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Biomedical subjects

K Kotoh

Publications and source records attributed to K Kotoh.

At least 37 records · Page 2Linked to original sources
PubMed1999

Multiple minimally invasive direct coronary artery bypass grafting for the complete revascularization of the left ventricle.

BACKGROUND: Single-vessel coronary artery bypass grafting of the left internal mammary artery to the left anterior descending coronary artery using a minithoracotomy has been shown to produce excellent results with a very low mortality rate. However, this procedure cannot be used in patients with double- or triple-vessel disease. Our goal was to develop a minimally invasive direct coronary artery bypass grafting without cardiopulmonary bypass for total revascularization of the left ventricle using multiple arterial grafts. METHODS: Limited lateral thoracotomy was performed in the fourth or fifth intercostal spaces, exposing the left anterior descending coronary artery and left circumflex coronary artery. Two or three arterial grafts were harvested. Revascularization of the left anterior descending coronary artery and the left circumflex coronary artery were performed in 20 patients without cardiopulmonary bypass through the limited lateral thoracotomy using complex performed arterial grafts. In 4 patients, triple- and quadruple-vessel grafting was performed. RESULTS: The mean coronary cross-clamp time was 14.5+/-4.0 minutes for the left anterior descending coronary artery and 16.8+/-5.1 minutes for the left circumflex coronary artery. No early deaths or postoperative complications occurred. There were no late deaths or angina during the mean follow-up of 7.0 months (range, 2 to 22 months). Postoperative coronary angiography demonstrated widely patent grafts in all patients. CONCLUSIONS: Minimally invasive approach through a limited thoracotomy in multiple coronary artery bypass graftings are technically feasible and may be an alternative approach in the complete revascularization of the left ventricle. Mechanical immobilization of the coronary artery enhances early graft patency and is an essential part of this procedure.

Aged↗
PubMed1999

On-line assessment of regional ventricular wall motion by transesophageal echocardiography with color kinesis during minimally invasive coronary artery bypass grafting.

OBJECTIVE: Our objective was to determine the changes in regional ventricular wall motion during minimally invasive direct coronary artery bypass grafting by color kinesis using transesophageal echocardiography. METHODS: Minimally invasive coronary artery bypass grafting was performed in 34 patients, during which transesophageal echocardiography was used. Thirteen patients had isolated disease of the left anterior descending artery. Regional ventricular wall motion was analyzed by color kinesis with the SONOS 2500 transesophageal echocardiograph (Hewlett-Packard Co, Andover, Mass). On-line assessment of regional wall motion was continued during the operation. RESULTS: Wall motion abnormalities during ischemia were present in 4 cases, left ventricular mid-anterior hypokinesis in 3 cases, and left ventricular apical-lateral hypokinesis in 1 case. In all cases, wall motion was maintained after bypass. In patients with total coronary occlusion, changes in wall motion did not occur during anastomosis. CONCLUSIONS: Color kinesis allowed us to evaluate the change in regional ventricular wall motion induced by myocardial ischemia during minimally invasive coronary artery bypass grafting both objectively and quantitatively.

Aged↗
PubMed1999

Soluble Arg-Gly-Asp peptides reduce collagen accumulation in cultured rat hepatic stellate cells.

Hepatic stellate cells play a central role in the pathogenesis of liver fibrosis, both via production of extracellular matrix proteins and through secretion of matrix metalloproteinases. In this study, effects of soluble cell adhesion peptides on collagen type I accumulation and on expression of matrix metalloproteinases were analyzed. First, we revealed the expression of alpha5-integrin on hepatic stellate cells by immunostaining. Treatment with 100 microg/ml of soluble Arg-Gly-Asp (RGD) peptides was found to reduce accumulation of type I collagen without any effects on its transcriptional level in rat hepatic stellate cells, whereas a control peptide Gly-Arg-Gly-Glu-Ser (GRGES) had no such effect. Soluble RGD peptides also increased the secretion of collagenase by stellate cells. These data suggested that reduced accumulation of type I collagen caused by the RGD peptide ligation to integrins on hepatic stellate cells was partly due to stimulated expression of collagenase by stellate cells.

Animals↗
PubMed1999

[A case of surgical resection of metastatic multiple lung pheochromocytoma with long-term survival].

A case of resection of metastatic multiple lung malignant pheochromocytoma is presented. Seven years before, total resection of the right adrenal gland and the right kidney was performed to remove a pheochromocytoma. During the post-surgical observation in the urology outpatient clinic, the blood noradrenalin concentration increased and multiple lung metastatic nidi were observed by chest X-ray. An excision was made to remove 3 wedge-shape metastatic nidi from both lungs. In the third year after the removal of the pulmonary metastatic nidi, a resection was again performed due to recurrence in the left retroperitoneal lymph node. Another recurrence was found in the S6 liver 1 year after the removal of the lymph node, and TAE and PEIT were conducted. When the recurrent metastatic nidi were found, the blood noradrenalin concentration was elevated, and it normalized after treatment. In this case, careful and long-term observation including monitoring the blood noradrenalin concentration in the outpatient clinic and positive surgical treatment proved effective. The patient is currently in good health without signs of recurrence 12 years after the removal of the primary adrenal nidus and 6 years after the removal of the pulmonary metastatic nidus.

Adrenal Gland Neoplasms↗
PubMed1998

Pathological Analysis of the Radial and Internal Thoracic Artery.

To evaluate the usefulness of the radial artery (RA) as a graft material for coronary artery bypass grafting (CABG), histologic studies of the RA were performed and compared with the internal thoracic artery (ITA). Specimens were obtained from both ends of 12 RAs and the distal side of the ITA during the operation. The degree of arteriosclerosis was evaluated using an NIH Image 1.57 system. The pathological index of arterioslerotic change was expressed as the ratio of cross-section (Rx: internal luminal area/tunica media area). The mean arteriosclerotic ratio (Rx) of the 12 proximal sides of the RA specimens was 0.18 +/- 0.03, the 12 distal sides 0.27 +/- 0.17, and the 12 ITAs was 0.14 +/- 0.05, respectively. There was significant difference between the distal side of the RA and the ITA. The distal side of the RA was a little greater than the proximal, but there was no significant difference between the proximal side of the RA and the ITA. From the microscopic findings, the tunica media of the RA is poor in elastic fibers and rich in smooth muscle cells compared with the ITA. The internal elastic lumina of the RA is developed as well as the ITA, but more calcification was found in the distal RA than in the others. According to these results, although care must be taken for arteriosclerosis of the distal RA, it can be expected to be a suitable bypass material for CABG.

Journal Article↗
PubMed1998

Bilateral thoracoscopic minimally invasive direct coronary artery bypass grafting using internal thoracic arteries.

BACKGROUND: Single-vessel coronary artery bypass grafting of the left internal mammary artery (ITA) to the left anterior descending coronary artery using a minithoracotomy has been shown to produce excellent results with a very low mortality. However, this procedure cannot be used in patients with double- or triple-vessel disease. Our goal was to develop a minimally invasive direct coronary artery bypass grafting procedure without cardiopulmonary bypass for patients with multivessel disease. METHODS: Both ITAs were thoracoscopically harvested using video imaging. Limited bilateral anterior thoracotomies were performed in the fourth intercostal spaces, thus exposing the right coronary artery and the left anterior descending coronary artery. The right ITA-right coronary artery and ITA-left anterior descending coronary artery anastomoses were performed without cardiopulmonary bypass using 8-0 polypropylene sutures. RESULTS: This procedure was successfully performed in 3 patients. The patients were extubated in the operating room. Postoperative angiographic studies showed patent left ITA and right ITA grafts. CONCLUSIONS: Bilateral thoracoscopic minimally invasive direct coronary artery bypass grafting can be used to treat patients with a proximally diseased left anterior descending coronary artery and right coronary artery. Bilateral thoracoscopic ITA harvesting is a less invasive surgical technique that may become an option for the management of multivessel coronary artery disease.

Aged↗
PubMed1998

Ectopic thymoma mimicking diffuse pleural mesothelioma: a case report.

A case of ectopic thymoma of the pleura with a particular growth pattern mimicking diffuse pleural mesothelioma is reported. Diagnostic imaging showed that the pleural tumor encased the entire left lung. The specimen biopsied from the tumor was composed of lymphocytes and epithelial cells, consistent with the mixed type of thymoma. The autopsy found no evidence of a mediastinal tumor. An involuted thymus was found in the parietal pleural tissue adhered to the apex of the left lung. The thymoma was thought to originate from the ectopic thymic tissue in the parietal pleura, as a lesion independent from the primary mediastinal thymoma, and spread along the pleura like diffuse mesothelioma.

Adult↗
PubMed1998

Intradural spinal hibernoma: case report.

BACKGROUND: Hibernoma is a rare, benign tumor arising from vestigial remnants of brown adipose tissue. It usually affects muscle and subcutaneous tissue and is asymptomatic and slow growing. METHODS: A review of the worldwide literature contains about 110 cases of hibernomas. However, only two cases (including our case) of hibernoma located in the intradural spine have been reported. We present an extremely rare case of intradural extramedullary spinal hibernoma and summarize the magnetic resonance imaging (MRI) findings of the lesion. CASE DESCRIPTION: A 35-year-old woman suffered from motor weakness and numbness of the left upper extremity. Cervical spinal MRI revealed an intradural extramedullary mass at C7. She underwent surgery via the posterior approach and the lesion was completely removed. Histopathologic examination showed multivacuolated cells with centrally placed nuclei, and the diagnosis of hibernoma was made. CONCLUSIONS: Because the CT and MRI findings of hibernoma are almost same as those of other lipomatous tumors, a surgical specimen of this tumor is necessary to establish the correct diagnosis. Early diagnosis and total resection are necessary as some cases showed malignant features or rapid growth. Etiologically, the tumor may have developed by the ectopic growth or migration of adipose tissue.

Adult↗
PubMed1998

[Minimally invasive direct coronary artery bypass grafting (MIDCAB) for right and circumflex coronary artery systems].

BACKGROUND: Single-vessel coronary bypass grafting of the left internal thoracic artery (LITA) to the left anterior descending coronary artery (LAD) with mini-thoracotomy has been shown to produce excellent results with almost no mortality. However this procedure cannot be used in patients with double or triple vessel disease. METHODS: Between Aug. 96 and Dec. 97, 17 pts underwent minimally invasive direct coronary artery bypass (MIDCAB) to right (RCA) and circumflex coronary artery (CX). LITA and RITA were thoracicscopically harvested and the right gastroepiploic artery (RGEA), inferior epigastric artery, and radial artery were then harvested. A limited left thoracotomy in combination with limited anterior right thoracotomy (n = 3) or right lower parasternal incision extending to below the xiphoid process (n = 6) were made. The double MIDCAB as performed in 16 pts and triple in 1 pt. RESULTS: There was no operative death. At follow up, all pts are alive and well. The postoperative angiographic studies showed 30/31 grafts were patent. CONCLUSION: The utility of multi-vessel MIDCAB for the LAD, CX and RCA with in-site arterial grafts has been demonstrated in the present study. This less invasive surgical technique may become a viable option for the management of multi-vessel coronary artery disease.

Aged↗
PubMed1998

Cryopreserved ascending aortic homograft for Stanford B dissecting aneurysm.

A 68 year-old woman underwent replacement of the descending thoracic aorta with a cryopreserved aortic homograft for the treatment of a Stanford B dissecting aneurysm. After surgery, the patient made an uneventful recovery without recurrent infection. In such cases, the use of aortic homografts to replace aortic segments is a promising and effective therapeutic option.

Aged↗
PubMed1997

Multiple intramedullary spinal sarcoidosis: case report.

BACKGROUND: According to past reported cases, spinal intramedullary sarcoidosis has the radiologic characteristics of a single enhanced lesion with cord swelling. However, it is difficult to make a diagnosis using only radiologic examinations. Including our case, 20 cases have been reported of intramedullary spinal sarcoidosis. Only six cases were diagnosed as primary spinal sarcoidosis. We present a rare case of multiple spinal intramedullary sarcoidosis without cord swelling. CASE DESCRIPTION: This 63 year-old man was afflicted with progressive paraparesis and numbness of the lower extremities. Magnetic resonance imaging showed intramedullary lesions without cord swelling. The patient underwent biopsy for diagnosis and the specimen showed a noncaseating granuloma mainly composed of epitheloid cells. Postoperative corticosteroid therapy was effective and the lesion disappeared 1 month after the operation. CONCLUSIONS: Biopsy is a less invasive method and is useful for early diagnosis. Early diagnosis is important for spinal sarcoidosis so that high-dose corticosteroid therapy can be commenced while the lesion still has a good chance of being successfully treated.

Humans↗
PubMed1997

Inhaled nitric oxide after lung ischemia reperfusion; effect on hemodynamics and oxygen free radical scavenger system.

OBJECTIVE: Pulmonary hypertension and transient graft dysfunction may complicate the postoperative course of patients undergoing lung transplantation. Recent studies have suggested that ischemia followed by reperfusion impairs release of endothelium-derived nitric oxide (NO). We investigated the acute effect of inhaled NO on hemodynamics and the oxygen free radical scavenger system after reperfusion following lung ischemia. METHODS: Fourteen anesthetized mongrel dogs were ventilated mechanically. After median sternotomy the left lung was rendered ischemic by totally clamping the left pulmonary hilum. After 90 min, the left lung was reperfused for 150 min by unclamping of the left hilum and clamping the right pulmonary hilum so that all pulmonary blood flow was directed to the left lung. Seven dogs inhaled 30 parts per million (ppm) NO during reperfusion (NO group); the other seven dogs were ventilated without NO inhalation (control group). Hemodynamics, gas exchange, superoxide dismutase activity and lipid peroxide of pulmonary venous blood, and wet/dry ratio of reperfused lung were measured. RESULTS: Neither of the two groups showed any change in systemic blood pressure prior to or following reperfusion. Immediately after reperfusion, mean pulmonary arterial pressure was significantly less (23.2 +/- 4.2 mmHg) in the NO group than in the control group (32.7 +/- 5.8 mmHg), as had been throughout reperfusion. Pulmonary vascular resistance and right ventricular end diastolic pressure were lower after reperfusion in the NO group. Superoxide dismutase activity after reperfusion in the control group significantly decreased to 41% of preischemic value. In the NO group, however, no decrease was seen and a significantly higher value was observed. The wet/dry ratio of reperfused lung was 5.47 +/- 0.52 in the control group and 4.72 +/- 0.36 in the NO group, with decreased pulmonary moisture noted in the NO group. There was no difference in lipid peroxide between the two groups. CONCLUSION: NO inhalation suppressed pulmonary hypertension after reperfusion following lung ischemia without affecting systemic arterial pressure. As superoxide dismutase activity was not depressed in the NO group, NO inhalation might enhance suppression of oxygen free radicals. These findings suggest that NO inhalation may be therapeutically useful after lung transplantation.

Administration, Inhalation↗
PubMed1997

[Minimally invasive direct coronary artery bypass grafting (MIDCAB) without cardiopulmonary bypass: a case report].

A new coronary artery bypass grafting of the left anterior descending coronary arteries (LAD) with in situ internal thoracic artery (ITA) bypass grafts through a limited anterior thoracotomy was performed in a 70-year-old [correction of 60] patient. The left ITA-LAD anastomosis was completed without cardiopulmonary bypass and postoperative angiography showed a patent anastomosis. With this minimally invasive approach, the procedure should provide the benefits of ITA grafting with rapid recovery short hospital stay without complication associated with cardiopulmonary bypass in selected cases.

Aged↗