Biomedical subjects

K Yagyu

Publications and source records attributed to K Yagyu.

At least 37 records · Page 2Linked to original sources

PubMed1998

[Coronary artery fistula with left atrial myxoma: report of a case].

A 64-year-old male was referred for surgical treatment of left atrial myxoma. Preoperative coronary angiography revealed coronary artery fistula from the left anterior descending artery and the circumflex artery draining into the main pulmonary artery. Operative treatment was performed including resection of the myxoma, patch closure of the atrial septal defect, and closure of the fistula with pledgeted mattress sutures from within the main pulmonary artery on cardiopulmonary bypass. His postoperative course was uneventful, and disappearance of the left atrial myxoma and the coronary artery fistula was ascertained by echocardiography and coronary angiography.

Arterio-Arterial Fistula↗

PubMed1997

The stiffness of lymph nodes containing lung carcinoma metastases: a new diagnostic parameter measured by a tactile sensor.

BACKGROUND: It is believed that the stiffness or hardness of a lymph node containing a metastasis differs from that of lymph node without a metastasis because of the difference in tissue density, which is derived from the lymph node's histopathologic features. Prior to this study, however, there had been no attempts to quantify the hardness or stiffness of lymph nodes. The authors developed a new tactile sensor and system for measuring the stiffness (g/cm) of lymph nodes accurately, and they studied its utility as a tool for diagnosing lymph node metastases. METHODS: Clinical specimens were obtained from 14 patients who underwent lobectomy or pneumonectomy with hilar and mediastinal lymph node dissection for nonsmall cell lung carcinoma at the University of Tokyo between January and July 1996. With the tactile sensor developed by the authors, 212 resected lymph nodes were measured for their stiffness. RESULTS: Among these 212 resected lymph nodes, 57 were diagnosed as containing metastases (38 from adenocarcinomas and 19 from squamous cell carcinomas). The mean stiffness of the lymph nodes that contained metastases was 3.35 +/- 1.57 g/cm, and that of lymph nodes without metastases was 1.23 +/- 0.50 g/cm (P < 0.001). Receiver operating characteristic analysis revealed that the area under the curve was 0.93, indicating excellent accuracy of the method. When the cutoff was 1.5 g/cm, the sensitivity was 91.2% and the specificity was 78.1% for detection of lymph node metastases. CONCLUSIONS: Measurement of the stiffness of resected lymph nodes was confirmed as an accurate approach to diagnosing lymph node metastases without knowledge of other factors, such as lymph node size or color.

Aged↗

PubMed1997

Hemoptysis from an emphysematous bulla developing after open-heart surgery: report of a case.

We present herein the case of a 62-year-old woman with an emphysematous bulla who developed intractable hemoptysis 16 days after undergoing mitral and aortic valve replacement with tricuspid annuloplasty. A bronchoscopic examination with balloon occlusion of the bronchial lumen revealed that the blood source was the right middle lobe bronchus. A computed tomographic (CT) scan of the chest subsequently demonstrated a blood-filled emphysematous bulla in the right middle lobe. A right middle lobectomy was performed and the bulla was observed to be swollen with clotted blood. The respiratory tract bleeding stopped immediately after the lobectomy. Pathohistological examinations suggested that disruption of the pulmonary vessels in the wall of the bulla had caused the respiratory tract bleeding.

Aortic Valve Insufficiency↗

PubMed1997

Four-channeled aortic dissection and rupture.

A four-channeled aortic dissection is quite rare, which is a highly life-threatening situation predisposing to aortic rupture. We report a successful management of a four-channeled aortic dissection and an aortic rupture in a 59-year-old woman with Marfan's syndrome 11 years after an initial Bentall procedure for DeBakey type I dissection. The total arch and the descending thoracic aorta were replaced under deep hypothermia and circulatory arrest.

Adult↗

PubMed1997

Structural changes of immunoglobulin G oligosaccharides with age in healthy human serum.

Age-related changes of IgG N-linked oligosaccharides isolated from normal human serum are reported for 403 individuals (male 227 and female 176), varying in age from 0 to 85 years. The IgG N-linked oligosaccharides were released from the protein by digestion with a glycoamidase and reductively aminated with the fluorescent reagent, 2-aminopyridine. The mixture of pyridylaminated oligosaccharides was separated at high resolution by HPLC using a reverse-phase column. From the results of neutral oligosaccharide analysis, agalactosyl glycoform and bisecting GlcNAc-containing glycoform were shown to increase with increasing age. Spearman's correlation coefficients were 0.503 and 0.473, respectively. Thus, in healthy people, an increase of both types of glycoforms correlates weakly with age. In addition, differences were demonstrated between male and female groups in their twenties. The quantity of agalactosyl glycoform was found to be lower in females than in males. No significant differences, however, were observed in the quantity of bisecting GlcNAc-containing glycoforms between males and females.

Adolescent↗

PubMed1997

Fibrous tissue overgrowth and prosthetic valve endocarditis: report of a case.

Mechanical valve stenosis without restricted occluder motion and paravaluvular leakage developed in a patient who had undergone patch closure of partial atrioventricular septal defect and replacement of the left atrioventricular valve 13 years previously. Dense calcification of the supravalvular region was shown in a cineradiogram, whereas transthoracic and transesophageal echocardiography failed to reveal any obstructive mechanism. Elevated transprosthetic pressure gradient with unrestricted occluder motion suggested prosthetic valve stenosis resulting from fibrous tissue overgrowth, although this was not visualized by the modern diagnostic imaging tools. Reoperation confirmed calcified fibrous tissue overgrowth obstructing the mechanical valve inflow. Examination of resected tissue revealed prosthetic valve endocarditis due to alpha-streptococcus. Paravalvular leakage accompanying fibrous tissue overgrowth may indicate the presence of prosthetic valve infection even if the clinical manifestations are scarce.

Calcinosis↗

PubMed1997

Mitral valve repair through combined left atrial and ventricular approach for congenital mitral stenosis.

A 3-year-old boy underwent mitral valve repair for congenital mitral stenosis through combined superior-septal atriotomy and apical left ventriculotomy. The operation was performed safely with excellent exposure of the subvalvular apparatus by the ventricular approach, while sufficient visualization of the valvular lesion was obtained by the atrial approach. Postoperative echocardiography demonstrated normal left-ventricular motion and no residual mitral stenosis.

Cardiac Surgical Procedures↗

PubMed1997

Mitral valve repair with extensive resection of the anterior leaflet for regurgitation due to Barlow's disease. Report of a case.

We recently performed mitral valve repair for a case of mitral regurgitation due to Barlow's disease, which is relatively rare in Japan. Both the anterior and posterior leaflets were affected by advanced myxomatous change, and appeared markedly thickened and redundant. Although extensive resection of the anterior leaflet is not a generally accepted method, nearly one fourth of the anterior leaflet was resected in this case. Now, at 36 months after the operation, there is only trivial regurgitation and the patient is doing well and without symptoms. We believe that extensive resection of the anterior leaflet can be a useful treatment for repair of a redundant anterior leaflet with excess tissue.

Cardiac Surgical Procedures↗

PubMed1997

Relationship between serum carotenoid levels and cancer death rates in the residents, living in a rural area of Hokkaido, Japan.

The relationship between serum carotenoid levels and cancer death in rural Japanese residents, aged more than 39 years, was examined epidemiologically. The follow-up subjects participated in the comprehensive health examinations, every August from 1986 to 1989, were 929 males and 1424 females, living in a rural area of Hokkaido, Japan. During 2-8 years to December 1994, the ninety-eight deaths were observed among the cohort; that is, deaths from all causes were 67 males and 31 females, and cancer deaths were 34 males and 10 females. Serum samples at fasting were collected at the entry of the cohort and serum levels of beta-carotene, alpha-carotene and lycopene were measured by the HPLC method. The relation between the mortality rates and serum carotenoid levels was estimated statistically using the Cox's proportional hazard model. The results were as follows; the hazard ratio with the overall on high serum beta-carotene levels to those of lower was 0.46 (95% C.I.: 0.27-0.78) for all causes and 0.33 (95% C.I.: 0.14-0.75) for cancer deaths. This result suggested that high levels of serum beta-carotene may play some roles on preventing cancer death.

Adult↗

PubMed1997

Thoracoscopic implantation of a pacemaker lead: experimental study.

We have performed five thoracoscopic pacemaker lead implantations into the porcine myocardium. A small opening, approximately 2 cm in diameter, was made thoracoscopically in the pericardium overlying the apex of the left ventricle, avoiding phrenic nerve injury. Three screw-in type or two stab-in type standard sutureless unipolar epicardial electrodes were introduced through a trocar, and then screwed or stabbed into the myocardium near the apex of the left ventricle, avoiding the coronary vessels. Hemorrhage and arrhythmia were negligible during the procedures. Electrical tests of the pacing threshold and lead impedance after implantation of the leads revealed acceptable values in each lead. We conclude that thoracoscopic implantation of pacemaker leads is feasible, and may be used as a minimally invasive option when conventional transvenous techniques are unavailable or contraindicated.

Animals↗

PubMed1997

[A patient with mitral stenosis due to infective endocarditis].

A 51-year-old woman presented with mild stenosis of the mitral valve which had become thickened and rigid due to infective endocarditis, manifesting as persistent fever of up to 40 degrees C and general fatigue of a few days' duration. A harsh systolic murmur was heard. Multiple blood cultures revealed alpha-streptococcus. Echocardiography disclosed asymmetric septal hypertrophy (interventricular septal thickness/posterior wall thickness, 19/14 mm) and systolic anterior wall motion of the mitral valve. Continuous wave Doppler ultrasonography showed a peak left ventricular outflow tract pressure gradient of 170 mmHg. Transesophageal echocardiography revealed vegetations on the anterior mitral leaflet, aortic valve and interventricular septum along the left ventricular outflow tract. In particular, the anterior mitral leaflet was thickened and moved poorly. The calculated mitral valve areas was 1.5 cm2 and peak diastolic left atrium-left ventricle pressure gradient was 7 mmHg. A specimen of the mitral valve did not reveal commissural adhesion, but the anterior mitral leaflet showed marked fibrous thickening caused by scarred vegetation. Based on these findings, the diagnosis was hypertrophic obstructive cardiomyopathy complicated by infective endocarditis and "mitral stenosis". Valvular regurgitation is a common complication of active and healed infective endocarditis. In contrast, infective endocarditis rarely causes valvular stenosis except for stenosis caused by large fungus vegetation.

Cardiomyopathy, Hypertrophic↗

PubMed1997

[Improvement of cardiac function by aortic valve replacement for chronic aortic regurgitation with carbomedics heart valve].

Cardiac function after aortic valve replacement for chronic aortic regurgitation with CarboMedics heart valve was evaluated repeatedly by echocardiography and some examinations in 27 cases. There was no late death and all patients belonged to NYHA I functional class postoperatively. Systolic and diastolic dimensions of left ventricle, left ventricular mass index, cardiothoracic ratio and SV1+RV5 on electrocardiography improved significantly within half a year and those improved results remained thereafter. Fractional shortening of left ventricle also improved gradually and the difference reached statistical significance one year later. This investigation revealed reduced systolic function or eccentric myocardial hypertrophy were often reversible. Average values of systolic diameter and fractional shortening late after operation were within normal range even in cases whose preoperative systolic function were severely depressed. Left ventricular mass index decreased markedly although postoperative values were still out of normal range in most cases. These results suggest that aortic valve replacement can be indicated even in cases of aortic regurgitation with severely impaired preoperative cardiac function.

Adolescent↗

PubMed1997

[Reoperation for relief of valvular and supravalvular stenosis late after aortic valve replacement with Manouguian's anulus enlargement: report of a case].

Thirteen year-old boy who received aortic valve replacement with Manouguian's anulus enlargement for congenital aortic stenosis 7 years ago developed valvular and supravalvular stenosis. Pressure gradient between left ventricle and aorta was 55 mmHg. The etiology of supravalvular stenosis was extensive patch plasty of ascending aorta and severe degeneration of expanded polytetrafluoroethylene patch. Moreover, white hard mass existed just outside the patch and was one of the components of the stenosis. This mass was acellular calcification without foreign body reaction. Degenerated prosthetic patch was thoroughly resected, and redo Manouguian's procedure with autogeneous pericardium was performed. We tried to use two sizes larger 21 mm valve, but, after all, 19 mm valve was sewn into place. His postoperative course was uneventful.

Adolescent↗

PubMed1997

[Reoperation for mitral regurgitation 13 years after aortic valve replacement and manouguian's anulus enlargement: report of a case].

The patient was 22-year-old female. She had undergone aortic valve replacement and Manouguian's anulus enlargement with low porosity woven Dacron patch for congenital aortic stenosis 13 years ago, and developed mitral regurgitation 9 years after that operation. Two regurgitant flow were observed. One was originated from the orifice due to mitral prolapse. The other was from a tear in the anterior leaflet. It was around the tip of the prosthetic patch, approximately 7 mm in size, and was repaired easily. But the mitral valve itself was found to be malformed and prolapsed, requiring mitral valve replacement. Her postoperative course was uneventful.

Adult↗

PubMed1996

Successful management of massive pulmonary tumor embolism from renal cell carcinoma.

Renal cell carcinoma occasionally invades the inferior vena cava and rarely extends to the right atrium. However, despite the frequency of venous extension, it is unusual to recognize patients with massive pulmonary tumor embolus clinically. We describe a 60-year-old man who underwent pulmonary tumor embolectomy using cardiopulmonary bypass combined with profound hypothermia and intermittent low-flow perfusion. The patient is currently alive and well without implantation metastasis 6 months after the operation.

Carcinoma, Renal Cell↗

PubMed1996

Mitral valve replacement after percutaneous transvenous mitral commissurotomy.

Percutaneous transvenous mitral commissurotomy is widely performed as the first choice of the non-pharmacological treatments for mitral stenosis. Five patients have been identified who required mitral valve replacement after percutaneous transvenous mitral commissurotomy. The causes leading to mitral valve replacement were mitral regurgitation in three cases and insufficient commissurotomy in two. Massive mitral regurgitation is one of the most serious complications of percutaneous transvenous mitral commissurotomy. This report aims to elucidate the mechanism of massive mitral regurgitation occurring during percutaneous transvenous mitral commissurotomy. In every such case, there was a large tear in the posterior leaflet without any split in the commissures. The Japanese literature reports that 16 patients have undergone mitral valve replacement for massive regurgitation after percutaneous transvenous mitral commissurotomy: 14 of these cases had a tear in one of the leaflets and no evidence of splitting of the posterior commissure. These facts indicate that relative fragility of the leaflets as compared with rigidity of commissural fusion, especially in the posterior commissure, is an important factor of massive mitral regurgitation during percutaneous transvenous mitral commissurotomy.

Aged↗

PubMed1996

Open-heart surgery in Jehovah's Witness patients.

Open-heart surgery has been performed since 1975 on 25 patients who are Jehovah's Witnesses by religion. The patients' ages ranged from 6-60 years, and their body weights from 18-51 kg. Surgical procedures included correction of congenital heart disease in 14 patients and valve repair or replacement in 11. Six procedures were reoperations. The lowest mean haematocrits, during perfusion and the postoperative period, were 22.7% (range 15.0-31.0%) and 27% (range 16.0-36.0%), respectively. Twenty-four patients survived and are alive and well. One patient died of low output failure before discharge. The blood return system reduced blood loss. Five of the patients who underwent cardiac surgery received recombinant erythropoietin before and after surgery, leading to higher postoperative haematocrits. In one patient, a haematocrit which fell to 16.9% after surgery was raised to 27% by administration of erythropoietin, without blood transfusion. In two recent cases, high doses of aprotinin were used during surgery, resulting in better haemostasis after cardiopulmonary bypass.

Adolescent↗

PubMed1996

Tuberculous pseudoaneurysm of the thoracic aorta.

Tuberculous pseudoaneurysm has been reported to be a fatal, but rare complication of tuberculosis. We report a case of a 68-year-old man who underwent successful surgical treatment for a tuberculous pseudoaneurysm of the thoracic aorta with bronchial communication, and review previous reports of patients who also underwent operation for similar lesions, focusing especially on the pathway of infection to the aorta.

Aged↗