Yuichiro Kaminishi

Effects of nafamostat mesilate and minimal-dose aprotinin on blood-foreign surface interactions in cardiopulmonary bypass

BACKGROUND The pharmacological inhibition of blood-foreign surface interactions is an attractive strategy for reducing the morbidity associated with cardiopulmonary bypass. We compared the inhibitory effects of nafamostat mesilate (a broad-spectrum synthetic protease inhibitor) and minimal-dose aprotinin on blood-surface interactions in clinical cardiopulmonary bypass. METHODS Eighteen patients undergoing coronary surgery were divided into three groups: (1) the control group (heparin, 4 mg/kg; n = 6), (2) the nafamostat mesilate group (heparin plus nafamostat, 0.2 mg/kg bolus followed by 2.0 mg/kg/h during cardiopulmonary bypass; n = 6), and (3) the aprotinin group (heparin plus aprotinin, 2.0 x 10(4) KIU/kg; n = 6). Platelet count, platelet aggregation, beta-thromboglobulin, prothrombin fragment F1.2, thrombin-antithrombin complex, plasminogen activator inhibitor-1, alpha2-plasmin inhibitor-plasmin complex, D-dimer, neutrophil elastase, and interleukin-6 were measured before, during, and after bypass. Bleeding times and blood loss were recorded. RESULTS There were no significant differences between groups in platelet count, beta-thromboglobulin, plasminogen activator inhibitor-1, interleukin-6, bleeding times, or blood loss. Platelet aggregation was better preserved at 12 hours after surgery in the nafamostat and aprotinin groups than in the control group. Prothrombin fragment F1.2, thrombin-antithrombin complex and neutrophil elastase levels were significantly reduced by aprotinin, but not by nafamostat as compared with the control group. The alpha2-plasmin inhibitor-plasmin complex and D-dimer were significantly lower with either of the drugs. Aprotinin showed better control of D-dimer than did nafamostat. CONCLUSIONS Nafamostat mesilate fails to reduce thrombin formation and neutrophil elastase release, whereas minimal-dose aprotinin inhibits both. Neither nafamostat nor aprotinin inhibits platelet activation. Nafamostat reduces fibrinolysis during cardiopulmonary bypass, although its effect is not as potent as aprotinin.

Isolated Traumatic Vertebral Pseudoaneurysm: Report of a Case

Abstract.We report a case of isolated traumatic pseudoaneurysm of the vertebral artery in a 20-year-old man who suffered blunt injury to the left foreneck and arm in a traffic accident. A chest computed tomography (CT) scan on admission showed an upper mediastinal hematoma, but the patients vital signs were stable. A CT scan of the head and neck showed a cerebral mass, and an elective cerebral four-vessel angiography was performed, whitch revealed a pseudoaneurysm in the proximal portion of the left vertebral artery. At surgery, about 2 cm of the left vertebral artery was found to be lacerated, and suture ligation was done on each side of the laceration. Postoperative intravenous digital subtraction angiography showed an intact right vertebral artery with no residual pseudoaneurysm. There were no neurological complications and the patient was discharged on the 16th postoperative day.

Clinical experience with the Bicarbon heart valve prosthesis.

BacgroundWe have previously reported mid-term results of a study, which ended in January 2000, on the Bicarbon valve. The study concluded that the valve showed excellent clinical results, associated with a low incidence of valve-related complications. In the present study, the same patients were prospectively followed for an additional 5 years.MethodsForty-four patients had aortic valve replacement (AVR), 48 had mitral valve replacement (MVR), and 13 had both aortic and mitral valve replacement (DVR). The mean age of the 105 patients was 61.2 ± 11.3 years. The mean follow-up was 6.1 ± 1.9 years with a cumulative follow-up of 616 patient-years.ResultsThere were 5 early deaths (4.7%: 4 in the AVR group and 1 in the MVR group) and 21 late deaths (3.4%/patient-year: 5 valve related deaths and 16 valve unrelated deaths). Survival at 8 years was 75.2 ± 7.0% in the AVR group, 76.6 ± 6.2% in the MVR group, and 55.4 ± 16.1% in the DVR group. The linearized incidence of thrombo-embolic complications, hemorrhagic complications, and paravalvular leaks in all patients was 0.65 ± 1.48%, 0.81 ± 1.69%, and 0.16 ± 0.54%/patient-year respectively. No other complications were observed.ConclusionThe Bicarbon prosthetic heart valve has shown excellent long-term clinical results, associated with a low incidence of valve-related complications.

Strategies for preventing stroke after coronary artery bypass grafting

UNLABELLED To evaluate the usefulness of our strategy for preventing stroke after CABG, 343 consecutive patients were investigated retrospectively. Patient ages ranged from 32 to 31 years (mean; 63 +/- 9 years). There were 254 males and 59 females. Number of grafts per patient was 1 to 5 (mean 2.4 +/- 0.9 grafts). In 193 patients, internal carotid arteries (ICAs) were preoperatively evaluated by duplex scanning or cerebral angiogram. The degree of atherosclerosis in the ascending aorta was preoperatively examined by plain computed tomography in 181 patients, during surgery by ultrasonography in 75 patients and palpation in all patients. RESULTS 1. On preoperative examination, there were 26 patients (15.1%) with ICA stenosis greater than 50% and 15 patients (7.8%) with stenosis greater than 75%. Six patients had bilateral ICA stenosis or occlusion greater than 75%. In 26 patients with ICA stenosis greater than 50%, history of stroke was significantly more prevalent than that in 167 patients without ICA stenosis (12 patients: 46.2% vs 22 patients: 13.1%, p < 0.001). In patients with ICA stenosis greater than 75%, 6 patients were symptomatic and 8 were asymptomatic. For these patients, concomitant carotid endarterectomy and CABG were performed in 5, two stage procedures in 7 reconstruction of cerebral perfusion followed by CABG;4, followed by CEA: 3), and CABG alone in 3. There was no stroke in any of these patients. 2. Atherosclerosis of the ascending aorta was found in 69 of 343 patients (20.1%). In these patients, single clamp technique was applied in 50 patients, aortic no touch technique in 12 and CABG without cardiopulmonary bypass in one. The arterial cannulation site was changed to femoral artery in 15 and to axillary artery in 6 patients. Statistical analysis indicated that age (older than 60 years) and history of stroke were significant risk factors for atherosclerotic ascending aorta. 3. There were 3 patients (0.9%) with perioperative stroke caused by embolism from the ascending aorta in one and hypoperfusion of the brain during cardiopulmonary bypass in two. CONCLUSION Proper treatment of atherosclerotic ascending aorta and carotid occlusion may reduce the incidence of stroke in CABG patients.

Modified Bentall operation in a patient with hemophilia A.

We detail a successful modified Bentall operation in a patient with hemophilia A. A 53-year-old man with mild hemophilia A and a history of few bleeding episodes was diagnosed with annuloaortic ectasia. Surgical repair was planned. Simple bolus infusions of factor VIII concentrate were given before and after cardiopulmonary bypass to achieve 100% blood levels and postoperatively every 12 hours for 7 days to maintain 50% levels. The patient received no transfusion other than 10 units of platelet concentrate. We used routine operative and cardiopulmonary bypass techniques. The patient recovered well postoperatively with no excessive bleeding despite warfarin therapy.

Aorto-Right Atrium Fistula Caused by Detachment After Bentall's Operation: Report of a Case

A 70-year-old woman was admitted to our hospital for treatment of right heart failure 16 years after undergoing Bentalls operation with a Cabrol shunt procedure. Various investigations showed detachment of the coronary artery and graft. We surmised that the heart failure was caused by a massive left to right shunt between a pseudoaneurysm of the wrapping aortic wall and the right atrium. Intraoperatively, we found a small fistula between the wrapping aortic wall and the right atrium, with complete closure of Cabrol shunt. We performed regrafting of the ascending aorta and reconstruction of the coronary ostium under cardiopulmonary bypass. The patient had an uneventful postoperative course. Detachment of the coronary ostium is a common long-term complication of Bentalls operation, but a Cabrol shunt between the wrapping aortic wall and the right atrium rarely causes congestive heart failure. A fistula between a pseudoaneurysm and the right atrium is even more unusual.

Non-perforating pericardial rupture causing cardiac tamponade.

A 51-year-old auto truck driver was transferred to our hospital after crashing. He had a severe pain on the left anterior chest wall with high central venous pressure of 30 cm H(2)O. Surveillance of the chest revealed cardiac tamponade and the right seventh rib fracture with left pleural effusion. Pericardiotomy through median sternotomy led to extrusive bloody pericardial effusion. Non-perforating pericardial laceration at the site of the adjoining muscular structure of the diaphragm was repaired with direct suture closure. His postoperative course was uneventful.

A worn Björk–Shiley prosthetic valve without valve dysfunction observed during ascending aortic replacement

The implanted first‐generation Björk–Shiley valve in our patient was functioning well before aortic surgery, but we replaced the valve because we confirmed disc erosion 39 years after implantation during the surgery. We judged that the implanted valve was no longer capable of maintaining the patients life.

Successful surgical treatment of chronic traumatic thoracic aneurysm in two patients

We successfully treated two patients with chronic traumatic aneurysm of the thoracic aorta. The first, a 40-year-old man involved in an automobile accident 24 years earlier, was treated by thoracic aorta graft replacement via left thoracotomy under femoro-femoral partial bypass. The second, a 57-year-old man with a 3-month history of hoarseness who had suffered blunt chest trauma 17 years earlier, was treated similarly. Both had a calcified pseudoaneurysm at the isthmus of the descending aorta, but neither had atherosclerosis other than at the aneurysm site. They have done well after surgery. We believe chronic traumatic thoracic aneurysm at the aortic isthmus should be treated surgically soon after diagnosis because elective surgery presents low risk of morbidity and mortality.

Starr-Edwards valves at the aortic and mitral positions implanted for 39 years.

Cloth-covered Starr-Edwards caged ball valves implanted in the aortic and mitral valve positions for 39 years were extracted. Both showed valve dysfunction resulting from pannus overgrowth. The metal cages of the Starr-Edwards valves were covered with worn cloth. This case indicates the extended durability of Starr-Edwards valves and the importance of the design and materials of prosthetic heart valves to avoid pannus overgrowth and prosthetic valve abrasion.