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Dive into the research topics where Toshiharu Yamagishi is active.

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Featured researches published by Toshiharu Yamagishi.


Journal of Heart and Lung Transplantation | 1999

Long-term heart preservation using a new portable hypothermic perfusion apparatus

Kiyohiro Oshima; Yasuo Morishita; Toshiharu Yamagishi; Jun Mohara; Toru Takahashi; Yutaka Hasegawa; Susumu Ishikawa; Koshi Matsumoto

OBJECTIVE Perfusion storage is not often used clinically compared with simple immersion because of complicated circuits and demanding management. We developed a new apparatus for preservation combined with simple immersion and continuous coronary perfusion. METHODS The main characteristics of this apparatus are as follows: (1) hypothermic storage, (2) does not require any energy source, (3) variable perfusion pressure, and (4) portability. The perfusion apparatus is composed of a storage chamber, a cooling chamber, and metal bars from which a perfusate bag is suspended. Adult mongrel dogs were divided into two groups: the coronary perfusion group (CP, n = 6) and the simple immersion group (SI, n = 6). Coronary vascular beds of the dog were washed out with a University of Wisconsin (UW) solution following cardiac arrest obtained using a GIK solution. The hearts were then excised. In the CP group, the heart graft, which was immersed in a 4 degrees C UW solution, was perfused with the same solution at a flow rate of 35 approximately 50 ml/hr. In the SI group, the heart graft was immersed in a 4 degrees C UW solution only. The heart graft was preserved for 12 hours in both groups. Beta-adenosine triphosphate (beta-ATP), phosphocreatine (Pcr), and inorganic phosphate (Pi) levels were measured immediately after excision of the heart, and at 3, 6, and 12 hours after preservation. Beta-ATP, Pcr, and Pi values were expressed as a percentage of control values, which had been obtained immediately after excision of the heart. Water content of the myocardium was measured prior to and after 12-hour preservation. The preserved graft was then evaluated through orthotopic transplantation. RESULTS Beta-ATP/Pi levels at 6 and 12 hours after preservation were significantly higher in the CP group than in the SI group (62 +/- 5 versus 39 +/- 7%, 48 +/- 5 versus 22 +/- 8%, respectively, p < 0.05). Pcr/Pi levels at 6 and 12 hours after preservation were 30 +/- 9% and 22 +/- 8%, respectively in the CP group, while Pcr/Pi levels in the SI group were detected in only one case. There was no significant difference in water content either prior to or after 12-hour preservation between the two groups. Histopathologically, irregular expansion and/or contraction of myocardial fibers were more severe in the SI group than in the CP group. The recovery rate of hemodynamic parameters 2 hours after heart transplantation was significantly (p < 0.05) higher in the CP group than in the SI group. CONCLUSION Stable and safe long-term canine heart preservation with continuous coronary perfusion associated with immersion is possible using this new apparatus, and may have broad clinical application.


Journal of Heart and Lung Transplantation | 1999

A comparative study of Celsior and University of Wisconsin solutions based on 12-hr preservation followed by transplantation in canine models.

Jun Mohara; Yasuo Morishita; Toru Takahashi; Kiyohiro Oshima; Toshiharu Yamagishi; Izumi Takeyoshi; Koshi Matsumoto

BACKGROUND Celsior is a recently developed extracellular-type preservation solution that is effective in organ preservation. This experimental study was designed to compare the effects of Celsior and University of Wisconsin (UW) solutions in myocardial protection, using 12-hour preservation followed by orthotopic transplantation. METHODS Fourteen pairs of adult mongrel dogs were divided into 2 groups. In the UW group (n = 7), UW solution at 4 degrees C was used for coronary vascular washout and storage following cardiac arrest with glucose-insulin-potassium (GIK) solution. In the Celsior group (n = 7), Celsior solution was used to produce cardiac arrest, for coronary vascular washout, and for storage. After 12-hour cold preservation, orthotopic transplantation was performed under cardiopulmonary bypass (CPB). The rate of recovery (%) of cardiac function of donor hearts was compared 1 and 2 hours after weaning from CPB, and then the transplanted hearts were harvested for histological study. RESULTS Hemodynamic parameters including cardiac output, left ventricular pressure (LVP), and the maximum rates of positive and negative increase of LVP after transplantation were significantly (p < 0.05) higher in the Celsior group than in the UW group 2 hours after weaning from CPB. The transmission electron microscopic study found that degeneration of the mitochondria in the Celsior group was less extensive than in the UW group. CONCLUSION Celsior solution enhanced the cardiac function of hearts preserved for 12 hours prior to transplantation compared to UW solution. Our results indicate that Celsior solution is equivalent or superior to UW solution for cardiac preservation.


The Japanese Journal of Thoracic and Cardiovascular Surgery | 2000

Induction of acute-phase reactive substances during open-heart surgery and efficacy of ulinastatin. Inhibiting cytokines and postoperative organ injury.

Yasushi Sato; Susumu Ishikawa; Akio Otaki; Toru Takahashi; Yutaka Hasegawa; Masao Suzuki; Toshiharu Yamagishi; Yasuo Morishita

OBJECTIVE A systemic inflammatory response after open-heart surgery using cardiopulmonary bypass may be responsible for postoperative organ dysfunction. Ulinastatin, a protease inhibitor, plays an important role in host defense under periods of stress. METHODS We studied the efficacy of ulinastatin on changes in acute-phase reactive substances during and after open-heart surgery. Patients undergoing open-heart surgery were divided into an ulinastatin group (Group U) and a control group (Group C). In Group U, we introduced 600,000 units of ulinastatin into a priming solution for cardiopulmonary bypass, 300,000 units into a cardiopulmonary bypass circuit at the removal of aortic cross-clamping, and 300,000 units a day for 5 days following surgery. RESULTS Immediately after cardiopulmonary bypass, alpha 1-antitrypsin levels decreased significantly in both groups, and increased significantly on the second day after surgery. Ulinastatin levels decreased after cardiopulmonary bypass in Group C. Significantly high levels of ulinastatin were obtained in Group U. Interleukin-6, interleukin-8, and polymorphonuclear elastase were markedly induced, and high levels of plasma concentration continued for several days after surgery. At all sample points, these concentrations in Group U tended to be lower than those in Group C. A significantly positive correlation was seen between the maximum levels of interleukin-8 and polymorphonuclear elastase, but these cytokine and polymorphonuclear elastase levels did not correlate with parameters such as the duration of anesthesia, surgery, cardiopulmonary bypass, or aortic cross-clamping. CONCLUSIONS Our study suggests that high-dose ulinastatin administration to maintain a sufficient concentration of circulating protease inhibitors may suppress overinduction of cytokines and polymorphonuclear elastase in open-heart surgery.


Journal of Heart and Lung Transplantation | 1999

Cardioprotective effects of Lazaroid U-74389G on ischemia-reperfusion injury in canine hearts.

Toru Takahashi; Izumi Takeyoshi; Yutaka Hasegawa; Tetsuya Koyano; Toshiharu Yamagishi; Kiyohiro Oshima; Koshi Matsumoto; Yasuo Morishita

BACKGROUND Lazaroid, an inhibitor of iron-mediated lipid peroxidation, has been shown to reduce free radical-mediated injury after ischemia and reperfusion. The effect of Lazaroid U-74389G was investigated on ischemia-reperfusion injury of the heart through preservation and transplantation (Tx) in dogs. METHODS Eleven pairs of adult mongrel dogs weighing 8.5 to 12 kg formed the recipient-donor combinations. Following electromechanical arrest of the heart using cardioplegia, the coronary vascular beds were washed out with a cold University of Wisconsin solution followed by 12-hour preservation and orthotopic Tx. Experimental animals were divided into 2 groups; 6 pairs formed the control group, and 5 formed the Lazaroid-treated group in which Lazaroid U-74389G at 10 mg/kg was administered intravenously 30 minutes before reperfusion of the heart. The cardiac function including cardiac output, left ventricular (LV) pressure, and LV dp/dt was assessed 2 hours after Tx by comparing it with the recovery rates (%) from cardiac function of donor dogs. Each transplanted heart was harvested for histological study. RESULTS The recovery of cardiac function after Tx was significantly better in the Lazaroid-treated group than in the control group. Histologically, myocardial damage, evaluated by both light and transmission electron microscopy, was less evident in the Lazaroid-treated group than in the control group. CONCLUSION Early cardiac function following Tx was significantly better and histological damage was less in the Lazaroid-treated group than in the control group, suggesting that Lazaroid U-74389G is effective in preventing ischemia-reperfusion injury after preservation and Tx.


Surgery Today | 1996

SUCCESSFUL CORONARY ARTERY BYPASS GRAFTING FOR A PATIENT WITH MYELODYSPLASTIC SYNDROME : REPORT OF A CASE

Toshiharu Yamagishi; Katsuo Fuse; Tsutomu Saito; Morito Kato; Yoshio Misawa; Osamu Kamisawa; Takahisa Kawashima

We report herein the case of a 61-year-old man with myelodysplastic syndrome causing pancytopenia who underwent successful coronary artery bypass grafting (CABG). Preoperatively, his hemoglobin (Hb) value was 10.4 g/dl while receiving transfusions of 1 or 2 units of red blood cells (RBC) every 2 weeks, his white blood cell (WBC) count was 8200/μl with injections of 100 μg granulocyte colony-stimulating factor (G-SCF) every 5 days, and his platelet count was 4.5×104/μl without platelet transfusion. From the time the pancytopenia was diagnosed in his peripheral blood, he had received a total of 104 units of RBC and 472 units of platelets, following which he developed an antiplatelet antibody, not for a platelet-specific antigen, but for an HLA antigen. Thus, HLA-matched platelets were prepared to prevent bleeding caused by thrombocytopenia, and the WBC count was elevated preoperatively by G-CSF injections. Thereafter, CABG was performed on three vessels. The HLA-matched platelets were transfused as the patient was weaned from the extracorporeal circulation. As a result of these preparations, we were able to protect the patient against bleeding and infection.


Surgery Today | 2004

Clinical results of extracorporeal membrane oxygenation (ECMO) support for acute respiratory failure: a comparison of a centrifugal pump ECMO with a roller pump ECMO.

Toshiharu Yamagishi; Fumio Kunimoto; Yukitaka Isa; Hiroshi Hinohara; Yasuo Morishita

PurposeThe purpose of this study was to compare the clinical results of extracorporeal membrane oxygenation (ECMO) using a centrifugal pump (CP group) and that using a roller pump (RP group) for the treatment of acute respiratory failure (ARF).MethodsFrom November 1990 to July 2001, the ECMO system was introduced for the treatment of 15 patients with ARF; 10 cases of pneumonia or adult respiratory distress syndrome (ARDS), 4 cases of pulmonary hemorrhage, and 1 case of hypoxemia following cardiac surgery. Five patients were included in the RP group, and 10 were included in the CP group.ResultsThe mean PaO2/FIO2 ratio, PaCO2 prior to ECMO induction, and the mean duration of ECMO support were 59.8, 38.8 mmHg, and 125 h, respectively, in the RP group, and 65.6, 82.0 mmHg, and 107 h, respectively, in the CP group. The mean PaCO2 value was significantly (P ≪ 0.05) higher in the CP group than in the RP group due to the ventilation with “permissive hypercapnia.” In the RP group, all patients died of either complications or recurrence due to ARF. In the CP group, 3 patients including 2 with pulmonary hemorrhaging were discharged.ConclusionsAlthough the centrifugal pump ECMO improved the clinical results of ARF, the overall prognosis nevertheless depended on the original disease.


Surgery Today | 1999

Postoperative brain complications following retrograde cerebral perfusion

Yasushi Sato; Susumu Ishikawa; Akio Otaki; Toru Takahashi; Yutaka Hasegawa; Tetsuya Koyano; Toshiharu Yamagishi; Satoshi Oki; Yasuo Morishita

This study was undertaken to investigate the neurological risk factors associated with the retrograde cerebral perfusion (RCP) technique, by examining the relationship between intraoperative parameters and postoperative brain complications. A total of 12 patients who underwent surgery for thoracic aortic aneurysms using the RCP technique were included in this study. Profound hypothermia was induced through cardiopulmonary bypass which was established with a femoral arterial cannula and bicaval return. During RCP, a venous drainage cannula from the superior vena cava (SVC) was switched over to the arterial return circuit, and oxygenated blood was retrogradely infused through the SVC. The perfusion flow rate was maintained at 273 ± 113 ml/min and the SVC pressure was maintained at 15 ± 6mmHg. The RCP time was 68 ± 27 min with a range of 27–130 min, and the lowest rectal temperature was 16 ± 1°C. The total elapsed time until emergence from anesthesia after the operation was 12 ± 6h. The operation time correlated with the awakening time (r=0.729,P=0.0088). Longer RCP times of up to 101 and 130min tended to result in postoperative brain damage. The lowest rectal temperature also correlated with the awakening time (r=0.697,P=0.0149), and an inverse correlation between the SVC pressure and the awakening time was observed (r=−0.727,P=0.0091). These findings demonstrate the importance of reducing both the RCP and operation times to decrease the incidence of brain damage. If carried out under optimal conditions, including perfusion pressure and brain temperature, RCP could be marginally prolonged safely without causing major neurological complications.


The Japanese Journal of Thoracic and Cardiovascular Surgery | 1998

Postoperative infections related to pacing wires, pulmonary Arterial catheters, and drainage tubes temporarily Inserted during open-heart surgery

Motoi Kanoh; Susumu Ishikawa; Masao Suzuki; Akio Otaki; Toru Takahashi; Yasushi Satoh; Tetsuya Koyano; Yutaka Hasegawa; Toshiharu Yamagishi; Yasuo Morishita

Bacterial examinations of temporary pacing wires (P-wires), pulmonary arterial (P-A) catheters, and drainage tubes temporarily inserted during open-heart surgery were performed in 213 patients. Bacteria were detected in 19 (2.8%) of 672 specimens gathered from the subject patients, with coagulase-negative Staphylococcus (CNS) being most frequently observed. P-wires accounted for 17 out of 19 of the culture-positive specimens, and 7 of the P-wires remained in place for more than two weeks. The frequency of infection with the P-wires was significantly higher than with the P-A catheters or drainage tubes. The period of time that the P-wire was left in place significantly longer than for P-A catheter or drainage tube. There was, however, no statistically significant difference between the culture-positive and negative groups in respect to age, detention periods, operation times, CPB times, or length of ICU stay. As a result of these findings, we have concluded that P-wires should be removed as soon as possible following surgery, and in any case, a meticulous care should be taken to prevent transcutaneous infection.


Surgery Today | 1997

Thoracoscopic Closure of a Congenital Partial Pericardial Defect

Toshiharu Yamagishi; Susumu Ishikawa; Ichiro Yoshida; Akio Ohtaki; Toru Takahashi; Satoshi Ohki; Shuji Sakata; Yasuo Morishita

We describe our technique for performing direct thoracoscopic closure of a congenital partial pericardial defect, which was successfully employed in a 15-year-old boy. This is the first such report of a procedure that is noninvasive and may therefore become the treatment of choice for patients with a small congenital pericardial defect.


Surgery Today | 2007

Large Organized Thrombus of the Tricuspid Valve: Report of a Case

Toshiharu Yamagishi; Kazuhiro Sakata

We report the case of a 49-year-old woman with a large organized tricuspid valve thrombus in a structurally normal heart. Preoperative echocardiogram showed a large irregular-shaped mass, approximately 5 cm in diameter, moving from the right atrium into the right ventricle. The assumed preoperative diagnosis was cardiac metastasis of uterine sarcoma because she had undergone surgery for uterine sarcoma 15 years earlier. However, histologic examination revealed an organized thrombus without tumor components.

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