Under scheduled anticoagulation therapy, surgery for abdominal aortic aneurysm was performed in 4 patients who had undergone heart valve surgery and implantation of a mechanical prosthesis. Warfarin and antiplatelet agents were prescribed in all cases preoperatively. Antiplatelet agents were discontinued from seven to 10 days before operation. Warfarin was stopped from two to three days before operation and heparin (200IU/kg/day) was administered by continuous intravenous infusion to produce an activated clotting time of around 150 seconds. Bolus intravenous heparin of 3, 000 IU was added before aortic crossclamp. Oral anticoagulants were resumed from the beginning of oral intake, and heparin was stopped when the prothrombin time reached therapeutic levels (% PT=40%). In three patients perioperative courses were uneventful. Intraperitoneal hemorrhage occurred in one patient who simultaneously underwent cholecystectomy and aneurysmectomy with Y-grafting. He required blood transfusion and interruption of anticoagulation. Brain thromboembolism occurred in this patient 26 days after the operation. We believe that scheduled anticoagulation for the operation of abdominal aortic aneurysm is safe and useful in patients with prior prosthetic heart valve surgery. However, the coexistence of coagulopathy requires more intensive anticoagulation therapy.

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A Pulmonary arterial flow-directed catheter (Oxymetry 93A-741-7.5F), combining the fiberoptic reflectometric system of continuous measurement of mixed venous blood oxygen saturation (SvO₂) was used for hemodynamic measurements including thermodilution cardiac output estimation and hemoglobin value in 21 cases of open heart surgery. Immediately after open heart surgery there was low correlation between Hb (hemoglobin value) and SvO₂ (r=0.513, p<0.05). However there was no correlation between SvO₂ and cardiac function (pulmonary capillary wedge pressure and cardiac index). With almost normal Hb (10-13g/dl) the average cardiac index (CI) in cases of SvO₂ less than 60% was 2.47l/min/m² which was significantly lower than those with SvO₂ more than 60% (p<0.01). With normal CI (2.5-4.0l/min/m²) the average Hb in cases of SvO₂ less than 60% was 7.40g/dl which was significantly lower than those of more than 60% (p<0.01). This study suggested that there is low cardiac function or severe anemia in the state of SvO₂ less than 60%.

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To estimate the microcirculation of major organs in pulsatile and nonpulsatile assisted circulation, a comparative study was made, using a cardiogenic shock model. Acute myocardial infarction was made by ligating the left anterior descending branches. After falling into cardiogenic shock, animals were divided into three groups as follows, group C (n=6) received no assist, group NP (n=6) was assisted by a nonpulsatile pump (BioMedicus), group P (n=6) was supported by a pulsatile pump (Nippon Zeon). Left coronary artery flow, endocardial and epicardial regional blood flow, liver, renal cortex and medulla blood flows were measured in the three groups. Each group was treated for two hours. Left coronary flow, epicardial and endocardial tissue blood flow decreased in cardiogenic shock, but recovered to control level soon after support in both NP and P groups. Liver regional blood flow which was decreased in cardiogenic shock recovered control value after 2 hours assist only in group P. There was a statistically significant (p=0.05) difference between groups N and P. Renal medulla and cortex blood flow decreased in cardiogenic shock. Especially cortex blood flow remarkably decreased, showing reversed re-distribution between medulla and cortex. This distribution did not recover in any group. However, cortex blood flow of group P improved rather than that of group N after 2 hours assist, demonstrating a statistically significant (p<0.05) difference. These results suggest that pulsatile assist was more effective than nonpulsatile assist for microcirculation after cardiogenic shock in preventing deterioration of major organ functions.

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We studied the incidence of associated ischemic heart disease (IHD) among 143 consecutive patients (male 118, female 25, mean age 68.5±6.9 years) operated upon for abdominal aortic aneurysm (AAA), excluding ruptured aneurysms. The screening of IHD was routinely performed by using dipyridamole thallium scintigraphy, and when it was positive, the lesion was further confirmed by selective coronary angiography. More than 50% luminal stenosis of the major coronary arteries was judged positive for IHD. Sixty-two patients (43%) with AAA were simultaneously afflicated with IHD. We also compared the 62 AAA patients with IHD with the remaining 81 AAA patients in this series. The patients with IHD had higher incidences of risk factors such as diabetes mellitus (p=0.0031) and hyperlipidemia (p=0.0029) than those without IHD. Five patients were operated on for AAA after coronary artery bypass grafting (CABG), 11 were operated on for AAA and IHD (CABG) simultaneously, 10 were operated on after PTCA, thirty-two patients underwent elective surgery for AAA and four had emergency procedures due to impending rupture of AAA with continuous infusion of nitroglycerin with or without diltiazem. There was no significant difference in surgical mortality between AAA patients with IHD and those without IHD (3%vs2%), and no cardiac death in this series. When both AAA and IHD are severe enough to warrant surgical treatments at the earliest opportunity, we recommend concomitant operations for AAA and IHD (CABG) since these have been performed quite successfully in our series.

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Primary end-to-side anastomoses between the left upper pulmonary vein and left atrium performed in 21 puppies with continuous 5-0 polydioxanone (PDS) or polypropylene (PRO). Animals were sacrificed at 1, 7 and 28 days after operation. Stenosis occurred in one of 5 animals of the PDS group at 7 days and 28 days respectively, and one of 5 animals of the PRO group at 28 days. There was no significant difference between the two groups in terms of anastomosis patency. Histological examination showed slight tissue reaction and fibrosis surrounding the sutures in both groups. This study suggests that the absorbable monofilament suture material, in particular PDS, is useful for the repair of low pressure circulatory system and will not cause the stenosis of the anastomotic site.

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The surgical replacement of human vessels or valves using allografts (homografts) has been reported as a useful method. Nevertheless, little is known about preservation effects and immunological consequences using low temperature preservation and cryopreservation. In this study, we examined the histological changes and immunological changes of cryopreserved aorta in a rat model, and compared the results with those of low temperature preserved aorta. Ascending aorta was harvested from Wister-King rats and preserved in TC199 solution at 4°C (low temperature preservation group) and cryopreserved (cryopreservation group) for 1, 2, and 3 weeks. The preserved aorta was then transplanted to the abdominal aorta of the recipient rat. The graft patency and histology, including immunohistochemical stain (IgG, IgM, C3), were assessed at 3 weeks after transplantation. In the cryopreservation group prominent intimal thickness was observed. However, cell infiltration from adventitia was observed in the low temperature preservation group. Immunohistochemical stains indicated the deposit of immunoglobulin was seen after transplantation in both groups. The result of this study suggested that successful preservation of aorta was possible at one week with low temperature preservation and 3 weeks with cryopreservation in the rat model.

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A 6-year-old girl who had undergone repair of an endocardial cushion defect 4.5 years previously, developed discrete subaortic stenosis requiring surgical intervention. On two-dimensional echocardiography a membrane was visualized below the aortic valve. A pressure gradient of 97mmHg was recorded across the left ventricular outflow tract by cardiac catheterization. Operative findings showed a fibrous ring tissue just below the aortic valve, which was peeled away by sharp dissection. Postoperative cardiac catheterization revealed a 25mmHg pressure gradient across the left ventricular outflow tract. Two years later, she continues to do well and the pressure gradient remains unchanged on Doppler echocardiography.

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We present a case of solitary arteriosclerotic aneurysm of the profunda femoris artery (PFA), which is very rare among peripheral aneurysms and a reviewed the 19 cases reported in the Japanese literature. A 78-year-old man had a chief complaint of a painful pulsatile mass in the left thigh. Enhanced CT showed the ruptured solitary aneurysm of the PFA. The aneurysm was 6.8cm in diameter. It was removed after ligation of the the PFA. In the Japanese literature, the mean age of patients with solitary arteriosclerotic aneurysm of the PFA was 73 (64-84), all patients were males, the rate of rupture of PFA aneurysm was 47%, and the mean diameter was 8.9cm. In our case, we simply ligated the aneurysm because the patient did not have any evidence of peripheral artery occlusive disease and the distal artery of the aneurysm was very small. However, there is a need to reconstruct the PFA whenever possible because the surgical importance of PFA in occlusive arterial disease has been recognized.

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Tuberculous valvular endocarditis is rare and diagnosis before death is seldom achieved. A case of severe aortic regurgitation due to tuberculous endocarditis in a 56-year-old man is presented. Replacement of the aortic valve in emergency and administration of anti-tuberculuos medication permitted an uneventful recovery. This is a rare case report of successful surgical treatment of tuberculous valvular disorder.

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A 54-year-old male with sudden back pain was diagnosed as having acute aortic dissection of Stanford type A. He underwent an aortic arch replacement under the deep hypothermic circulatory arrest and retrograde cerebral perfusion. During retrograde cerebral perfusion, the central venous pressure was maintained at 20mmHg, the perfusion flow rate was 400ml/min and the lowest rectal temperature was 19°C. The duration of retrograde cerebral perfusion was 135 min, but the patient recovered successfully without any evidence of neurological complications. This report suggests that retrograde cerebral perfusion associated with deep hypothermic circulatory arrest has the possibility to prolong the safety time limit of antegrade cerebral circulatory arrest up to 135min.

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We report two cases, a 58-year-old male and a 60-year-old female with acute aortic occlusion probably ascribable to intracardiac thrombosis associated with atrial fibrillation. Thrombectomy was performed at about 5.5 hours and 4 hours respectively, after the onset of occlusion, and revascularization was successful. To prevent MNMS after revascularization, about 2, 000ml of blood was taken from the femoral vein of the male patient, and 1, 000ml of blood from the female patient, and this blood was returned in the form of abluted erythrocytes in transfusion through a cell saver to the patients. We suspected slight myoglobinuria after the operations, but they did not develop MNMS because a urine volume of about 3, 000ml was maintained by administration of infusion solution and diuretics and by replenishment of electrolytes and correction of acidosis. It was concluded that the technique involving the removal of a large volume of blood from distal veins and its transfusion through a cell saver was effective in preventing MNMS.

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A 59-year-old male suffered dyspnea and ischemia of the lower limbs due to myocardial infarction (occlusion of the right coronary artery and 99% stenosis with delay in the left anterior descending artery) and juxtarenal aortic occlusion, respectively. Juxtarenal aorto-femoral bypass operation using a Y-shaped prosthesis and coronary arterial bypass grafting using the left internal thoracic artery (LITA) and right gastroepiploic artery (RGEA) were performed simultaneously. As the left internal thoracic artery was the route of collateral blood flow to the left lower limb, aorto-femoral bypass was initially made prior to aorto-coronary bypass operation. Because of complete obstruction of the abdominal aorta and juxtarenal lumbar arteries, neither hemodynamic changes nor bleeding occurred during the reconstruction of the abdominal aortic occlusion in spite of severe coronary disease. This procedure was useful for protection of limb ischemia and shortage of extracorporeal circulation time, in addition to producing a route for insertion of an intraaortic balloon pumping catheter.

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The results of complete graft replacement for thoracoabdominal aortic aneurysm remains unsatisfactory. The operative strategies, including the method of reconstruction of visceral vessels and the protection of abdominal organs and spinal cord, are controversial. Two male patients (53 and 59 years of age) had thoracoabdominal aortic aneurysms including the celiac artery and small abdominal aortic aneurysm in the renal arterial part. They underwent replacement of a large aneurysm using a Dacron prosthesis with reconstruction of the celiac artery. The remaining small aneurysm was wrapped by a bandage of Teflon tape 3mm in width. This wrapping technique was easy to perform and could be sufficiently adapted to the aneurysm preserving visceral arterial branches. The postoperative courses were uneventful. Their postoperative enhanced CTs (41 months and 26 months after surgery, respectively) revealed no enlargement of the wrapped aortic aneurysm and no stenosis of the visceral branches. This result suggests that our wrapping method is useful to reinforce the wall of small aortic aneurysms.

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A 67-year-old man had been diagnosed as having aplastic anemia three years ago. He had taken anabolic steroids continuously. He suddenly complained of the ischemic signs of the lower extremities. Aortography showed the total occlusion of the abdominal aorta with encroachment upon the left renal artery. The right renal artery and superior mesenteric artery were intact. Laboratory data showed acute renal failure. We selected an axillo-femoral bypass because of aplastic anemia and acute renal failure. Throughout the intraoperative and post-operative periods the patient showed a bleeding tendency, then disseminated intravascular coagulation (DIC) has occurred. He required much blood transfusion, anti-coagulant drugs and hemodialysis post-operatively and finally recovered from acute renal failure and DIC.

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A 59-year-old woman was referred to our hospital with a complaint of a pulsatile mass in the right inguinal region four months after total hip replacement. Right femoral arterial injury owing to continuous contact with a fold of excess cement used in the fixation of the hip prosthesis was suspected to be the cause of the false aneurysm. Moreover, two months after the total hip replacement, the right lower leg was amputated at the below-knee level for acute ischemia due to arterial thromboembolism probably originating from the false aneurysm. False aneurysm due to direct vascular injury deserves consideration as a possible complication of total hip replacement.

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