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Yoshimasa Sakamoto Kazuhiro Hashimoto Hiroshi Okuyama Shinichi Ishii Takahiro Inoue Katsushi Kinouchi Takayuki Abe 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(9):465-469
Objective The objective of the present study was to compare long-term results of single aortic valve replacement (AVR) with mechanical
(St. Jude Medical valves: standard) and biologic (the Carpentier-Edwards pericardial) prostheses. Method: Between 1995 and 2002, 95 patients who underwent single AVR with mechanical (n=46) or biologic (n=49) prostheses were enrolled
in this study. The mean age at the operation was 54.0±9.6 years (range: 20 to 69 years) with the mechanical and 68.8±7.1 years
(range: 44 to 85 years) with the biologic prosthesis. Results: The 9-year actuarial survival rate, which was calculated by taking perioperative mortality into account, was 90.3±4.6% for
patients with mechanical valves and 87.6 ±4.8% for patients with bioprostheses, with no difference between the two groups
(p=0.342). The 9-year freedom rate from thromboembolism, reoperation, endocarditis was 94.8+3.6%, 100% and 97.8 ±2.2% for
patients with mechanical valves and 98.0 ±2.0%, 97.5 ±3.4% and 95.0 ±3.4% for those with bioprostheses, respectively. After
9 years, freedom from cardiac death averaged 97.8% in the group with mechanical valves compared with 95.3% in those with bioprostheses
(p=0.541). Conclusion: We conclude that the mid-term durability of the Carpentier-Edwards pericardial valve in the aortic position for the elderly
is excellent. Nevertheless, the risk of tissue valve reoperation progressively increases with time, and a longer follow-up
may be necessary to provide its value compared with the mechanical valves in a country like Japan with a high life expectancy.
(Jpn J Thorac Cardiovasc Surg 2005; 53:465-469) 相似文献
3.
Osamu Yokota Kuniaki Tsuchiya Yoshimasa Noguchi Hisamasa Akabane Hideki Ishizu Yukinobu Saito Haruhiko Akiyama 《Neuropathology》2007,27(6):539-550
We report a case of a 68‐year‐old right‐handed man with sporadic amyotrophic lateral sclerosis (ALS) and argyrophilic grain disease (AGD) having a 22‐month duration. His initial symptoms were dysarthria and swallowing difficulty at the age of 67. Subsequently bulbar palsy and pyramidal signs developed. His cognitive functions including face recognition, personality, and behavior were not changed compared with that of before the disease onset. However, magnetic resonance imaging disclosed severe right side‐predominant temporal atrophy. The neurological diagnosis was bulbar type ALS. Pathological examination disclosed histological evidence of ALS, including loss of Betz cells and lower motor neurons, corticospinal tract degeneration, and Bunina bodies. In addition, severe neuronal loss in the bilateral temporal cortex with an anterior gradient was found. Ubiquitin‐positive inclusions were encountered in the spinal anterior horn cells and hippocampal dentate gyrus, while few ubiquitin‐positive inclusions were noted in the affected temporal cortex. The amygdala, especially the basolateral nuclear group, was severely affected by neuronal loss with tissue rarefaction. Moderate neuronal loss was encountered in the parahippocampal gyrus, and to a lesser degree, in the ambient gyrus. Unexpectedly, many argyrophilic grains, coiled bodies, tau‐positive bush‐like astrocytes, pretangles, and ballooned neurons were found in the limbic system and temporal cortex. In the hippocampus, selective tau accumulation with minor neurofibrillary changes was observed in CA2 neurons. The present case suggests that (i) ALS and AGD do rarely coexist, and (ii) when ALS patients have severe temporal atrophy, not only ALS with dementia but also concurrent AGD should be considered in the differential diagnosis. 相似文献
4.
Hiroomi Murayama Masanobu Meda Ken Miyahara Yoshimasa Sakai Hajime Sakurai Hiroki Hasegawa Akemi Kawamura 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2003,51(3):91-97
Objective: We assessed the current role of preoperative and intraoperative autologous blood donation in pediatric open-heart surgery.
Methods: Group 1 consisted of 51 patients between 5 and 10 years old who underwent preoperative autologous blood donation. Group
2 consisted of 50 age-matched patients without preoperative donation as controls. Intraoperative donation was conducted in
both groups prior to cardiopulmonary bypass. We evaluated perioperative blood cell count, blood loss, and the need for homologous
blood products. Results: No serious complications occurred in preoperative or intraoperative donation. Total preoperative donation storage was 17.5±3.4
mL/kg. Intraoperative donation was 21.7 ±6.1 mL/kg in Group 1 and 12.8±4.0 mL/kg in Group 2 (p<0.001). On admission, serum
hemoglobin was lower in Group 1 (12.2±1.0 g/dL versus 13.6±1.6 g/dL, p<0.001) but returned postoperatively to the preoperative
value. It hovered at a depressed level in Group 2 (12.2±1.4 versus 10.2±1.1 g/dL, p<0.001). The homologous blood requirement
was significantly less in Group 1 than in Group 2 (0% versus 10%, p<0.05). Postoperative platelet counts showed similar curves,
and blood loss was not statistically significantly different between groups. Conclusion: Preoperative and intraoperative donations are safe and continue to contribute uniquely to blood conservation, providing
important options in comprehensive blood conservation programs in current pediatric open-heart surgery. 相似文献
5.
Yuji Sugawara Kazumasa Orihashi Kenji Okada Kazuhiro Kochi Katsuhiko Imai Taijiro Sueda 《Annals of thoracic and cardiovascular surgery》2003,9(3):202-205
In Takayasu's arteritis (TA), both atypical coarctation (CO) and brachiocephalic involvement are common features that occasionally require operative correction. A combination of these abnormalities could duplicate underlying illness in patients, posing an increased risk of operative morbidity. We present, herein, two TA patients in which hypertensive heart disease secondary to CO was surgically corrected. Both patients had multi-vessel brachiocephalic disease. One patient who showed occlusion of all brachiocephalic arteries underwent aorto-aortic bypass, while another with two-vessel lesion underwent axillo-bifemoral bypass grafting. Subclavian reconstruction was supplemental to each procedure, resulting in relief of neurologic stigmata. Strategies to avoid intraoperative cerebral ischemia played an important role in the surgical repair of such TA-related extensive vascular lesions. 相似文献
6.
7.
Eichi Itadera Yoshimasa Miyake Yoichi Nakatsuka Hirofumi Akazawa Shigeru Mitani Kiyoshi Aoki 《Journal of orthopaedic science》1996,1(4):252-258
We report satisfactory results with a new operative treatment, conducted via an extensive anterolateral approach, involving
360 degree circumferential capsulotomy, for residual subluxation in congenital dislocation of the hip (CDH). Long-term radiographic
results of this procedure (group A) were compared retrospectively with the results of partial capsulotomy (group B), which
preserved the posteroinferior joint capsule. The mean center edge angle in group A (22.5°) was greater than that in group
B (16.0°). Satisfactory results were achieved in 11 of 15 hips (73%) (Severin class I or II) in group A, and in 5 of 12 hips
(42%) in group B. These results suggest that whole circumferential capsulotomy can remove obstacles to complete reduction,
and that acetabular development can be expected in hips reduced by the procedure, without the performance of innominate osteotomy.
We believe that our technique is a useful alternative for the treatment of residual subluxation in CDH. 相似文献
8.
Yoshimasa Mori Masakazu Takayasu Yoshio Suzuki Masato Shibuya Jun Yoshida Hiroyoshi Hidaka 《European journal of pharmacology》1997,320(2-3):183-186
The vasodilator effects of C-type natriuretic peptide (CNP) were investigated in isolated rat cerebral arterioles. CNP caused dose-dependent vasodilation, maximally by 10.0±2.2% at 10−6 M. The median effective concentration (EC50) was 5.2×10−10 M. In contrast, atrial natriuretic peptide and B-type natriuretic peptide, other members of the natriuretic peptide family, produced little or no vasodilation. Pretreatment with methylene blue (10−4 M) abolished CNP-induced vasodilation, whereas pretreatment with NG-monomethyl--arginine or indomethacin did not inhibit vasodilation. Thus, CNP is suggested to cause significant vasodilation in cerebral arterioles via a cyclic guanosine monophosphate-dependent mechanism. © 1997 Elsevier Science B.V. All rights reserved. 相似文献
9.
10.
Near-infrared spectroscopy for monitoring cerebral ischemia during selective cerebral perfusion. 总被引:3,自引:0,他引:3
Kazumasa Orihashi Taijiro Sueda Kenji Okada Katsuhiko Imai 《European journal of cardio-thoracic surgery》2004,26(5):907-911
OBJECTIVE: To minimize the neurological complications following cardiovascular surgery, it is essential to prevent an occurrence of cerebrovascular embolism and to detect and solve cerebral malperfusion without delay in the operating theater. Although we have introduced near-infrared spectroscopy (NIRS) monitoring for the purpose of detecting cerebral malperfusion, no criterion has been available. We searched for this criterion by examining the relationship of sustained drop in the regional oxygen saturation (rSO2) of the frontal lobes to the occurrence of neurological events. METHODS: The 59 consecutive patients undergoing aortic surgery with selective cerebral perfusion (SCP) were examined. The rSO2 was monitored throughout the surgery and the durations of drops in rSO2 to below 55% and those below 60% were determined for each patient. The durations of rSO2 drop and other surgery-related parameters were compared between the patients in whom neurological events occurred and those without such events. RESULTS: A total of 16 cases (27.1%) presented with neurological events. Newly developed cerebral infarction was documented in 6 of these 16 cases. Operation time and the durations for which rSO2 dropped were significantly longer for the 16 patients with neurological events than for the 43 patients without events (Op time: 546.8 versus 448.1 min, P=0.0064; rSO2 below 60%: 141.2 versus 49.8 min, P=0.0032; rSO2 below 55%: 66.6 versus 10.6 min, P=0.0011), while there was no significant difference in age, bypass time, aortic clamping time, SCP time, and circulatory arrest time between the two groups. In the 3 patients with infarcts suggestive to hypoperfusion, sustained decrease in rSO2 was observed, while it was not significant in the remaining 3 patients with infarcts suggestive to embolism. Among the 53 patients without infarction, transient neurological events occurred more frequently in patients with sustained drop in rSO2 below 55% for over 5 min (44.4% versus 5.7%, P=0.0014). CONCLUSIONS: A sustained drop in rSO2 during aortic surgery is closely related to the occurrence of neurological events following surgery. We recommend that recovery of drop in rSO2 below 55% should be addressed without delay. However, use of NIRS is limited for detecting embolic events or hypoperfusion in the basilar region. 相似文献