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Biomedical subjects

A Seki

Publications and source records attributed to A Seki.

At least 19 recordsLinked to original sources
PubMed1996

A novel mutation in the mitochondrial tRNA(Thr) gene associated with a mitochondrial encephalomyopathy.

A novel G-to-A transition at nucleotide 15915 in mtDNA is described. The patient showed a combination of muscle weakness, hearing loss, mental retardation, and seizures. Muscle biopsy showed RRFs and focal COX deficiency. We sequenced all mtDNA, and found 5 novel nucleotide substitutions. Three of them were synonymous mutations, one was a missense mutation in cytochrome b gene (A-->G at nt 15422), and the last one was the 15915 mutation in tRNA(Thr) gene. We screened for the 15422 and the 15915 mutations with mismatch primers and found that one of 104 normal individuals carried the former one and none of 175 had the latter one. The 15422 mutation existed in homoplasmic states both in the patient and the normal individual, suggesting that this is a polymorphism. In contrast the 15915 mutation resided in heteroplasmic states in muscle, skin fibroblast and blood. The nucleotide substitution at nt 15915 disrupts a highly conserved base pair in anticodon stem of the tRNA(Thr). Our data suggest that the 15915 mutation is an additional mtDNA mutation responsible for mitochondrial encephalomyopathies.

Adolescent↗
PubMed1996

Intravascular imaging of serial changes of disease in saphenous vein grafts after coronary artery bypass grafting.

To clarify the structural changes of saphenous vein grafts after coronary artery bypass grafting, intravascular ultrasound and angioscopic images were obtained from 23 grafts in vivo and 5 grafts and 3 new veins in vitro; the images were compared with histologic findings. Intravascular ultrasound demonstrated a single-layered appearance at new veins and all of the angiographically normal grafts within 6 months after surgery. A triple-layered appearance that might be related to the remarkably proliferative and degenerated intima was revealed histologically at 73.3% of the normal sites of grafts between 5 and 10 years after operation. In 83.3% of the stenoses at several years after operation, angioscopy showed yellow atheromatous plaques, often with a friable surface; a heterogeneous, lucent echo pattern was revealed on intravascular ultrasound. Thus intravascular ultrasound and angioscopy may be used to identify the morphologic changes of graft at different points after implantation more precisely than conventional angiography.

Angioscopy↗
PubMed1996

Causes of coronary events after successful coronary angioplasty.

OBJECTIVE: To determine the causes and incidence of coronary events after successful coronary angioplasty. METHODS: We evaluated retrospectively follow-up angiograms of 60 patients with coronary events (27 with myocardial infarction, 33 with new-onset angina pectoris) from among 930 consecutive patients who underwent successful elective angioplasty between February 1985 and April 1994. Patients who had undergone percutaneous transluminal coronary angioplasty to bypass grafts were excluded. RESULTS: No fatal cardiac events occurred within 6 months of percutaneous transluminal angioplasty; 10 occurred thereafter. Fifteen patients who developed early (3.9 +/- 1.8 months) restenosis showed non-Q-wave infarction resulting from severe restenosis at the previously dilated site. In patients without early restenosis, cardiac events developed not from the previously dilated site, but from previously undilated, non-obstructive sites. Furthermore, it was found that the patency of the previously dilated site remained good for a long period of time (41 +/- 23 months) in 96% (43 of 45) of these patients. These findings indicate that the vast majority of cardiac events in patients without early restenosis resulted from new lesions distant from the previous angioplasty site. CONCLUSIONS: Fatal cardiac events resulting from early restenosis were rare. In patients with no evidence of restenosis, long-term patency remained good. However, a proportion of these patients developed cardiac events resulting from lesions distant from the previous angioplasty site and hence careful long-term follow-up is essential.

Adult↗
PubMed1996

Long-term outcome in single-vessel coronary artery disease in Japanese patients.

We assessed the long-term outcome of medical therapy in 453 patients who underwent coronary angiography in the period from September 1973 to February 1984, and who had a significant stenotic lesion (75% or more stenosis) in a single coronary artery. The mean follow-up period was 9.8 years. The 5- and 10-year survival rates were, respectively, 96.0% and 91.3% in these patients, and these survival rates were comparable to the cumulative survival rates in the age-matched healthy male controls determined on the basis of overall death. Cardiac death occurred in 35/453 patients (7.7%) with single-vessel disease (SVD), and non-fatal myocardial infarction occurred in 17 patients (3.8%) during the follow-up period. The incidence of cardiac events, which was defined as cardiac death and nonfatal myocardial infarction, was as low as 1.2% per year. The survival rates were compared in terms of the presence or absence of myocardial infarction, the type of the coronary artery with stenosis, and proximal versus distal location of the stenotic lesion in the left anterior descending artery (LAD). The survival rates were similarly high in both assessed groups, with no significant differences. Patients with SVD treated medically had a good prognosis, except for those patients with decreased left ventricular function (ejection fraction < or = 40%). These factors should be taken into consideration when selecting therapies for patients with SVD.

Case-Control Studies↗
PubMed1996

[Valve replacement concomitant with anulus reconstruction].

It is important that surgical treatment of infective endocarditis involves complete debridement of the affected tissue. In case of abscess formation in the mitral anulus and/or aortic root, disruption of the anulus occurs because of radical resection of the abscess. David et al. reported a new technique for mitral and aortic anulus reconstruction. The novel part of the technique was the endocardial repair, i.e., suturing of a pericardial patch to the endocardium of the left ventricle. We were surprised to learn that the left ventricular endocardium and muscle are capable of tolerating the stress induced by the prosthetic ring, especially in the mitral position. Since 1992, we treated eight cases of anulus disruption using this technique ; 5 cases involved the mitral anulus, 1 involved the aortic, and 2 involved both. We used a slightly different technique involving suturing of a patch not only to the left ventricular endocardium but also to left atrial wall for reinforcement. Two patients died in the perioperative period. One had a brain abscess ; the other had methicillin-resistant Staphylococcus aureus sepsis and mediastinitis. There was 1 late (sudden, unknown) death 3 years after the operation. No perivalvular leakage, dehiscence of the patch, hemolysis, prosthetic valve endocarditis, or thromboembolism have been observed in the other 5 patients.

Abscess↗
PubMed1996

[Long-term recovery of regional wall motion in patients with medically treated anterior myocardial infarction: quantitative assessment of the post-infarction left ventriculograms].

The effect of medical treatment without reperfusion therapy on the long-term recovery of regional wall motion was evaluated retrospectively in 28 patients with transmural acute anterior myocardial infarction who had coronary angiography and left ventriculography at 1-6 months after the onset of the episode and were followed for a mean of 65 months. In all patients, initial coronary angiography revealed significant stenosis in only the left anterior descending artery (LAD). All patients were treated medically without reperfusion therapy (such as thrombolytic therapy, angioplasty, or bypass grafting). The regional wall motion in the LAD territory was measured by the centerline method using the right anterior oblique projection. Long-term improvement in anterior wall motion is unlikely in patients with patent LAD or underdeveloped collaterals to the LAD (38%). However, subsequent anterior wall motion frequently improved among patients with severely stenotic or occluded LAD (63%) and well-developed collaterals (73%). Therefore, the anterior wall motion of some LAD-related infarctions improves spontaneously, the extent of coronary collaterals is an important determinant of long-term improvement, and the improvement in wall motion is completed within the early period of acute anterior infarction in patients with patent LAD.

Angiocardiography↗
PubMed1996

[Quadricuspid aortic valve: report of a case associated with severe aortic regurgitation].

A case of quadricuspid aortic valve is reported. A 53-year-old man was admitted to our hospital for exertional dyspnea. He had a grade 3/6 to & fro murmur along the left sternal border. Aortogram showed grade 3 aortic regurgitation. The aortic valve consisted of two equal larger cusps and two equal smaller cusps, and a supernumerary cusp located between the right and noncoronary cusps. Aortic valve replacement was performed successfully and his post operative course was uneventful. On histological examination, the resected cusps showed fibrotic thickening and no sign of previous inflammatory disease. Quadricuspid aortic valve has been extremely rare. 27 Japanese cases of quadricuspid aortic valve which were corrected surgically are reviewed.

Aortic Valve↗
PubMed1996

[A case report of right-sided cardiac and pulmonary thromboembolism treated by emergent operation].

A forty-four-year-old man with a clinical diagnosis of diabetes melitus and severe obesity (height 170 cm, weight 108 kg) was admitted to the hospital on 12th January 1995 because of acute myocardial infarction, and on 21st January, he was referred to our hospital with sudden onset of shock, bradycardia, loss of consciousness in spite of having recovered well from myocardial infarction. The echocardiography and pulmonary arteriography revealed a pulmonary embolism and a tumor in the right atrium. Administration of tissue plasminogen activator (TPA) was not sufficiently effective. An emergency operation (pulmonary arteriotomy, right atriotomy, milking of bilateral lungs) with cardiopulmonary bypass revealed a massive consecutive thrombus, which occupied the right atrium, right ventricle and bilateral pulmonary artery. The postoperative course was uneventful.

Adult↗
PubMed1996

[Successful coronary angioplasty in a patient with acute myocardial infarction caused by prosthetic valve endocarditis].

A 65-year-old man was hospitalized with persistent fever (up to 39 degrees C) of 3 weeks' duration 9 years after aortic valve replacement with a Hall-Kaster prosthesis. Multiple blood cultures demonstrated beta-Streptococcus. Transesophageal echocardiography disclosed mobile vegetations at the prosthetic valve with normal valve function. A diagnosis of late prosthetic valve endocarditis was made. Therapy was begun with penicillin G, cefazolin, and gentamycin. On the 20th hospital day, he suddenly developed severe chest pain. Electrocardiography was consistent with acute extensive anterior myocardial infarction. Coronary angiography revealed that the left anterior descending coronary artery was occluded in its proximal portion with an intraluminal filling defect, which was morphologically the same as the vegetation that had been demonstrated previously. Percutaneous transluminal coronary angioplasty was performed, and coronary artery perfusion was restored 4.5 hours after the onset of chest pain. Transesophageal echocardiography performed 2 days later revealed that the vegetation at the prosthetic valve level had nearly disappeared. This is the first reported case of coronary angioplasty in a patient with acute myocardial infarction caused by prosthetic valve endocarditis in Japan.

Aged↗
PubMed1995

Comparison of long-term efficacy of medical treatment versus percutaneous transluminal coronary angioplasty (PTCA) in single-vessel disease.

The long-term outcome of PTCA and medical therapy were compared in patients with SVD. All patients were confirmed to have > or - 75% stenosis of a major coronary artery by coronary arteriogram. The 5-year survival rates were 96.0% for medical therapy and 98.9% for successful angioplasty. Both therapies achieved an equally good long-term outcome for SVD. The incidence of nonfatal cardiac events during follow-up was higher in patients treated by PTCA than in those on medical therapy, but there was no difference between the two groups in the incidence of nonfatal MI at 5 years (2.5% vs 1.8%). The most common cardiac event in patients undergoing successful PTCA was repeat intervention associated with restenosis. In view of the long-term efficacy of PTCA, the high restenosis rate remains an important problem and it is necessary to elucidate the causes of restenosis and develop countermeasures as soon as possible.

Adult↗
PubMed1995

Comparison of long-term efficacy of medical treatment versus coronary artery bypass grafting (CABG) in multivessel coronary artery disease.

The long-term results of medical therapy and coronary artery bypass grafting (CABG) were compared in patients with multivessel disease. All patients were confirmed to have > or = 75% luminal narrowing of major coronary arteries by coronary arteriogram. When multivessel disease was stratified into double- and triple- vessel disease, the outcomes varied. In triple-vessel disease, the outcome with CABG was good, but the outcome was unfavorable in those employing medical therapy, particularly in patients with decreased left ventricular (LV) function. In patients with double-vessel disease with good LV function, the long-term results with medical therapy were just as favorable as those with CABG. However, double-vessel disease complicated by reduced LV function (ejection faction < or = 40%) had a clearly less favorable outcome when treated with medical therapy than with CABG. Thus, it is important for patients with multivessel disease to undergo revascularization if indicated, to improve their prognosis. On the other hand, the incidence of cardiac events arising from vein graft occlusions tended to increase in CABG patients after 5 years or more following surgery.

Aged↗
PubMed1995

[A case report of primary pulmonary artery sarcoma].

A 49-year-old man was admitted because of dyspnea and generalized edema. CT scan pulmonary scintigram and cardiac catheter examination revealed pulmonary arterial obstruction due to a tumor associated with right heart failure. The tumor was extirpated as much as possible by a pulmonary arteriotomy under cardiopulmonary bypass. Postoperatively, right ventricular pressure decreased to about 40 mmHg while PO2 increased to the normal level. Histological examination of the tumor revealed rhabdomyosarcoma arising from the pulmonary artery. Chemotherapy consisting of a single course of CDDP and adriamycin was administered.

Humans↗
PubMed1995

[A case report of traumatic diaphragmatic hernia treated by thoracoscopic surgery].

A 56-year-old man who had been accidentally hit on the right side of the chest about 20 days previously was admitted because of intractable cough. Chest X-ray and CT scan revealed a right-sided diaphragmatic hernia and slight pneumothorax. No other hemorrhagic or perforative complications were detected. On the third hospital day, the patient underwent therapeutic thoracoscopy. Herniated transverse colon and liver were repaired through the abdominal cavity and the lacerated diaphragm was sutured through four thoracoports with video system assistance. The postoperative course was uneventful, and the patient was discharged 28 days later.

Endoscopy↗
PubMed1995

[Two cases of traumatic aneurysm of the aortic isthmus].

Two cases with blunt traumatic aneurysm of the aortic isthmus were treated recently. One was operated in early stage using heparin-bounded transient aorto-aorta bypass. The other underwent delayed operation with aorto-aorta bypass using centrifugal pump. Patch closures with Dacron fabric sealed by equine pericardium were performed in both of them with satisfactory results. We discussed the controversial problems, the timing of the operation and the method of adjunct circulation.

Adult↗
PubMed1995

Prevention of restenosis by bezafibrate after successful coronary angioplasty.

BACKGROUND: To study the role of bezafibrate in prevention of restenosis after successful percutaneous transluminal coronary angioplasty (PTCA), we evaluated the incidence of restenosis and its correlation with serum lipid levels and effects on the coagulation-fibrinolytic system. METHODS: Subjects who had undergone successful elective PTCA were classified into three groups based on their triglyceride level and whether or not bezafibrate was administered. Fifty-two patients who had a triglyceride level < 150 mg/dl were classified as group A. Those with a triglyceride level +/- 150 mg/dl were randomly and prospectively allocated to receive either bezafibrate (group B, n = 21), or no lipid-lowering treatment (group C, n = 22). The restenosis rates in all three groups were subsequently monitored and correlated with serum levels of lipids and coagulation-fibrinolytic system markers. RESULTS: In the bezafibrate group, three of 21 patients (14%) had restenosis compared with 12 of 22 (55%) in group C and 18 of 52 (35%) in group A. In groups A and C, fibrinogen and triglyceride levels were significantly higher in the patients with restenosis. At the time of re-evaluation, serum triglyceride, fibrinogen, and plasminogen activator inhibitor type 1 (PAI-1) levels were lower and high-density lipoprotein (HDL) cholesterol levels were higher in the bezafibrate group than in group C. By logistic regression analysis, triglyceride and PAI-1 were found to be significant risk factors for postangioplasty restenosis. CONCLUSIONS: Triglyceride is a risk factor for post-PTCA restenosis, and bezafibrate reduces the post-PTCA restenosis rate in patients with a high triglyceride level. In the bezafibrate group, a significant decrease in PAI-1 was observed in association with a decrease in triglyceride level and an elevation of HDL cholesterol level. This suggests that improvement in fibrinolytic capacity is involved in the mechanism of decrease in the rate of restenosis.

Angioplasty, Balloon, Coronary↗
PubMed1994

The effects of using a leukocyte removal filter during cold blood cardioplegia.

During myocardial ischemia, neutrophils and platelets exert negative effects on the myocardium. In this study, we used a leukocyte removal filter during cardioplegia, and investigated its effect on myocardial damage during reperfusion by measuring the plasma levels of granulocyte components, platelet components, and cardiac enzymes [creatinine phosphokinase (CK) and creatinine phosphokinase myocardial band (CK-MB)] in 24 patients who underwent cardiopulmonary bypass. The patients were divided into two groups of 12 according to whether or not a filter was placed in the cardioplegic route. Blood samples were drawn directly from the coronary sinus before aortic cross clamping, and at 1, 5, and 15 min after declamping. Group F, which had the filter, showed better cardiac enzyme and lipid peroxidation results than group N, which did not. The results of this study suggest that the application of a filter during cold blood cardioplegia may reduce myocardial damage.

6-Ketoprostaglandin F1 alpha↗