This study was designed to assess the role of macrophages in saphenous vein graft disease after coronary artery bypass grafting (CABG). Three newly harvested saphenous vein grafts (SVGs) and 6 SVGs removed from patients 8 to 15 years after CABG (3 were occluded soon after the operation and 3 became diseased after a long period) were immunostained for macrophages and investigated microscopically. No macrophages were detected in the newly harvested SVGs. In the grafts with early occlusion, macrophages were detected only in the superficial layer of the intima. In the grafts that became diseased after a long period, macrophage accumulation was detected at the site of atherosclerotic lesions. In the pathogenesis of arterial atherosclerotic lesions, vascular endothelial cell damage and subsequent subendothelial migration of monocytes/macrophages in the early phase are thought to be very important. This study revealed that macrophage migration into the intima of SVGs occurs soon after surgery and suggested it could be the basis of saphenous vein graft disease occurring long after CABG.

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Recent studies have reported parasympathetic ganglia supplying the regions around the sinoatrial node (SAN) are situated in the pulmonary vein fat pad (PVFP). Otherwise, in coronary artery bypass grafting (CABG) without cardiopulmonary bypass, cardiac surgeons expect effective support technique on heart rate. The purpose of this study was to determine the feasibility of inducing sinus bradycardia by stimulating these parasympathetic nerve fibers to the SAN in humans. Nine patients were anesthetized and median sternotomy was performed. Bipolar electrodes were sewn onto PVFP to stimulate parasympathetic nerve fibers to the SAN. PVFP was electrically stimulated with a 4-9 V pulse of 0.1msec and a frequency of 5, 10, 20, or 50Hz. Sinus bradycardia was induced by selective stimulation of the parasympathetic nerve fibers to the sinoatrial node. The response was frequency-dependent up to 20Hz. Heart rate was significantly reduced from 90.1±12.4 to 71.4±15.7 (beats/min) at 20Hz. This technique could be applied for reducing heart beats in CABG without cardiopulmonary bypass. However, there are problems in maintaining of the effect.

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In the last decade, 78 patients received operations for abdominal aortic aneurysms with a transperitoneal approach (TP) while in 82 patients we used an extraperitoneal approach (EP). Forty-two patients in the TP group and 40 in the EP group who required no concurrent repair of the inferior mesenteric artery, renal artery or lower extremity arteries were compared. There was no difference between the two groups in mean operative time, mean amount of intraoperative bleeding or mean amount of required homologous blood transfusion. The mean interval after surgery to beginning peroral alimentation and the mean duration of postoperative fluid therapy were significantly shorter in the EP group than in the TP group. An extraperitoneal approach for abdominal aortic reconstruction is preferable for an early postoperative recovery.

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We herein review the early results of minimally invasive coronary artery bypass (MIDCAB). From April 1994 to November 1998, 23 patients underwent MIDCAB, and 12 patients underwent coronary artery bypass grafting with cardiopulmonary bypass (CABG). We compared and analyzed the findings of these two groups. Regarding preoperative factors, the MIDCAB group included elderly patients, while the CABG group consisted of younger patients. However, the frequency of hemodialysis, respiratory disorders and cerebral vascular accidents did not differ significantly between the 2 groups. Regarding perioperative factors, the MIDCAB group needed a shorter operation time, and also had a lower bleeding volume, and a low incidence of blood transfusion. Regarding the postoperative course, the MIDCAB group needed a shorter artificial respiration time, and a shorter postoperative hospital stay, and no mortality was observed. The graft patency of the MIDCAB group was lower (88%) than the CABG group (100%). However, the graft patency of the MIDCAB group reached 94% after we used a stabilizer in the operation. In conclusion, the operation results of the MIDCAB group were comparatively better than those of the CABG group. Thanks to recent technological advances, the results of MIDCAB continue to improve. Though MIDCAB remains an invaluable operative modality for the treatment of one-vessel disease, surgeons must be careful to select appropriate candidates for this operative method.

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Lecithinized superoxide dismutase (L-SOD) has a higher affinity for cell membranes than recombinant human superoxide dismutase has. The purpose of this study, is to evaluate the protective effects of L-SOD against ischemia/reperfusion injury in blood-perfused isolated rat heart subjected to 30-min global normothermic ischemia. Fifteen isolated hearts were divided into three groups: group I (n=5), the untreated control group, group II (n=5) received 3, 000 units of L-SOD administered into the perfusion circuit at the beginning of reperfusion, and group III (n=5) received 3, 000 units of L-SOD administered into the perfusion circuit 10min after reperfusion. Left ventricular developed pressure, maximum positive and negative dp/dt, coronary vascular resistance and myocardial water content were assessed in each group. The percent recovery of left ventricular developed pressure in group II was significantly higher than that in group I and group III (77.4±11.1% in group II, 38.2±4.4% in group I, 40.2±4.1% in group III, p<0.01). The percent recovery of maximum positive dp/dt in group II was significantly higher than that in group I and group III (70.0±11.2% in group II, 41.8±7.8% in group I, 38.0±5.7% in group III, p<0.01). The percent recovery of maximum negative dp/dt in group II was also significantly higher than that in group I and group III (74.9±11.0% in group II, 41.3±8.0% in group I, 46.3±5.9% in group III, p<0.01).There was no significant difference of coronary vascular resistance or myocardial water content among the three groups. These results suggest that L-SOD administered at the time of reperfusion has protective effects against ischemia/reperfusion injury in the isolated rat heart.

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This study was designed to assess the correlation of brain natriuretic peptide (BNP) levels with cardiac function and to determine the usefulness of BNP as a prognostic marker in patients undergoing cardiac valvular surgery. We measured plasma levels of BNP in 53 patients who had undergone aortic valve replacement (AVR) or aortic and mitral valve replacement (DVR) more than 1 year earlier. These cases were divided into the aortic stenosis (AS) group and an aortic regurgitation (AR) group. Fifty-two patients were in NYHA class I, and 43 (82.7%) of them had plasma levels of BNP above the normal range. There were significant correlations between the plasma levels of BNP and ejection fraction (EF) in both the AS and AR groups (r=-0.460, p<0.05; r=-0.529, p<0.01). In the AR group, BNP showed significant correlations with LVMI and LVDd (r=-0.469, p<0.05; r=0.680, p<0.0001), whereas, in the AS group, BNP showed no significant correlation with these factors. The most remarkable finding was the development of heart failure in 3 patients whose plasma levels of BNP were over 80pg/ml, despite remaining in NYHA I during follow-up. We concluded that plasma levels of BNP in a late phase after AVR or DVR can be an excellent biochemical marker for predicting of heart failure and overall prognosis.

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The purpose of this study was to consider the cause of the prolonged inflammatory reaction that sometimes appears after endovascular stent-graft repair for dissecting aortic aneurysm. Endovascular stent-grafting was performed in 12 patients (11 men and 1 woman, mean age 60±9.8). Endovascular stent-grafting was indicated to close the entry of type B dissections in 10 patients and to exclude ulcer-like projections (ULP) in 2 patients. On the 7th postoperative day (POD), aortography showed no endoleak in 7 type B cases (A-group), remaining endoleak in 3 type B cases (B-group), and complete exclusion in 2 ULP cases (C-group). The value of FDP-E in the A-group was high on the first POD and then decreased gradually. FDP-E also increased up to the 7th POD in the B-group, and increased very slightly after the operation in the C-group. The values of WBC and CRP increased up to the 3rd POD in all groups, but in the A-group it was still high on the 7th POD. On contrast-enhanced CT performed after the procedure and on the 7th POD, edema (over 10mm in thickness) around the descending thoracic aorta was demonstrated in 5 out of 7 cases in the A-group, but in none of the cases in the B- and C-groups. A segmental atelectasis in the left lung was detected in 6 out of 7 cases in the A-group, but in none of the cases in the Band C-groups. In the A-group, endovascular stent-grafting influenced thrombus formation, and the thickened edema around the descending thoracic aorta and the atelectasis produced in the left lung were prominent more than in the other groups. These results suggest that the Inflammation around aortic wall induced by thrombosis in the false lumen, might contribute to the development of the edema around the descending thoracic aorta and the atelectasis in the left lung. We conclude that the inflammatory reaction might have prolonged the postoperative course in the A-group patients.

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A 71-year-old man was referred to the University Hospital because of left lumbago and a pulsating mass in his umbilical region. An inflammatory abdominal aortic aneurysm 5cm in diameter and left hydronephrosis were identified by enhanced computed tomography (CT). One month after admission, rapid expansion of the aneurysm with sealed rupture were detected by follow-up enhanced CT. The patient immediately underwent an emergency operation. We confirmed fissure on the posterior aneurysmal wall with a localized hematoma. We replaced the aneurysm with a straight prosthetic graft and the postoperative course was uneventful.

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A 68-year-old man underwent percutaneous transluminal coronary angioplasty (PTCA) to left anterior descending artery (LAD) seg 7 after acute anteroseptal myocardial infarction 8 years previously. He was admitted because of syncope attack due to sustained ventricular tachycardia and subsequent fibrillation. He was treated medically in the ICU after cardiopulmonary resuscitation. Medical treatment with amiodarone and lidocaine was not successful and he was transferred to our hospital for surgical treatment of malignant ventricular tachycardia (VT) associated with left ventricular aneurysm and acute cholecystitis that occurred during admission. Left ventriculogram showed left ventricular aneurysm (ejection fraction: 35%) without any significant coronary lesions. The patient successfully underwent a Dor operation (left ventriculoplasty), double encircling endocardial cryoablation without endocardial resection, and preoperative and intraoperative endocardial mapping. Cholecystectomy was simultaneously performed after complete closure of the median chest incision. The recurrence of VT was never recognized clinically or electrophysiologically. The extended encircling endocardial cryoablation without endocardial resection and preoperative and intraoperative electrophysiological study, was a simple and effective method for ventricular tachycardia.

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A 67-year-old man was considered a candidtate for CABG because coronary angiogram showed obstruction segment 6 and stenoses of segments 9 and 12. He underwent emergency CABG due to acute myocardial infarction (AMI) with cardiogenic shock caused by hemorrhage from a gastric ulcer. Because of hypoxia due to pulmonary edema and acute renal failure an intraaortic baloon was inserted. He had a history of cerebrovascular stroke. Although coronary angiogram revealed multiple vessel disease, we performed off-pump coronary artery bypass (saphenous vein graft-left anterior descending artery) for salvage, because cardiopulmonary bypass was considered very risky and further systemic heparinization might be fatal. He has returned to his job, and is now free from angina. As AMI with cardiogenic shock is often caused by a lesion in the LAD, CABG without cardiopulmonary bypass may be an effective technique in certain selected patients.

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A 50-year-old man had undergone an initial original Bentall operation 19 years previously and replacement of the descending thoracic aorta 3 years previously. Computed tomography and an angiogram revealed a distal arch aneurysm and an ascending aortic aneurysm, neither of which had been detected 3 years previously. Detached anastomosis of the distal site and both coronary ostia were confirmed in the operation. Redo aortic root replacement and total arch replacement were performed successfully. His postoperative course was excellent.

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A 65-year-old woman underwent abdominal aortic replacement using a woven Dacron tube graft for abdominal aortic aneurysm on April 2nd, 1996. She had pyrexia on the 6th postoperative day and abdominal enhanced CT scan showed periprosthetic bubble formations. She underwent relaparotomy 14 days after the initial procedure due to large retroperitoneal abcess bacterial culture of which revealed methicillin resistant staphylococcus aureus. She underwent debridement and local irrigation by an electrolyzed strong acid solution. Her pyrexia diminished immediately after relaparotomy and bacterial culture of the drain of the left retroperitoneal space became negative 82 days later. She was discharged and has had no active inflammatory signs for 3 years. She is doing well at present.

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Mitral regurgitation caused by papillary muscle rupture has a poor prognosis and should be operated on soon after onset. We recently encountered a patient who was operated on 8 months after the onset of mitral regurgitation caused by rupture of the posterior papillary muscle. The patient was a 72-year-old man who was admitted as an emergency case for acute left heart failure due to severe mitral regurgitation. As medical treatment was effective, he refused to have mitral valve surgery. Six months later, he was admitted to our hospital complaining of nocturnal orthopnea and underwent surgical treatment. Severe mitral regurgitation with postero-medial papillary muscle rupture was revealed by transesophageal echocardiography. Coronary angiography showed 90% stenosis of the proximal left circumflex artery. At 8 months after the onset of mitral regurgitation, the patient underwent successful scheduled mitral valve replacement together with coronary artery bypass grafting. There are few reports of mitral valve surgery being performed successfully for papillary muscle rupture due to coronary artery disease in the chronic stage.

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A 49-year-old man was admitted to another hospital because of exertional dyspnea. He had run an entire 20-km race 33 days before admission. Echocardiograms, MRI and CT scans, and cineangiograms showed a right ventricular tumor arising from the tricuspid valve, which occupied the area from the right ventricular outflow tract (RVOT) to the pulmonary trunk and extended to the bilateral pulmonary arteries. MRI scans suggested that the tumor had not invaded the normal cardiac structure. The patient was transferred to our hospital for surgery. An operation was performed on the same day, since the tumor could have caused pulmonary embolisms. Under cardiopulmonary bypass, a right atriotomy, pulmonary arteriotomy and incision in the RVOT were made. The tumor had adhered to the chordae of the tricuspid valve, myocardium of the RVOT, and pulmonary valve. It was completely resected macroscopically. The postoperative course was uneventful and the patient was discharged on the 18th postoperative day. The size of the tumor was 2.0×2.0×10.0cm and the histological diagnosis was angiosarcoma. The patient died 4 months after the operation due to brain metastasis and local recurrence. This appeared to be a case of rapidly progressive cardiac angiosarcoma with an unusual noninvasive growth pattern.

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We report a 78-year-old man who had an impending ruptured atherosclerotic arch aneurysm combined with chronic dissecting ascending aortic aneurysm. The patient underwent a graft replacement of the ascending aorta and aortic arch using the elephant trunk method with the aid of profound hypothermia and continuous retrograde cerebral perfusion. Cerebral blood velocity was measured with transcranial Doppler (TCD) during operation. The TCD flow pattern after weaning of cardiopulmonary bypass indicated a state of brain edema. Therefore it is important in extensive retrograde cerebral perfusion to control the perfusion pressure and prevent destruction of the blood brain barrier aggressively. Pharmacological intervention could improve the safety of retrograde cerebral perfusion. Postoperative diagnostic images showed that the part of the distal anastomosis around the elephant trunk was not surrounded with thrombus. At this stage, it is not necessary to perform next extensive aortic replacement. It is important to consider the occurrence of complication, who using elephant trunk method, including paraplegia, thromboembolism, kinking of prothesis.

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