surgery, 67 (46%) patients in the intervention group and 68 (48%) patients receiving usual care had TnI concentrations above the 99th centile upper reference limit (P=0.82). Peak serum TnI concentration was similar in the intervention and usual care groups (median [interquartile range]: 10.0 [5.3-21.5] vs 7.8 [5.0-21.8] ng litre(-1); P=0.85), and no differences were observed in serum TnI concentrations over 72 h (repeated-measures anova, P=0.51). Likewise, there were no differences in peak NT-proBNP concentration between intervention and usual care groups (645 [362-1169] vs 659 [381-1028] pg ml(-1); P=0.86) or in serial NT-proBNP concentrations over 72 h (P=0.20)., Conclusions: Myocardial injury is common among patients undergoing major gastrointestinal surgery. In this study, the frequency was not affected by cardiac output-guided fluid and low-dose inotropic therapy., (© The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Objective: Pregnancy is associated with marked changes in vascular physiology and an increased risk of thrombosis. The aim of the study was to assess the effect of pregnancy on the acute release of tissue plasminogen activator (t-PA) from the endothelium., Methods and Results: Ten primigravida pregnant women were recruited in the third trimester of pregnancy (week 36 +/- 1) and compared with 20 age-matched non-pregnant women (day 9.8 +/- 0.3 of menstrual cycle). Blood flow and plasma fibrinolytic factors were measured in both forearms by venous occlusion plethysmography and blood sampling, respectively, during unilateral brachial artery infusions of bradykinin (100-1000 pmol min(-1)). Pregnant women had higher plasma plasminogen activator inhibitor type 1 (PAI-1) antigen concentrations (77.1 +/- 12.4 vs. 21.5 +/- 9.8 ng mL(-1); P = 0.004) that resulted in lower basal t-PA/PAI-1 ratios (0.2 +/- 0.1 vs. 0.6 +/- 0.1; P = 0.02) and plasma t-PA activity concentrations (0.17 +/- 0.02 vs. 0.58 +/- 0.06 IU mL(-1); P < 0.0004). In both groups, bradykinin caused dose-dependent increases in blood flow and local release of plasma t-PA antigen and activity (P < 0.005 for all). Both the plasma t-PA/PAI-1 ratios and the net release of active t-PA were markedly reduced in pregnant women (P < 0.05 for both). Area under the curve for net active t-PA release was reduced by 36%., Conclusions: Pregnancy is associated with major perturbations of endogenous fibrinolytic capacity with an overwhelming increase in plasma PAI-1 concentrations and an inadequate release of active t-PA. These prothrombotic effects may, in part, explain the increased risk of arterial and venous thrombosis in pregnant women.

Background: Nonischemic myocardial dysfunction in patients with diabetes mellitus appears to be attenuated with long-term L-carnitine therapy. The effect of acute L-carnitine supplementation on rat hearts from euglycemic and diabetic animals subjected to ischemia and reperfusion is investigated in this study., Methods: Study rats had diabetes mellitus induced by streptozocin (65 mg/kg intraperitoneally), and control rats had injection of saline solution (n = 12 per group). About 1 month later, the hearts were suspended on a Langendorff apparatus and perfused with either standard buffered Krebs-Henseleit solution or this standard solution supplemented with L-carnitine (5 mmol/L). After stabilization, normothermic, zero-flow ischemia was instituted for 20 minutes followed by 60 minutes of reperfusion. There were four study groups (n = 6 per group): hearts that were from euglycemic rats and that were perfused with standard buffered Krebs-Henseleit solution (E-STD); hearts that were from diabetic animals and that were perfused with the same standard buffered solution (DM-STD); hearts taken from diabetic animals and perfused with L-carnitine-enriched solution (DM-CAR); and hearts taken from euglycemic rats and perfused with the enriched solution (E-CAR)., Results: At 60 minutes of reperfusion, left ventricular developed pressure was significantly better in hearts from both groups (diabetic and euglycemic) with carnitine supplementation (DM-CAR versus DM-STD and E-CAR versus E-STD, p < 0.01 for both, by analysis of variance). Left ventricular end-diastolic pressure was significantly lower in the DM-CAR group compared with all other groups (p < 0.01 by analysis of variance)., Conclusions: These findings suggest that acute L-carnitine supplementation significantly improves the recovery of the ischemic myocardium in diabetic and euglycemic rats.

Background: The Perma-Flow prosthetic coronary graft is a 5-mm polytetrafluoroethylene tube into which is incorporated a Venturi flow restrictor. An aorto-superior vena caval fistula is created and coronary anastomoses are constructed proximal to the resistor in side-to-side fashion, where arterial pressure is maintained. From November 1992 through December 1995, eight investigational centers in North America have implanted this graft in 40 patients with inadequate autologous alternatives., Methods: Patients were selected for inclusion in this study if coronary artery bypass grafting was required and adequate autologous conduit to complete revascularization was not available. Operative data were completed by the implantating surgeon and referred to a central center, the Minneapolis Heart Institute, for correlation. Follow-up was conducted by data coordinators at each institution, and follow-up data were obtained directly from these coordinators for inclusion in the study., Results: Patient age ranged from 53 to 82 years, and 15 patients were undergoing reoperations (38%). On each Perma-Flow graft one to four coronary side-to-side anastomoses were constructed. In addition, left internal mammary artery (n = 26), greater saphenous vein (8), right internal mammary artery (4), and gastroepiploic artery (4) were used to complete revascularization. Aortic (2) or mitral valve replacement (1) was also carried out. There were seven operative deaths (18%) and two late deaths (4 and 6 months). After 1 to 37 months (mean, 13 +/- 9 months) of follow-up, 29 of 31 surviving patients are asymptomatic. Echocardiographic heart size has not increased from the postoperative value, indicating limited volume load has not affected heart size. Protocol catheterization (n = 32) in 28 patients 1 week to 1 year postoperatively revealed 7 of 73 studied coronary anastomoses (9.5%) and two distal extensions and resistors were occluded (7%). In 1 patient during sternal debridement at 1 year, no flow was found in the graft., Conclusions: The Perma-Flow graft is a useful adjunct to complete revascularization in patients with deficient autologous conduit.

Background: Widely separated coronary arteries with significantly diseased tissue continues to challenge surgeons repairing ascending aortic aneurysms., Methods: Occasional troublesome leaks around coronary ostial anastomoses and Cabrol graft thrombosis prompted a change of our operative management of this condition. Collagen-impregnated 8-mm "legs" grafts are used to connect the coronary arteries to the composite graft. Ten patients, aged 14 to 70 years, underwent the operation., Results: The first patient is 15 years after the operation and is symptom free. One patient died of an arrhythmia 1 month after discharge. Eight patients are living and well 11/2 to 4 years postoperatively., Conclusions: Advantages of direct interposition (legs) grafts are as follows: the coronary arteries are separately perfused and the risk of catastrophic thrombosis from a longer high-volume graft is eliminated. Problems with coronary ostial mobilization are avoided. The technique allows full visualization and hemostatic suture line testing with cardioplegia before aortic declamping. Space constraints with reoperations are easily managed, whereas other techniques may result in graft compression on refilling of the heart and termination of bypass. The technique is carried out with ease and reproducibility, and the availability of new graft material has made it our treatment of choice for ascending aortic composite graft replacement.

This paper describes our experience in performing saphenous vein bypass grafts to the circumflex coronary artery system with a left thoracotomy in 9 patients. Illustrative case reports demonstrate the spectrum of patients for whom this approach has been useful. The advantage of this technique is that it allows the surgeon to avoid the adhesions that make a redo sternotomy time-consuming and potentially dangerous when previously patent saphenous vein or internal mammary grafts are present. It is particularly useful for patients requiring grafting to the circumflex coronary artery system, especially if the patient is in relatively unstable condition and would benefit from rapid institution of cardiopulmonary bypass. The technique generally employs cannulation of the descending thoracic aorta for arterial inflow and of the main pulmonary artery for venous return. Usually the proximal end of the graft is easily placed to the left subclavian artery. Coronary anastomosis is performed on the cold (15 degrees C), fibrillating heart, and aortic cross-clamping and cardioplegic arrest have not been necessary. Venting is possible through the left atrial appendage should any rise in filling pressures occur. Saphenous vein or internal mammary artery may be used. All patients undergoing this technique have had expeditious discharge from the hospital and excellent relief of symptoms. The technique is an alternative to median sternotomy for properly selected patients.

The resulting abnormal geometry after surgical treatment of left ventricular aneurysm has concerned a number of surgeons since the first successful repair in 1958, but little attention was placed on the altered geometry until attempts were made to effect a more physiologic aneurysmorrhaphy in 1973. Substantial attention was focused on a concept of geometric reconstruction from within the left ventricle in 1985. A prosthetic patch was employed with the concept to redirect normal muscle bundles to their original orientation and position. Further refinements include use of improved materials for the repair, preservation and bypass of the left anterior descending coronary artery, ablation of ventricular arrhythmias when indicated, and the absence of prosthetic material used in contact with the pericardial surface. Our experience with repair of 61 left ventricular aneurysms at West Jefferson Medical Center over a 4 1/2-year period with a 3.3% mortality rate has prompted a change from the standard linear repair to routine use of a modified endoventricular repair. Currently, the low surgical risk due to advances in left ventricular aneurysmorrhaphy combined with the knowledge that contractile areas will progressively deteriorate in ventricles stressed by poor hemodynamics and with data showing improved left ventricular function postoperatively have led to more liberal recommendations for early left ventricular aneurysm repair.

A search for a coronary bypass conduit with increased longevity has resulted in harvest of the inferior epigastric artery. The artery is dissected through a paramedian incision with retraction of the rectus muscle to the lateral side. As the inferior epigastric artery courses superiorly, it may lie in one of three positions in relation to the rectus muscle. Distal coronary anastomoses using this conduit are conventional, and the proximal anastomosis may be made to the aorta or end-to-side to an internal mammary artery or venous conduit. After preparation with dilute papaverine-Plasmalyte solution proximal sizes have ranged from 2.5 to 3.25 mm (internal diameter), and distal inferior epigastric artery sizes measured 1.5 to 2.5 mm (internal diameter). The lengths of the conduit ranged from 11.5 to 17.0 cm. Eighteen patients aged 41 to 74 years had inferior epigastric artery grafts to 19 coronary arteries. The indications for use were absent or poor-quality vein, young age with an attempt to limit vein graft, and avoidance of use of bilateral internal mammary artery grafts in insulin-dependent diabetic patients. There was one sterile wound hematoma and one late wound infection. There were no other infections and no deaths. Three patients studied postoperatively revealed widely patent inferior epigastric artery grafts.

This prospective study involves 406 consecutive adults who had heart operation with extracorporeal circulation. Fifteen patients (3.7%) bled at the rate of 200 ml per hour or more in the postoperative period. Thirteen of the 15 patients who bled had undergone coronary artery operation. After all clotting factors and, when applicable, hypertension had been checked and corrected, positive end-expiratory pressure (PEEP) was used in managing the bleeding of these patients. Before institution of PEEP, the average bleeding was 330 ml per hour for one to five hours. After PEEP was instituted in the 11 patients in whom bleeding was controlled, an average output of 25 ml per hour for one to ten hours was recorded. Patients were kept on PEEP for 5 to ten hours. In 7 patients hemorrhage was controlled with 10 cm H2O of PEEP; 4 required 15 cm of PEEP to stop bleeding; 3 were explored for continuous bleeding on 15 cm of PEEP; and 1 was explored because of hypotension on 15 cm of PEEP. In 11 of the 15 patients who bled postoperatively (73%), operation was avoided by judicious use of PEEP. We believe that PEEP increases mediastinal pressure and that the overdistended lung can obliterate some bleeding in the mediastinum, thus controlling bleeding in many of these patients.

Seventeen patients 1 day to 28 months old with congenital cyanotic heart disease underwent a modification of the Blalock-Taussig shunt. Eight were newborn infants weighing 2.6 to 4.8 kg. All infants had complex congenital heart defects that were not considered amenable to early correction. There were no early deaths and no shunt failures. Postoperative complications were restricted to prolonged intubation in 2 patients and a subcutaneous wound infection in a 14-day-old infant. Follow-up from 1 to 31 months revealed minimal cyanosis, stable hemoglobin levels, and good shunt murmurs, and there have been no upper extremity complications. There were 2 late deaths; 1 (the oldest patient) was related to medication, and the second resulted from small bowel necrosis. The concept of the azygos vein patch modified Blalock-Taussig shunt involves two factors: (1) mobilizing as much length as possible of the subclavian artery in spite of its distal small size to allow for a tension-free shunt to prevent tension on the anastomosis as growth occurs, and (2) enlarging the subclavian artery distal to the vertebral artery origin with an autologous azygos patch. During performance of a standard Blalock-Taussig shunt, a longitudinal incision is made through the pulmonary artery across the anastomosis into the upper subclavian artery. The appropriate length of harvested azygos vein is used as a patch angioplasty across the shunt. A tension-free shunt with a patulous distal portion is achieved. Pulmonary overcirculation is avoided by the limiting size of the proximal subclavian artery. Temporary occlusion of the shunt at operation resulted in an increased mean blood pressure from 6 to 18% in all infants.(ABSTRACT TRUNCATED AT 250 WORDS)

Pulmonary hamartomas are tumors that occur in the parenchyma or the bronchi. Through the lesions themselves are benign, they may be associated with malignant neoplasms or they may cause obstruction of the bronchi because of their location. Pulmonary hamartomas were resected in 29 patients at the Ochsner Medical Institutions during a 30-year period. Of these patients, 6 had symptoms related to concomitant malignancy and 3 had symptoms resulting from obstruction of the bronchi by the hamartoma. Surgical treatment ranged from enucleation to pneumonectomy. One patient died in the hospital of extensive bronchogenic carcinoma. In 2 others, carcinoma of the lung developed within twelve months after resection of a hamartoma. In this group of patients, 20% had concomitant or subsequent pulmonary lesions. Ten percent of the hamartomas were located in the bronchi, resulting in bronchial obstruction. A surgical approach is indicated for lesions that appear to be pulmonary hamartomas on roentgenograms.

Experience with 39 patients (32 men, 7 women) undergoing coronary artery bypass grafting with the right gastroepiploic artery (RGEA) is reported. Indications initially included poor-quality or absent saphenous vein, ascending aortic atherosclerosis, and repeat coronary artery bypass grafting. The average number of grafts per patient was 4.10. Arteries bypassed were the posterior descending (22 patients), right coronary (12), diagonal (5), and marginal (4). Distal RGEA internal diameters of all grafts measured 1.5 to 3.25 mm (average diameter, 2.14 mm). Pedicled graft lengths measured 18 to 30 cm (average length, 23.7 cm), and free grafts, 8 to 24 cm (average length, 17.7 cm). In 6 patients, no vein grafts were used, and in all patients, at least one internal mammary artery graft was placed. Early postoperative cardiac catheterization (19 pedicled and ten free grafts) in 29 patients revealed all grafts to be patent without a kink or twist, but three of these free RGEA grafts had vasospasm. Advantages of RGEA grafts are as follows: (1) it is a third arterial conduit with artery-artery anastomoses of comparable sizes; (2) a shorter leg incision or no leg incision is necessary; (3) it can be harvested simultaneously with the internal mammary artery and the saphenous vein; (4) the proximal anastomosis (free grafts) is easy; (5) its use avoids bilateral internal mammary artery grafts in patients at high risk for sternal infection; and (6) atherosclerotic ascending aortas are not clamped. Subintimal hyperplasia and atherosclerosis of RGEA grafts are unlikely.(ABSTRACT TRUNCATED AT 250 WORDS)

A study was made of 100 patients who had undergone internal mammary artery myocardial implantation 7 to 10 years previously. Forty-two patients had single implantation with or without a free omental graft, and 54 received double implantations. Four patients had a single internal mammary artery implant plus a single aortocoronary bypass graft. Eleven patients died at operation or within the first month, and 17 died from 1 to 7 years following operation. Two were lost to follow-up, and 15 refused follow-up angiograms. From 7 to 10 years postoperatively, angiographic studies were performed on 55 patients with 73 internal mammary artery implants. Of these 73 implants, 17 (23%) were occluded; 10 (14%) were patent but did not show myocardial filling; 15 (21%) showed myocardial blush or filling of small vessels; and 31 (42%) showed filling of a major coronary artery. The patency rate correlated well with the amount of coronary disease and slightly with the amount of symptomatic improvement. This study shows that the Vineberg operation is physiologically sound; however, the ideal candidates are those patients with coronary arteries of adequate size who could benefit more by direct perfusion.

From 1968 through 1982, 129 homologous vein grafts were used in 91 patients in the following positions: 75 in the femoropopliteal, tibial, or peroneal artery; 38 in the aortocoronary artery; 13 in the aortopulmonary artery; and one each in the atrioventricular fistula, carotid-subclavian artery, and brachial-radial artery. In the lower extremity patency ranged from 0 to 121 months (mean 22.4 +/- 4.4 months). All grafts were performed for limb salvage, and 75% of the patients had undergone previous operations. Cumulative patency by the life-table method showed that while 50% of grafts occluded by 1 year, 60% of the remaining grafts continued to be functional for more than 5 years. Fifty percent of the aortocoronary bypass grafts studied were occluded at 1 year. Eight of the 13 systemic pulmonary artery shunts were patent at time of death, revision, or total correction. Multiple revisions and thrombectomies are required to maintain patency of homograft veins. The outcome is variable and unpredictable. The inconsistency is due to the antigenicity of the graft. If one is committed to the necessary efforts required to ensure long-term patency, the homologous saphenous vein is a suitable substitute when autogenous tissue is unavailable.

The safety of combined operative procedures for valvular and coronary artery disease was reviewed in 27 patients. Twelve patients had aortic valve disease and 15 had mitral valve disease. Forty-seven coronary artery reconstructions were performed, and average of 1.7 per patient. Twenty-two patients underwent valve replacement and 5 had valvuloplasty. Congestive heart failure was the major symptom in 20 patients, and angina was the major symptom in 7. Eight of the patients with congestive heart failure had no angina, but significant coronary stenoses were demonstrated at routine coronary angiography. Coronary reconstruction was performed before valve repair. Two patients died postoperatively (a hospital mortality of 7.4%), and there were 4 late deaths from 2 to 28 months postoperatively. There were no postoperative myocardial infarctions. Contrary to previous reports, coronary artery reconstruction and valve repair need not be associated with an increased risk. Protection of the myocardium by coronary perfusion through reconstructed coronary arteries enables valve repair to be done without greater risk than valve repair alone. All patients considered for valve repair should have coronary angiography.

An intracavitary location of a coronary artery is rare in our surgical experience with myocardial vascularization. This variant has occurred in the right coronary artery (0.09%) and in the left anterior descending coronary artery (0.2%). The location of the lesion and the pathological condition, length, and size of the coronary artery may dictate exposure of an intracavitary coronary artery for proper revascularization. More commonly, surgeons are unaware of the intracavitary position and during intramyocardial dissection of an artery will open a cardiac chamber where the vessel traverses the cavity. Problems that arise are introduction of air, difficulty in exposure due to blood and depth of position, and obstruction of the coronary artery during closure of the myotomy. We report here on 13 patients who required revascularization of intracavitary vessels (four right coronary arteries and six left anterior descending coronary arteries). The location and length of the intracavitary portion of the artery determined the surgical management. The methods used to close the cavity varied. The techniques employed were simple closure; moving the artery into an aerial position with cavitary closure behind it; anastomosis in the intracavitary position with closure of the myotomy around the graft; or selection of an alternate distal site for anastomosis. All patients treated for intracavitary arteries were successfully revascularized without major complications.

This paper describes our experience in performing saphenous vein bypass grafts to the circumflex coronary artery system with a left thoracotomy in 9 patients. Illustrative case reports demonstrate the spectrum of patients for whom this approach has been useful. The advantage of this technique is that it allows the surgeon to avoid the adhesions that make a redo sternotomy time-consuming and potentially dangerous when previously patent saphenous vein or internal mammary grafts are present. It is particularly useful for patients requiring grafting to the circumflex coronary artery system, especially if the patient is in relatively unstable condition and would benefit from rapid institution of cardiopulmonary bypass. The technique generally employs cannulation of the descending thoracic aorta for arterial inflow and of the main pulmonary artery for venous return. Usually the proximal end of the graft is easily placed to the left subclavian artery. Coronary anastomosis is performed on the cold (15 degrees C), fibrillating heart, and aortic cross-clamping and cardioplegic arrest have not been necessary. Venting is possible through the left atrial appendage should any rise in filling pressures occur. Saphenous vein or internal mammary artery may be used. All patients undergoing this technique have had expeditious discharge from the hospital and excellent relief of symptoms. The technique is an alternative to median sternotomy for properly selected patients.

From 1970 to 1985, 246 consecutive patients with left ventricular (LV) aneurysm underwent repair and concomitant myocardial revascularization at Ochsner Foundation Hospital. The overall incidence of perioperative death was 7.3%. Although the deaths were mainly cardiac related (10/18) with congestive heart failure (CHF) as the leading cause (6/10), 8 deaths were of noncardiac origin. Perioperative mortality increased significantly in patients with mitral regurgitation (MR) (22%; p = 0.0008); perioperative mortality for patients without MR was 4.8%. The overall 5-year survival was 69%. Late deaths were caused most commonly by myocardial infarction (20/32) with only 7 due to CHF. Predictors of long-term survival were related to LV function preoperatively: absence of CHF (p = 0.001); LV end-diastolic pressure less than or equal to 20 mm Hg (p = 0.03); and ejection fraction greater than or equal to 35% (p = 0.02). Factors that did not significantly affect long-term survival were type of aneurysm repair (resection or plication), morphology of left anterior descending coronary artery (occlusion or stenosis), and size of the aneurysm.