Biomedical subjects

Yoshiharu Takahara

Publications and source records attributed to Yoshiharu Takahara.

8 recordsLinked to original sources

PubMed2006

Ascending aortic aneurysm following aortico-ventricular tunnel repair.

Aortico-left ventricular tunnel is a very rare congenital anomaly. An 18-year-old boy had undergone tunnel closure at 3 years of age. A moderate degree of aortic regurgitation remained postoperatively. Seven years later, aortic valve replacement for aortic regurgitation was performed. Eight years later, the ascending aortic aneurysm had grown to 63 mm in diameter. This dilatation became an operative indication. Ascending aortic replacement was performed with a Dacron graft. Pathological examination of the resected aortic wall revealed cystic medial degeneration. We report a rare case of ascending aortic aneurysm following surgical repair of the aortico-left ventricular tunnel and aortic valve replacement.

Adolescent↗

PubMed2005

Cognitive dysfunction following cardiovascular surgery.

OBJECTIVE: The aim of this study was the evaluation of perioperative cognitive dysfunction in patients undergoing cardiovascular surgery with or without cardiopulmonary bypass (CPB) and identification of the risk factors. SUBJECTS AND METHODS: Between July 2001 and October 2003, we performed cognitive examinations in 192 patients (mean age 65.5 +/- 7.6 years) who underwent elective cardiovascular surgery with or without CPB. The cognitive examinations (Hasegawa dementia scale) were done both pre- and postoperatively. Forty-six patients who had developed cognitive dysfunction postoperatively were included in Group A. The remaining 146 patients were placed in the control group (Group B). RESULTS: The patients in Group A were noted to be significantly older than those in Group B (69.8 +/- 7.4 vs. 64.1 +/- 7.2, p < 0.05). The number of patients who at risk for cerebrovascular disease was significantly higher in Group A than in Group B (p < 0.05). Among intraoperative variables, there were no significant differences between the two groups concerning the presence or absence of CPB, CPB duration, and operation duration. The length of postoperative hospitalization of the Group A patients was greater. Age was identified as the only predictor of postoperative cognitive dysfunction in multivariate analysis. CONCLUSION: In the present study, it is possible that CPB did not play a significant role in the genesis of cognitive dysfunction after cardiovascular surgery. Age appears to be the only significant predictor of postoperative cognitive dysfunction.

Age Factors↗

PubMed2005

Long-term evaluation of bovine pericardial bioprostheses in young women: influence of pregnancy.

OBJECTIVES: To avoid the fetal and maternal risks associated with anticoagulant therapy during pregnancy, the use of bioprostheses has been advocated for young women with cardiac valve disease during the childbearing years. Several reports have suggested the probability of pregnancy-related accelerated structural valve deterioration (SVD). The aim of this study was to assess the effect of pregnancy and delivery on bovine pericardial bioprostheses. METHODS: Between 1986 and 2004, 13 female patients received 14 bioprostheses. The women were segregated into two groups based on whether pregnancy occurred during follow-up: eight in the Pregnant Group (Group P) (including one case who underwent two operations), and six in the Nonpregnant Group (Group NP). RESULT: Early mortality was not observed. Late mortality was 12.5% for Group P and 16.7% for Group NP. There were a total of ten valve-related reoperations (seven in Group P and three in Group NP); the major reason was SVD in 64.3% of the cases. Freedom from valve-related reoperation at nine years was 28.6% in Group P and 33.3% in Group NP (p=0.338). Overall time from primary surgery to reoperation was 111 +/- 24.7 months, with no significant difference between the two groups (p=0.615). The Group P of eight patients had 12 pregnancies: ten deliveries and two abortions. There were no maternal or neonatal deaths. CONCLUSION: Pregnancy did not significantly influence the incidence of SVD and reoperation. The bioprostheses appears to provide female patients with more opportunity for uncomplicated pregnancies, deliveries and normal children than mechanical valves.

Adolescent↗

PubMed2005

Mitral stenosis after mitral valve repair using the duran flexible annuloplasty ring for degenerative mitral regurgitation.

The case is presented of a 47-year-old woman who had undergone mitral valve repair using the Duran annuloplasty ring four years earlier, and who was diagnosed with mitral stenosis owing to fibrous tissue overgrowth. In this patient, dense whitish fibrous tissue covered the annuloplasty ring and extended onto both leaflets of the mitral valve, narrowing its orifice and rendering the leaflets stiff and immobile. The pannus covering the mitral valve could not be stripped off without damaging the leaflets, making mitral valve replacement necessary. Mitral valve replacement with a St. Jude Medical mechanical heart valve prosthesis was successfully performed, and no major perioperative complications were encountered.

Female↗

PubMed2003

Total aortic arch grafting via median sternotomy using integrated antegrade cerebral perfusion.

BACKGROUND: In aortic arch grafting, antegrade cerebral perfusion prolongs the safe time of arch exclusion. However, there are the problems of cerebral embolism and distribution of the cerebral perfusion. We describe and analyze mortality and cerebral complications in patients undergoing total arch grafting using our refined technique. METHODS: Between June 1994 and March 2002, 100 consecutive patients underwent total arch grafting through median sternotomy. There were 49 atherosclerotic aneurysms and 51 aortic dissections. Fifty-four patients were operated on an emergency basis because of rupture or acute type A dissection. We conducted total arch grafting using hypothermic antegrade cerebral perfusion from every cervical vessel. Carbon dioxide gas was added to the cerebral perfusion in order to inhibit the increase in the cerebral vascular resistance during hypothermic cerebral perfusion. RESULTS: Hospital mortality was 4%. The causes of death were dysarrhythmia (n = 1), mesenteric necrosis (n = 1), and preoperative cardiac arrest (n = 2). On univariate analysis, preoperative shock and concomitant cardiac procedures were risk factors for hospital death. The rate of postoperative neurologic damage was 5%. Two patients suffered from cerebral infarction. Temporary neurologic dysfunction occurred in 3 patients. On univariate analysis, emergency surgery was a risk factor for postoperative neurologic damage. On multivariate analysis, there was no significant independent predictor of hospital mortality and neurologic damage. Actuarial survival at 96 months was 66.4 +/- 9.1%, and freedom from aortic accidents (reoperation, rupture, and cholesterol embolism) was 74.9 +/- 7.9%. CONCLUSIONS: The early- and long-term results of total arch grafting using integrated antegrade cerebral perfusion were found to be satisfactory.

Aged↗

PubMed2003

Sphingobium amiense sp. nov., a novel nonylphenol-degrading bacterium isolated from a river sediment.

A nonylphenol-degrading bacterial strain (YT(T)) was isolated previously from a river sediment sample obtained in Ami-machi, Ibaraki, Japan, and identified as a Sphingomonas species. In this study, the taxonomic relationship between strain YT(T), a recently described nonylphenol-degrading strain, Sphingomonas cloacae, and Sphingobium yanoikuyae, which is phylogenetically related, was examined. Their phenotypic characteristics were compared and levels of DNA-DNA relatedness between these strains were determined. Based on the results of physiological and biochemical tests and DNA-DNA hybridization, it is proposed that strain YT(T) (=IAM 15006(T)=JCM 11777(T)=CIP 107839(T)) represents a novel species of the genus Sphingobium, Sphingobium amiense sp. nov.

Alphaproteobacteria↗

PubMed2002

A case of fistula of the right common iliac aneurysm to the appendix.

We report a very rare case of spontaneous ilioappendicial fistula with right common iliac aneurysm. After the aneurysm was opened, afferent and efferent vessels were closed following extraanatomical femorofemoral bypass, and the appendectomy was performed. The wall of the aneurysm showed the atherosclerotic change and histologic study of the appendix confirmed the diagnosis of acute appendicitis. Enhanced computed tomography was useful for the diagnosis and the extraanatomical bypass was deemed the most effective operative strategy. The pathogenesis of the fistula was surmised to be related to the appendicitis.

Aged↗

PubMed2002

Total aortic arch grafting for acute type A dissection: analysis of residual false lumen.

BACKGROUND: In surgery for acute type A dissection, an unresected dissection and residual false lumina are causes of the progression of aneurysms and ruptures. We grafted the ascending aorta and total arch, the maximum grafting possible through a median sternotomy alone, in all patients with type A dissection extending to the descending aorta, wherever initial tears existed in the arch. METHODS: A total of 37 consecutive patients with acute type A dissection underwent ascending and total arch grafting between August 1994 and December 2000. Cerebral protection was achieved by selective cerebral perfusion. The distal anastomosis was conducted using the "Elephant Trunk" technique. Patent false lumina were evaluated using computed tomography 3 months after the operation. RESULTS: The hospital mortality was 8.1%. No major cerebral complications were observed. The incidence of residual thoracic patent false lumina was 26.5%. Univariate analyses showed Marfan syndrome and preoperative extension of false lumina to be statistically significant determinants of residual thoracic false lumina. On multivariate analysis, no other significant independent predictor of residual false lumina in the thoracic aorta was found. CONCLUSIONS: Outcomes of our strategy were satisfactory. However, residual thoracic false lumina could not be prevented in 26.5% of the patients. Thus, this extended operation is indicated in patients with initial tears in the aortic arch or distal arch, those with Marfan syndrome, and young patients with preoperative patent false lumina extending to the abdominal aorta.

Adult↗