Since November 1999 we have attempted to use a right heart bypass (RHB) system for beating heart coronary artery bypass grafting (CABG), which system produce better exposure of lateral and posterior wall of the heart and so enable us to facilitate bypass grafting to these branches. We report on our initial clinical experience with this system and the purpose of this study is to evaluate the efficacy of this system. To clarify the efficacy of the RHB system, we compared the intraoperative and postoperative clinical course, as well as outcome, between patients who underwent beating heart CABG with RHB and patients without RHB. Seventy-seven patients underwent beating heart CABG with RHB (RHB group) between November 1999 and December 2001. In the same period, 88 patients underwent beating heart CABG without RHB. Of these latter, 30 patients needed displacement of the beating heart in order to expose target coronary arteries (OPCAB group). Perioperative clinical parameters were compared between the groups. Patients in the RHB group received more grafts (2.4±0.6) than patients in the OPCAB group (2.0±0.2, p=0.002). There were no hospital deaths in either group. While displacing the beating heart, SvO₂ decreased and pulmonary artery pressure increased in both groups. Nevertheless, the value of SvO₂ was significantly higher in RHB group while displacing to expose the circumflex region (p=0.048) and the distal right coronary artery region (p<0.01). The effect of elevation of pulmonary artery pressure in the RHB group was lower than that in the OPCAB group, but it was not statistically different. Water balance during operation was 2, 898±1, 019ml in the RHB group and the 2, 237±807ml in OPCAB group (p=0.002). Body temperature following operation was 36.0±0.8°C in the RHB group and 36.5±0.8°C in the OPCAB group (p<0.01). However, no differences were found in postoperative blood loss, required transfusion, duration of mechanical ventilation, ICU stay and hospital stay. No patient had postoperative complications related to the RHB system. The introduction of the RHB enabled bypass grafting to posterior wall vessels with better exposure and under greater hemodynamic stability. Therefore we think it a very effective support system which enable multiple coronary revascularization on beating heart CABG.

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We have studied potential for pulmonary circulational assist by the dynamic Fontan model with a skeletal muscle ventricle (SMV) constructed using the latissimus dorsi muscles of 5 dogs. After 2 weeks of vascular delay, the SMV was electrically preconditioned for 8 weeks. Under cardiopulmonary bypass (CPB), the right heart (RV) bypass model was established with the SMV anastomosed between the right atrium and pulmonary trunk. The SMV was paced at a burst frequency of 25Hz, 60/min, with an asynchronization ratio. The aortic pressure (AoP), pulmonary arterial pressure (PAP), central venous pressure (CVP), and pulmonary flow (PAF) were measured. Just after on-SMV, PAP and PAF increased, CVP decreased. CVP decreased from 17±1.4mmHg to 13.5±0.7mmHg (p<0.05). PAP increased from 20±2.8/19±1.6mmHg (non-pulsatile flow) to 37.5±4.9/18±2.1mmHg (pulsatile flow). After CPB, pulmonary vascular resistance (Rp) showed 5.9±1.5 Wood units corresponding to a high risk factor for the Fontan procedure. On this Rp, under off-SMV the CVP was 18mmHg and severe RV failure was recognized as PAF was 35% of the preoperative value. Under on-SMV, CVP decreased and PAF was almost the same as the preoperative value. On physiological CVP, an RV bypass model with intrathoracic SMV maintained PAF at the preoperative value under high Rp. We concluded that this model may be a viable surgical option for univentricular heart with high Rp, which may not be Fontan candidates.

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Though the number of reoperative coronary artery bypass grafting procedures (re-CABG) is increasing, the operative results are still inferior to primary CABG. In the present study, we analyzed results of our two different procedures for re-CABG and estimated predominance of the LAST-MIDCAB (off-pump left anterior small thoracotomy minimally invasive direct coronary artery bypass) procedure in selected patients. From 1999 to 2001, 25 patients underwent re-CABG. The age of patients ranged from 56 to 82 years (mean 70 years). Re-CABG was performed due to the occlusion of existing grafts in 14 cases, progressive disease of previously ungrafted vessels in 6 and anastomotic stenosis of previously grafted vessels in 5. We performed off-pump LAST-MIDCAB in 15 patients, on-pump CABG via a median sternotomy in 9 and on-pump LAST-CABG in 1 which was converted due to RV injury during a re-sternotomy. In the LAST-MIDCAB group, the left internal thoracic artery was chosen as a graft to the LAD in 10 patients, the right gastroepiploic artery in 4 and the saphenous vein in 1. The operation time of the LAST-MIDCAB group was significantly shorter than that of the on-pump CABG group. Blood transfusion was necessary for only one patient in the LAST-MIDCAB group. Although many postoperative complications occurred in the on-pump CABG group, no major postoperative complication was seen in the LAST-MIDCAB group except one patient who sufferred from lung fibrosis, which led to shortness of the postoperative hospital stay. We conclude that LAST-MIDCAB is an alternative way to reduce operative morbidity in selected re-CABG cases.

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Recently we reported that the inhibitor of p38 mitogen-activated protein kinase, FR-167653 (Fujisawa Pharm. Co., Ltd., Osaka) may suppress postoperative intimal hyperplasia. In this study we evaluated the best dosage and phase for administration of FR-167653, in order to clarify its mechanism in the postoperative treatment of intimal hyperplasia. Twenty-one Lewis male rats (484±5g) were studied. The epigastric vein graft was interposed into the common femoral artery. The rats were divided into four groups according to the dosage and phase of administration of FR-167653: group I (n=5) with 2.0μg/g of FR-167653 immediately before bypass, group T (n=5) with 2.0μg/g immediately before bypass and 2 weeks after bypass, group D (n=5) with 4.0μg/g immediately before bypass, and the control group (n=6) with the same dose of saline. The intimal areas of vein grafts were measured at 4 weeks postoperatively. The mean intimal areas in group I, T and D were significantly decreased compared with the control group, especially in group D (0.05±0.02mm² vs. 0.43±0.05mm², p<0.001). These results suggest that FR-167653 can suppress the postoperative intimal hyperplasia that occurs with interposition of vein grafts in rats.

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Methylprednisolone (MP) has anti-inflammatory properties. We evaluated the influence of MP on systemic inflammatory response syndrome (SIRS) in a conventional coronary artery bypass grafting (CABG) operation. We compared three groups: (1) the HD-MP group (high-dose MP group): injecting 30mg/kg MP before extracorporeal circulation, (2) the LD-MP group (low-dose MP group): injecting 5mg/kg MP, (3) the N-MP group (non-MP group): no MP injected. Postoperative SIRS duration was shorter in the HD-MP and LD-MP groups than in the N-MP group, although low-dose MP had a shortening effect on the duration of SIRS. Interleukin 6 (IL-6) and interleukin 8 (IL-8) showed lower values in the HD-MP and LD-MP groups than in the N-MP group, although low-dose MP had an inhibitory effect on the production of interleukin. However, there were no differences between the three groups in the organ protective action of MP, such as total dose of catecholamine (as an index of cardiac dysfunction), intubation period (pulmonary dysfunction), GPT/D-Bil abnormality (liver dysfunction), or BUN/Cr abnormality (renal dysfunction). The maximum value of the postoperative white blood cell count showed a higher value in the HD-MP group than in the N-MP group. In conclusion, the usage of low dose (5mg/kg) MP in a conventional CABG operation is able to shorten SIRS duration and inhibit the production of IL-6 and IL-8 without increasing the risk of infection.

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A 63-year-old man was admitted due to acute congestive heart failure. Transesophageal echocardiography demonstrated quadricuspid aortic valve malformation with concomitant severe aortic regurgitation. The valve was replaced by a 21mm Edward-MIRA and the postoperative course was uneventful. Although quadricuspid aortic valve is a rare anomaly, its potential for severe valve failure in adulthood should not be neglected.

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A 63-year-old man with unstable angina and idiopathic thrombocytopenic purpura (ITP) underwent off-pump coronary artery bypass grafting after being admitted to our hospital because of angina pectoris. Coronary angiography performed on admission showed 90% stenosis of the left main coronary artery. High dose transvenous γ globulin therapy was performed for 3 days before surgery. The number of platelets, which was 2.3×10⁴/mm³ on admission increased to 4.1×10⁴/mm³ before surgery. Ten units of platelets were transfused intraoperatively, with little perioperative hemorrhage and no increased incidence of bleeding complications. The postoperative course was uneventful. High dose transvenous γ globulin therapy and operation without cardiopulmonary bypass were useful in facilitating the treatment of this ITP coronary artery bypass patient.

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Inflammatory aneurysms of the thoracic aorta are extremely uncommon. We present a 58 year-old man with an inflammatory aneurysm of the aortic arch. He was admitted because of chest pain. Coronary angiographies showed severe stenosis of the left anterior descending artery and computed tomography revealed an aneurysm of the distal aortic arch. We conducted combined graft replacement of the aortic arch and coronary artery bypass grafting. During the operation, the patient was noted to have extensive peri-aneurysmal fibrosis and inflammation with a thick aneurysmal wall. To avoid excessive hemorrhage, distal anastomosis was performed using the graft inclusion technique. He was discharged 35 days after operation without any major complication. Pathological evaluation of the aneurysmal wall revealed destruction of the mural structure and inflammatory cell infiltration in the adventitia.

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NIPPV provides positive pressure ventilation through a face mask without intubation. We performed NIPPV for 2 patients with acute respiratory failure following cardiovascular surgery. (Case 1) A 63-year-old man, who had had COPD (Hugh-Jones class III), underwent replacement of the aortic arch. He was extubated after 5 days. However, he was re-intubated under controlled ventilation because of deterioration of his respiratory condition. The patient had NIPPV after extubation on postoperative day 14 because he was alert and had no cardiovascular compromise. On the 18th postoperative day he was weaned from NIPPV. (Case 2) A 67-year-old man underwent coronary artery bypass surgery. On the next day he was extubated, but he suffered from hypoxemia due to impaired respiratory condition on postoperative day 3. The patient underwent NIPPV instead of conventional mechanical ventilation because his condition was stable except for respiration. Respiratory condition improved quickly and he was weaned from NIPPV on the 7th postoperative day. NIPPV is an effective method for managing patients with acute respiratory failure after cardiovascular surgery.

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A 64-year-old man was transferred to our hospital because of acute heart failure associated with myocardial infarction. Echocardiography revealed severe mitral regurgitation due to total rupture of the posterior papillary muscle. Following the diagnosis of papillary muscle rupture, intraaortic balloon pumping support was started, and surgery was performed without coronary angiography because of cardiogenic shock and renal dysfunction. The posterior papillary muscle was completely ruptured, and the anterior leaflet of the mitral valve was severely prolapsed. Without resecting the posterior leaflet, mitral valve replacement was successfully performed using a St. Jude Medical^® prosthetic valve. The postoperative course was uneventful except for ventricular tachyarrhythmia which occurred during the acute phase postoperatively. Postoperative coronary angiography demonstrated no significant coronary arterial stenosis. In a patient with cardiogenic shock due to papillary muscle rupture, immediate surgical intervention is recommended as soon as the diagnosis has been established by echocardiography.

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A 75-year-old man with severe mitral valve regurgitation and 80% stenosis of the right internal carotid artery was referred to us for surgical treatment. He had a history of ipsilateral cerebral artery thrombosis 28 months previously. Although preoperative percutaneous transluminal carotid angioplasty with stenting (PTCAS) was performed, 60% stenosis of the artery still remained. He underwent mitral valve repair 2 months after PTCAS due to cardiac symptom progression. Intraaortic balloon pumping was used to maintain higher pressure during the extracorporeal circulation of the heart surgery. He recovered uneventfully and without any cerebral complications.

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A 68-year-old man was admitted to our hospital with dyspnea and general fatigue. At first, pulmonary embolism was diagnosed by electrocardiography and pulmonary scintigram. X-ray CT scans and echocardiography revealed a tumor occupying the right atrial cavity. To prevent further pulmonary embolism, he underwent tumor resection. In surgery, two venous drainage cannulas were inserted directly to the superior vena cava and to the inferior vena cava via the right femoral vein, in order to avoid the direct contact with the right atrium prior to institution of extra-corporeal circulation. The tumor was carefully removed together with the atrial wall around the site where the tumor originated. A pathological study showed that the specimens were myxoma in the right atrium. His post-operative course has been uneventful until now, however, long-term observation with respect to the metastasis and/or recurrence of this tumor will be carried out.

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A 70-year-old woman was admitted to our hospital complaining of upper abdominal pain. Computed tomography revealed a 6-cm tumor next to the inferior vena cava (IVC). Venography revealed obstruction of the IVC, and venous return was via collateral circulations. Right nephrectomy and tumor resection of the middle part of the IVC was performed. The left renal vein, which was invaded by tumor, was divided without venous reconstruction. Pathological diagnosis was leiomyosarcoma. Postoperatively hemodialysis was needed for a month, but maintenance hemodialysis was avoided. Leiomyosarcoma of the middle part of the IVC sometimes invades bilateral kidneys, and sometimes it is not possible to reconstruct the renal vein. It is important to recognize collateral circulation by preoperative angiography, and to protect such circulation during operation.

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A successfully treated case of a 73-year-old man with mycotic aneurysm of the iliac artery combined with psoas abscess was reported. The operation consisted of débridement of the infected arterial wall with arterial reconstruction using autologous reversed superficial femoral vein and wrapping the graft and filling the defects with omentum. Streptococcus pneumoniae was grown from the psoas abscess culture. He had peritonitis by gangrenous cholecystitis postoperatively and underwent reexploration for correction of the peritonitis. After his second operation, the postoperative course was uneventful. He is doing well 18 months postoperatively. Venous morbidity after superficial femoral vein harvest is minimal. In situ reconstruction with autogenous deep leg veins is a successful option in patients with mycotic aneurysms.

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Extracorporeal shock wave lithotripsy (ESWL) represents the preferred treatment for most upper ureteric and renal calculi. Complication rates associated with ESWL are low, justifying the enthusiasm and acceptance of this treatment modality. We report a case of abdominal aortic pseudoaneurysm due to ESWL. A 47-year-old man had undergone ESWL treatment for ureteric calculi since 1990. He was admitted to our hospital because of lumbar pain. Physical examination revealed a pulsatile mass in his abdomen. Abdominal CT scan showed an abdominal aortic aneurysm (5.3cm in diameter). Angiography showed a fusiform aneurysm of the infrarenal abdominal aorta. Y-graft replacement was performed after aneurysm resection. Histological examination revealed that it was a pseudoaneurysm. The patient had no history of trauma, inflammation or operation except ESWL. This is the first report of abdominal aortic pseudoaneurysm due to ESWL.

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