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Featured researches published by Ryuzo Bessho.


The Annals of Thoracic Surgery | 1996

Aortic dissection extending from the left coronary artery during percutaneous coronary angioplasty

Masami Ochi; Shigeo Yamauchi; Toshimi Yajima; Noriyoshi Kutsukata; Ryuzo Bessho; Shigeo Tanaka

A 72-year-old woman with acute aortic dissection as a complication of percutaneous coronary angioplasty was successfully treated. She received a graft replacement of the ascending aorta as well as triple coronary artery bypass grafts. The dissection had extended from the left coronary artery. Although acute aortic dissection is a rare complication of percutaneous coronary angioplasty, physicians and cardiac surgeons should keep its potential occurrence in mind.


The Annals of Thoracic Surgery | 2002

Efficacy of intraoperative mapping to optimize the surgical ablation of atrial fibrillation in cardiac surgery

Shigeo Yamauchi; Hidetugu Ogasawara; Yoshiaki Saji; Ryuzo Bessho; Yasuo Miyagi; Masahiro Fujii

BACKGROUND Observation during open heart surgery in patients with chronic atrial fibrillation (AF) showed that the activation sequence of the left atrium was regular and that of the right atrium chaotic in most patients. We speculate that the left atrium plays a role as an important electrical driving chamber for AF and by mapping pre-operatively, optimal sites for the cryoablation can be determined to minimize the extensiveness of the cryolesions. METHODS Forty patients who underwent cardiac surgery and cryoablation guided by epicardial mapping data to eliminate AF originating from the left atrium were included in this study. RESULTS Sustained reentrant movement or repetitive firing from foci located in the right atrium was never observed. Foci or reentry circuits located in the left atrium were clearly identified in 11 cases. Nine of the 11 cases resumed sinus rhythm by placing cryolesions at these sites. Two cases needed a pacemaker implantation. The exact site had not been identified in the 29 remaining cases. In these 29 cases a left atrial posterior longitudinal linear cryoablation was placed. Sinus rhythm resumed in 22 cases. Six cases still remained in AF and a pacemaker was implanted in 1 case. Ultimately, in this series of operations sinus rhythm was resumed in 31 of 40 cases; AF remained in 6 of them and pacemaker implantation was required in 3 cases. CONCLUSIONS Mapping was useful to distinguish the two etiologies of the AF to facilitate optimal placement of the cryolesions. Sustained reentrant movement or repetitive firing from foci located in the right atrium was never observed and the left atrium played an important role as the electrical driving chamber for AF.


The Annals of Thoracic Surgery | 2001

Adequacy of flow capacity of bilateral internal thoracic artery T graft

Masami Ochi; Nobuo Hatori; Ryuzo Bessho; Masahiro Fujii; Yoshiaki Saji; Shigeo Tanaka; Hiroshi Honma

BACKGROUND With the T graft configuration, multiple arterial revascularization can be accomplished using bilateral internal thoracic arteries. However, concern remains about the flow capacity of the main stem of the left internal thoracic artery (LITA). METHODS Forty patients who underwent multiple revascularization of the entire territory of the left coronary system with a T graft were investigated. Six months after the operation, they were examined angiographically. During the same period, dobutamine stress echocardiography was performed to evaluate the adequacy of the myocardial blood supply from the T graft. The T graft revascularized two branches in 5 patients, three branches in 23, four branches in 11, and five branches in 1 of the left coronary system. Other conduits were used if revascularization was required for the right coronary system. RESULTS Complete revascularization was achieved in the left coronary territory in all patients. The LITA main stem showed a wide lumen in all patients. Luminal narrowing was present in the distal segment of the LITA in 3 patients. The right internal thoracic artery (RITA) was patent in all patients, whereas luminal narrowing was observed in the distal segment of the RITA in 5 patients. No patient exhibited ischemic wall motion abnormality in the anteroseptal, lateral, or posterolateral region of the left ventricle where the T graft revascularized. Eight patients showed ischemic response in the inferoposterior region, that is, the territory of the right coronary artery. CONCLUSIONS The LITA main stem, forming a T-graft configuration with the free RITA, has an adequate flow reserve to supply at least the entire left coronary arterial system with sufficient blood. Therefore, multiple coronary revascularization using the T-graft technique is feasible.


Interactive Cardiovascular and Thoracic Surgery | 2010

Effect of a neutrophil elastase inhibitor on acute lung injury after cardiopulmonary bypass

Masahiro Fujii; Yasuo Miyagi; Ryuzo Bessho; Takashi Nitta; Masami Ochi; Kazuo Shimizu

Cardiopulmonary bypass (CPB) has been implicated as a cause of acute lung injury (ALI) in cardiac surgical patients. We used a bronchoscopic microsampling (BMS) probe to examine alveolar biochemical constituents and evaluated the effect of sivelestat sodium hydrate, a novel synthesized polymorphonuclear (PMN) neutrophil elastase inhibitor, on ALI induced by CPB. Twelve patients undergoing aortic valve replacement were treated with either sivelestat 0.2 mg/kg/h (sivelestat group, n=6) or 0.9% saline (control group, n=6) from the start of surgery. Samples were collected by the BMS probe at three time points: after tracheal intubation, 1 h after CPB introduction, and 3 h after CPB termination. Pulmonary function was assessed perioperatively. There were no differences in baseline characteristics. The concentration of PMN elastase was significantly suppressed in the sivelestat group, compared with the control group (P=0.001). The sivelestat group also had lower levels of interleukin-6 and interleukin-8. Alveolar-arterial oxygen difference markedly increased, and a worsening of the PaO(2)/FiO(2) ratio indicated severe impairment after CPB. However, sivelestat attenuated the pattern of physiological deterioration of gas exchange. Sivelestat may attenuate neutrophil elastase or proinflammatory cytokines, and improve pulmonary dysfunction in patients undergoing CPB.


The Annals of Thoracic Surgery | 1997

Simultaneous subclavian artery reconstruction in coronary artery bypass grafting

Masami Ochi; Shigeo Yamauchi; Toshimi Yajima; Ryuzo Bessho; Shigeo Tanaka

BACKGROUND Subclavian artery occlusive lesion, although rare, is sufficiently important to consider before coronary artery bypass grafting because it can cause not only symptoms of the lesion per se, but also the postoperative coronary-subclavian steal phenomenon. METHODS Four patients undergoing coronary artery bypass grafting received simultaneous reconstruction of the subclavian artery. During aortic cross-clamping, an 8-mm ring-reinforced polytetrafluoroethylene graft was attached to the aorta perpendicularly. The prosthetic graft was led to the proximal segment of the axillary artery through the second intercostal space and anastomosed to the inferior surface of the artery. RESULTS Three patients received unilateral reconstruction of the subclavian artery, whereas another received bilateral reconstruction. There were no complications related to the subclavian reconstruction procedure. Post-operative angiograms revealed excellent patency of the prosthetic grafts. All of the patients have been asymptomatic with follow-up periods ranging from 9 to 50 months. CONCLUSIONS To perform simultaneous subclavian artery reconstruction along with coronary artery bypass grafting, the aortoaxillary bypass procedure using an 8-mm polytetrafluoroethylene graft may be the method of choice because it has lower potential for complications and is less technically demanding.


Interactive Cardiovascular and Thoracic Surgery | 2009

Sivelestat reduces myocardial ischemia and reperfusion injury in rat hearts even when administered after onset of myocardial ischemia

Masaru Kambe; Ryuzo Bessho; Masahiro Fujii; Masami Ochi; Kazuo Shimizu

Sivelestat, a neutrophil elastase inhibitor, has been shown to attenuate pulmonary injury during ischemia and reperfusion by improving microcirculation and may be effective as a cardioprotective agent. Isolated rat hearts were Langendorff-perfused (constant pressure, 75 mmHg) with oxygenated Krebs-Henseleit bicarbonate buffer (KHB). The optimal sivelestat concentration at 19 micromol/l was revealed because left ventricular developed pressure (LVDP) recovery in 19 micromol/l sivelestat was highest among 0.19, 1.9, 19, 190, and 1900 micromol/l sivelestat (26+/-10, 33+/-7, 56+/-5*, 35+/-2, and 15+/-5%, respectively; *P<0.01). In order to examine the optimal administration timing, sivelestat was administered at pre- and post-ischemic phases. LVDP recovery and troponin-T were observed in pre-, post-ischemic sivelestat groups and control. After 60 min-reperfusion, LVDP recoveries were 42+/-10*, 45+/-19*, and 14+/-5%, respectively (*P<0.01 compared to control), and troponin-T values were 4+/-1, 2+/-1**, and 8+/-2, respectively (**P<0.05 compared to control). Acetylcholine-induced increase in coronary flow was also investigated to examine the sivelestats cardioprotective mechanism. Ischemia-reperfusion (I/R) impaired the acetylcholine-induced increase in coronary flow (maximal changes: sham, 125+/-11%; I/R, 98+/-3; P<0.01) and this impairment was attenuated by sivelestat-perfusion at reperfusion (maximal change: 112+/-7%; P<0.05 vs. I/R). Sivelestat attenuates coronary endothelial ischemia-reperfusion injury and improves myocardial protection even when administered at the reperfusion period. This suggests a role for sivelestat in the preservation of coronary endothelial function enhancing myocardial protection.


The Annals of Thoracic Surgery | 2001

Sequential grafting of the right gastroepiploic artery in coronary artery bypass surgery

Masami Ochi; Ryuzo Bessho; Yoshiaki Saji; Masahiro Fujii; Nobuo Hatori; Shigeo Tanaka

BACKGROUND Only a few studies have been done on sequential grafting using the right gastroepiploic artery (GEA). METHODS Forty patients (35 males, ages 36 to 74 years) who underwent sequential grafting of the GEA were reviewed. Angiography of the GEA was performed preoperatively in all patients. GEAs with a luminal diameter greater than 2 mm at the presumptive distal anastomosis on the angiogram were used. The dissected GEA was led into the pericardial cavity through the antegastric route. We used GEAs to graft 89 branches (2.2 per patient) in the inferoposterior region. RESULTS In 24 patients who had angiographic examinations, all the GEAs were patent, although luminal narrowing was noted in the segment between the two anastomoses in 3 patients. Eight-year actuarial survival was 92.5% and the cardiac-related event-free rate was 95%. CONCLUSIONS Sequential grafting of the GEA can be performed effectively in selected patients. Performing preoperative angiography to assess the size of the GEA for sequential grafting is strongly recommended.


The Japanese Journal of Thoracic and Cardiovascular Surgery | 2012

Choriocarcinoma of the lung: report of a case

Takayuki Ibi; Kyoji Hirai; Ryuzo Bessho; Masashi Kawamoto; Kiyoshi Koizumi; Kazuo Shimizu

In this report, a 27-year-old woman with a solitary pulmonary nodule is described. Because computed tomography-guided biopsy could not confirm the diagnosis, surgical treatment was performed by video-assisted thoracic surgery. Histological findings showed cytotrophoblasts and syncytiotrophoblasts, suggesting choriocarcinoma. However, there were no abnormal findings on gynecological examination, including ultrasonography, magnetic resonance imaging, and positron-emission tomography. Choriocarcinoma is a malignant neoplasm and can arise after a pregnancy, as a component of germ cell tumors, or in association with a poorly differentiated somatic carcinoma. Our patient, a young female with an antecedent gestation, has no recurrence after surgery. There were tumor emboli in pulmonary arteries and no component of primary lung carcinoma on histological examination. These findings indicate that the lesion was a metastasis of gestational choriocarcinoma. A rare case of a patient with metastatic gestational choriocarcinoma of a solitary pulmonary nodule without any uterine abnormality is presented.


The Annals of Thoracic Surgery | 1997

Simultaneous surgical correction of a common atrium and impure flutter

Shigeo Yamauchi; Hajime Imura; Ryuzo Bessho; Kenichi Yamada; Shigeo Tanaka

We performed surgical correction and treatment of a common atrium and chronic impure flutter using a computerized mapping system in a 49-year-old man. A reentrant circuit was observed to exist around the left atrial appendage. In contrast to the regular activation in the left atrium, the activation sequence of the right atrium was extremely chaotic. Cryolesions were applied to the area of the reentrant pathway. After the operation, sinus rhythm was restored.


Surgery Today | 1998

The Clinical Significance of Performing Preoperative Angiography of the Internal Thoracic Artery in Coronary Artery Bypass Surgery

Masami Ochi; Shigeo Yamauchi; Toshimi Yajima; Ryuzo Bessho; Shigeo Tanaka

This study was designed to clarify the clinical significance of and indications for performing preoperative internal thoracic artery (ITA) angiography in patients undergoing coronary artery bypass surgery. A total of 300 possible candidates for coronary artery bypass grafting (CABG) underwent ITA angiography during diagnostic catheterization. Semi-selective angiography of bilateral ITAs were performed by injecting contrast medium manually with a 5-F right Judkins coronary catheter. The posteroanterior view of the arteriograms was recorded on a 35-mm cine film or a cut-film. Unusual angiographic findings of the ITAs were observed in nine patients (3%). These findings included: an atrophic ITA in three patients with ipsilateral subclavian artery occlusions; enlarged ITAs giving collaterals to the lower extremities in one patient with extensive aortoiliac occlusive disease; occluded ITAs in one patient with Takayasus arteritis and two patients with a history of CABG; and a small but nonsclerotic ITA in one patient. Atherosclerotic occlusive ITAs were found in only one patient. Thus, we concluded that routine preoperative angiography of the ITA is not necessary because it is rarely affected by atherosclerosis. However, it should be performed for any of the following reasons: a cervical or supraclavicular bruit; an upper extremity blood pressure difference of greater than 20 mmHg; an extensive aortoiliac occlusion; and certain disorders such as Takayasus arteritis or Kawasaki disease, or a history of open heart surgery.

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