Cardioprotective properties of sevoflurane in patients undergoing aortic valve replacement with cardiopulmonary bypass

In coronary surgery patients the use of a volatile anesthetic regimen with sevoflurane was associated with a better recovery of myocardial function and less postoperative release of troponin I. In the present study we investigated whether these cardioprotective properties were also apparent in the cardiac surgical setting of aortic valve replacement (AVR) surgery for the correction of aortic stenosis. Thirty AVR surgery patients were randomly assigned to receive either target-controlled infusion of propofol or inhaled anesthesia with sevoflurane. Cardiac function was assessed perioperatively using a pulmonary artery catheter. Perioperatively, a high-fidelity pressure catheter was positioned in the left ventricle. Postoperative concentrations of cardiac troponin I were followed for 48 h. After cardiopulmonary bypass (CPB), stroke volume and dP/dt(max) were significantly higher in the patients with sevoflurane. Post-CPB, the effects of an increase in cardiac load on dP/dt(max) were similar to pre-CPB in the sevoflurane group (1.0 % +/- 5.4% post-CPB versus 1.3% +/- 8.6% pre-CPB) but more depressed in the propofol group (-8.2% +/- 4.4% post-CPB versus 0.1% +/- 4.9% pre-CPB). The rate of relaxation was significantly slower post-CPB in the propofol group. Postoperative levels of troponin I were significantly lower in the sevoflurane group. Our data indicate that the use of a volatile anesthetic regimen in AVR surgery was associated with better preservation of myocardial function and a reduced postoperative release of troponin I.     

Tracheal reconstruction with mitral valve replacement under cardiopulmonary bypass: A case report

A-54-year-female patient suffering from rheumatic heart disease mitral stenosis, NYHA class IV with pulmonary edema ventilated for one week. She developed postintubation tracheal stenosis. Mitral valve replacement with tracheal resection and reconstruction under Cardio Pulmonary Bypass (CPB) was planned. Mitral valve replacement was done under CPB which was continued to resect and reconstruct trachea. Endotracheal tube was reinserted beyond anastomosis and ventilation started. Postoperatively neck flexon stitch kept for one week and repeat fibreoptic bronchoscopy was done to clear endotracheal secretions. postoperative period was uneventful except left vocal cord palsy.     

Life threatening cardiopulmonary failure in an infant following protamine reversal of heparin after cardiopulmonary bypass

Life threatening cardiopulmonary failure following protamine reversal of heparin after cardiopulmonary bypass (CPB) was reported to occur in adults but rarely in children. Atrial septal defect closure was performed in a 6-week-old infant erroneously suspected to suffer from right atrial thrombosis in addition. Protamine administration after CPB led to critical pulmonary hypertension and severe haemorrhagic pulmonary oedema resulting in severe hypoxia. Inhaled nitric oxide, together with high frequency oscillation ventilation supplemented by intravenous prostacycline, enabled complete recovery of cardiopulmonary and neurological function. Life threatening cardiovascular compromise after intravenous protamine can occur even in young infants which then require challenging paediatric critical care.     

Comparison of two protocols for heparin neutralization by protamine after cardiopulmonary bypass

Twenty patients undergoing cardiac operations were randomly assigned to two protocols for heparin neutralization by protamine after cardiopulmonary bypass. In all patients protamine chloride was given at a ratio of 1 unit of protamine to 1 unit of injected heparin. In Group I (10 patients) all protamine was infused within 10 minutes after termination of cardiopulmonary bypass. Group II (10 patients) received 75% of the calculated protamine dose within 10 minutes after termination of bypass and the remainder after transfusion of all blood in the heart-lung machine. Plasma heparin levels were significantly lower in Group II 5 minutes after transfusion of all blood in the heart-lung machine and were 0.13 units/ml (standard deviation 0.04) in Group I and 0.06 units/ml (standard deviation 0.05) in Group II (p less than 0.001) 60 minutes after bypass. Activated partial thromboplastin time mirrored the changes in plasma heparin, whereas activated clotting time (Hemochron) was too insensitive to detect these low plasma heparin levels. We conclude that the two-dose protocol resulted in more complete heparin neutralization than the one-dose protocol.     

A case of minimal invasive aortic valve replacement for quadricuspid aortic valve with aortic regurgitation]

Congenital quadricuspid aortic valve is rare, which may be a cause of sever aortic regurgitation. We report a case of a 55-year-old man who had severe aortic regurgitation with congenital quadricuspid aortic valve. Preoperative aortography showed severe aortic regurgitation. Preoperative trans-esophageal echocardiography revealed abnormal quadricuspid aortic valve. We performed minimal invasive aortic valve replacement with SJM # 21 mm HP prosthetic valve through the limited upper sternotomy. Skin incision was 9 cm. Aortic cross-clamping time was 92 min, cardiopulmonary bypass time was 108 min. At the operation, a quadricuspid valve with three equal cusps and one small cusp was noted. The postoperative course was excellent and he discharged 8 days after the operation.     

Adverse events after protamine administration following cardiopulmonary bypass in infants and children

We performed this study to determine the incidence of and risk factors for adverse events (AEs) in infants and children after the IV administration of protamine after cardiopulmonary bypass. In a retrospective cohort study, all relevant anesthesia records from a 3-yr period were examined to identify AEs after protamine. The AEs were then grouped into three categories by applying increasingly strict criteria. Among 1249 anesthesia records, there were no documented episodes of isolated or hypotension-associated right-sided cardiac failure or acute pulmonary dysfunction. The incidence of systemic hypotension after protamine was between 1.76% (95% confidence interval [CI], 1.11%-2.65%) and 2.88% (95% CI, 2.03%-3.97%), depending on the strictness of case definition. To identify risk factors, we performed a nested case-control study in which unmatched controls were randomly selected from the parent cohort at a 4:1 ratio to cases. Cases of hypotension after protamine were more likely during operations on girls (odds ratio [OR], 6.47; 95% CI, 1.66-32.8), after larger doses of protamine (OR, 1.88; 95% CI, 1.03-3.63), or after smaller doses of heparin (OR, 0.49; 95% CI, 0.17-0.67). IMPLICATIONS: Systemic hypotension after protamine administration occurred in 1.76%-2.88% of pediatric patients having cardiac surgery. Female sex, larger protamine dose, and smaller heparin dose were each associated with increased risk. The development of protamine alternatives or prophylactic therapies may be useful for reducing the frequency of these events.     

Mortality and adverse events after protamine administration in patients undergoing cardiopulmonary bypass

We designed this study to determine whether adverse hemodynamic events after a protamine administration increase the risk of in-hospital mortality. Using a retrospective cohort study design, medical and anesthesia records of patients undergoing cardiopulmonary bypass (CPB) at the Hospital of the University of Pennsylvania, Philadelphia, between 1990 and 1994 were reviewed. Adverse events after a protamine administration were determined using strict, predefined criteria, and in-hospital mortality was assessed without knowledge of exposure status. Mortality was more frequent among the 53 patients with adverse events (13.2%) than the 223 patients without events (2.7%; crude odds ratio 5.50; 95% confidence interval, 1.49-20.6). After adjusting for confounders, the odds ratio was 6.98 (95% confidence interval, 1.36-35.9; P = 0.017). Those suffering severe events had the highest mortality (23.5% compared with 8.3% among those with less severe events versus 2.7% among those without any event, P = 0.001 for trend). In addition, the odds ratio was largest when using the strictest definition for protamine-related events. In conclusion, patients undergoing CPB who experience adverse events after a protamine administration have an increased risk of in-hospital mortality. Further studies to confirm these findings and development and testing of protamine alternatives or prophylactic therapies are required to determine if mortality can be reduced. IMPLICATIONS: A retrospective cohort study demonstrated an association between adverse events after a protamine administration and increased in-hospital mortality.     

Successful aortic valve replacement using dilutional ultrafiltration during cardiopulmonary bypass in a patient with Child-Pugh class C cirrhosis

Open-heart surgery is a relatively high-risk procedure when performed in patients with Child-Pugh class C cirrhosis. Even though they can tolerate cardiac surgery with cardiopulmonary bypass (CPB), most of them suffer major postoperative complications and prolonged hospital stay. The present report describes a case of a patient with Child-Pugh class C cirrhosis who developed severe heart failure secondary to aortic valve stenosis. The patient underwent successful aortic valve replacement with the use of dilutional ultrafiltration during CPB to reduce adverse effects of CPB. He recovered smoothly after the operation without major postoperative complications. Thus, the use of dilutional ultrafiltration (DUF) during CPB appears to produce beneficial effects for improving outcomes in patients with decompensated cirrhosis who require open-heart surgery.     

A case of ascending aortic dissection after aortic valve replacement in congenital bicuspid aortic valve]

Congenital bicuspid aortic valve is a risk factor of aortic dissection, but the case is rare in Japan. Several reports described ascending aortic aneurysm after aortic valve replacement. In these reports, most of aneurysms were false aneurysm, but the cases of ascending aortic dissection were rare. In this case, dissecting aneurysm of the ascending aorta occurred 4 years after aortic valve replacement, which was performed with mechanical prosthesis because of infective endocarditis, and it was repaired successfully by the modified Cabrol's method. This case was congenital bicuspid aortic valve, and had already been complicated with moderate aortic dilatation in the ascending aorta. In patients of congenital bicuspid aortic valve with aortic dilatation, consideration of complete replacement of the ascending aorta with aortic valve replacement is important.     

Surgical treatment of interrupted aortic arch with extraanatomical bypass simultaneous to coronary artery bypass grafting and aortic valve replacement

An interrupted aortic arch accompanied by further surgically reparable cardiac lesions is a rare combination in adult patients. We describe treatment of an interrupted aortic arch, coronary artery bypass grafting (CABG), and aortic valve replacement (AVR) performed simultaneously through median sternotomy in a 64-year-old man. The patient underwent surgery performed using standard cardiopulmonary bypass with cannulation of the ascending aorta and the right atrium, hypothermia (24.6degreesC), and blood cardioplegic arrest. Four aortocoronary vein grafts and pericardial aortic valve replacement were carried out. Finally, the posterior pericardium was opened, and a 16-mm prosthesis was anastomosed to the descending aorta during side clamping using a 4-0 monofilament continuous suture. Optimal placement of the prosthesis was obtained by guiding it to the ascending aorta laterally to the right atrium and passing it between the inferior vena cava and right inferior lung vein. The operation was carried out without complications, and the postoperative course was uneventful. Magnetic resonance imaging showed competent aortic valve prosthesis and highly decreased collateral flow via the internal mammary arteries. Postoperatively both inguinal pulses were present, and the patient was free of angina. In the presence of an interrupted aortic arch, extraanatomical bypass via the posterior pericardium between the ascending and descending aorta can safely be performed at the same time as CABG and AVR through a median sternotomy.     

Pulmonary valve replacement using the right ventricle-pulmonary artery bypass without cardiopulmonary bypass

We underwent pulmonary valve replacement using the right ventricule pulmonary artery bypass without cardiopulmonary bypass. This right heart bypass was consisted of the vascular graft and the polystyrene tube. The vascular graft was anastomosed to the main pulmonary artery and the polystyrene tube was inserted into the free wall of the right ventricle. These were connected with a cannulating magnetic flow probe. After the bypass was established, the pulmonary artery was clamped and divided. The pulmonary valves were excised and the pulmonary valve replacement was undergone with a pulmonary valve homograft. Hemodynamics during the pulmonary valve replacement was stable and the postoperative course was uneventful. One month later, the cardiac catheterization and cineangiography showed that the implanted homograft was effective sufficiently. We concluded that this right heart bypass was useful for the pulmonary valve replacement.