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Biomedical subjects

T Isomura

Publications and source records attributed to T Isomura.

At least 109 records · Page 6Linked to original sources
PubMed1992

The internal thoracic artery and its branches after coronary artery anastomoses in pediatric patients.

The internal thoracic artery has been favored because of its superior early and late patency for coronary artery bypass grafting (CABG) in pediatric patients. We have studied the angiographic changes of the internal thoracic artery and its side branches before and after CABG with internal thoracic artery to the left anterior descending artery. The internal thoracic artery with remaining thymic or pericardial branches was patent but showed enlargement of the branches in the early period after the operation, and a postoperative exercise test suggested a remaining ischemic lesion in the bypass. Angiogram taken 1 year after CABG demonstrated the grown internal thoracic artery with disappearance of most of the side branches, which had been enlarged 1 month after the operation. Our findings suggest the importance of ligation of the whole proximal internal thoracic artery branches to maintain good early and late patency.

Child↗
PubMed1992

Augmentation of interleukin-2 production after cardiac operations in patients treated with erythropoietin.

It has been reported recently that cardiac operations can be followed by a transient impairment of cell-mediated immunity. In this study we examined indices of cell-mediated immunity in patients undergoing cardiac operations. Twenty-five of the patients received erythropoietin (200 U/kg) daily for 2 weeks before and after operation, and 30 matched control patients did not receive erythropoietin. On postoperative day 1, the numbers of total T cells and helper/inducer T cells were significantly higher in erythropoietin-treated patients than in control patients. The ability of patients' cells to make interleukin-2 in vitro increased after erythropoietin injection in the preoperative period. By postoperative day 1, erythropoietin-treated patients exhibited a fall in interleukin-2 production that was significantly less than that in control patients; levels increased by day 2 to a mean value twice that of the preoperative baseline and more than four times the corresponding mean level in the control groups, and levels returned to the baseline range by postoperative day 14. Levels of interleukin-2 production in erythropoietin-treated patients were significantly higher than those in control patients at each interval tested through postoperative day 7. These findings indicate that erythropoietin treatment not only augmented levels of circulating erythrocytes but also improved indices of cell-mediated immunity. Although the mechanism responsible for this effect remains to be determined, the finding suggests that erythropoietin might help to ameliorate or prevent the impairment of immune function that can occur after cardiac operations.

Cardiac Surgical Procedures↗
PubMed1992

Postoperative erythroderma after cardiac operations. The possible role of depressed cell-mediated immunity.

Erythroderma as a manifestation of graft-versus-host disease after cardiac operations with blood transfusion may occur more frequently in Japan than in other countries. We have seen this problem in five patients who, after heart operations, died with symptoms and signs characteristic of graft-versus-host disease: cutaneous eruption, fever, diarrhea, leukopenia associated with agranulocytosis, and liver dysfunction. In the three patients seen most recently, skin biopsy showed findings similar to those of graft-versus-host disease after bone marrow transplantation. In addition, immunologic investigation showed remarkable differences in the findings in these patients and in those who did not have a graft-versus-host disease-like syndrome after cardiac operations. In particular, interleukin-2 production in response to mitogen stimulation was markedly diminished after operation in our patients, and the ratio of OKT4+ cells to OKT8+ cells in peripheral blood was low, reflecting increased numbers of OKT8+ cells after the occurrence of symptoms. The results raise the possibility that transient depression of cellular immunity after cardiac operations with blood transfusion may contribute to the occurrence of postoperative acute graft-versus-host disease.

Aged↗
PubMed1992

[Coronary artery bypass grafting: does the use of arterial graft for coronary artery bypass grafting increase surgical risk?].

Since April in 1988 coronary artery bypass grafting (CABG) was performed in 177 patients and the clinical results were compared in SVG-group (n = 37) in which only saphenous vein graft (SVG) was used as a graft conduit and AG-group in which one arterial graft (AG-1 group, n = 92) or more than two arterial grafts were used (AG-2 group, n = 48). In SVG-group the age was older than that in AG-group, while coronary vessels were most involved in AG-2 group and the mean number of distal anastomosis increased more in AG-group. The total pump time and aortic cross clamping time showed no significant differences among the groups. Furthermore, the occurrence of perioperative myocardial infarction, requirement of intra-aortic balloon pumping, frequency of re-chest open for hemorrhage, or sternal infection showed no significant differences among the groups. Postoperative hospital deaths were in four (three cardiac deaths) of SVG-group and four (one cardiac and two graft-versus-host disease) of AG-group. These results suggest that the use of AG does not increase surgical risk and AG can be positively used for CABG.

Adolescent↗
PubMed1992

[Coronary artery bypass grafting in a patient with Kawasaki disease].

A 3-year-girl admitted because of angina at rest. She had been diagnosed as Kawasaki disease at the age of 3 months. At that time, a coronary aneurysm was detected by echocardiogram and aspirin had started to administer. At the age of 4 months, a cardiac arrest occurred after severe heart attack because of inferior myocardial infarction. At the age of 2 years and 6 months, she started to complain of a chest pain even at rest. Coronary angiography was performed, and it showed total occlusion of RCA and LAD. However, LAD was vaguely filled by collateral flow from diagonal branch, and 201Tl scintigraphy showed myocardial viability of anteroseptal area. At operation, the size of ITA was 1.2 mm in diameter. Coronary artery bypass grafting to LAD by ITA was performed. Three weeks postoperatively, graft patency was confirmed by coronary angiography. The girl discharged with good ability of exercise. The ITA seemed to be the first choice of conduit for CABG even in a small child, and to be useful for progressive surgical treatment of Kawasaki disease.

Child, Preschool↗
PubMed1992

[Advantage of internal thoracic artery for coronary arterial bypass surgery in patients over 70 years of age].

Between April 1988 and September 1991, 16 among 23 patients over 70 years of age underwent coronary bypass grafting (CABG) with at least one arterial graft. The age ranged from 70 to 77 years (mean, 72.1 years) and involved coronary lesions were two vessels in two patients and three vessels in 14 patients. Seven patients with unstable angina received emergency CABG. The number of distal anastomosis with arterial graft was mean of 1.3 per patient and left internal thoracic artery (ITA) was used as a pedicled graft in all patients. Sequential grafting with left ITA arterial graft was performed in two and right gastroepiploic artery was concomitantly used in three patients. No atherosclerosis was seen in left ITA, however, poor quality saphenous vein graft (SVG) was in five and atherosclerosis of ascending aorta was in five patients. After operation deep vein thrombosis of leg after harvesting SVG occurred in one patient. The angiogram performed within one month of operation in nine patients showed that the patency rate of arterial graft was 100% and that of SVG was 94.4%. The longest follow-up period was 42 months and New York Heart Association Functional Class improved to Class I or II in all patients. The use of pedicled ITA in elderly patient showed advantage for diseased ascending aorta and it seemed to prevent the postoperative complication due to the use of SVG.

Aged↗
PubMed1992

[The changes of the cell-mediated immunity in patients with administration of recombinant erythropoietin].

The change of cell-mediated immunity was studied in patients receiving open heart surgery with or without administration of recombinant erythropoietin (rEPO). Group I was not administered rEPO in 30 patients, and Group II was done intravenously with 200U/kg/day of rEPO for 6.4 +/- 2.4 days before operation and also for 7.2 +/- 3.6 days after operation in 20 patients. The ratio of reticulocyte increased in all patients receiving rEPO. In both groups the ratios of OKT3 and OKT4 positive T lymphocytes decreased significantly on postoperative day 1. However, the ratios in patients with rEPO increased more significantly than in those without rEPO. Lymphocyte blast formation which was indicated by PHA-SI (phytohemagglutinin stimulation index) increased after administration of rEPO. The postoperative PHA-SI in both groups showed similar changes. The level of interleukin-2 (IL-2) production increased after the administration similar to PHA-SI change. The level of it decreased on postoperative day 1 and increased on postoperative days 3 and 7. We administered 200U/kg/day of rEPO for 7 days in a patient with postoperative erythroderma after open heart surgery and the level of IL-2 production was found to also increase in patient according with recovery of symptom. In conclusion, our data suggested that the rEPO might effect on not only erythrocyte but also lymphocyte activation.

Adult↗
PubMed1992

Surgical treatment of ventricular tachycardia by balloon electric shock ablation. Potential effects on the mitral valve apparatus.

We have previously described a new surgical technique for control of arrhythmogenic foci in patients with recurrent ventricular tachycardia that we call balloon electric shock ablation. With this method sequential shocks are delivered to a grid of electrodes on a balloon that can be introduced across the mitral valve into the intact ventricle. A series of experiments was undertaken to investigate possible deleterious effects of balloon electric shock ablation when shocks are delivered directly to the mitral valve apparatus. In six animals shocks totaling 1200 joules were given through a closely spaced electrode grid applied to the area of the mitral valve. Nine to 12 weeks later, left ventricular and mitral valve function were assessed. Balloon electric shock ablation in the basilar portion of the ventricle was associated with decreased myocardial performance, as evidenced by ejection phase indices. In five of six animals balloon ablation led to minor thickening of the valve leaflets and chordal attachments plus necrosis of adjacent myocardium, including papillary muscles. In these animals there was no significant dysfunction of the valve observed. In the remaining animal, however, ablation was centered on the posterior papillary muscle and resulted not only in necrosis of the base of the papillary muscle but also in full-thickness scarring and thinning of the adjacent left ventricular wall. In this dog, mitral regurgitation was seen on long-term follow-up. We conclude that when balloon electric shock ablation is used to destroy a localized area of myocardium in the basilar portion of the intact ventricle, the procedure results in decreased myocardial performance. When shocks were directly applied to the mitral valve apparatus in five of six animals, ablation did not result in significant negative effects on the structure and function of the valve. In the sixth dog, however, shock delivery resulted in transmural necrosis and thinning at the site of papillary muscle insertion and was associated with severe mitral regurgitation with volume loading. Therefore caution should be used when considering clinical application of this technique if the area to be ablated is in the basal portion of the heart.

Animals↗
PubMed1992

[Study on reoperation in cardiac disease].

Between January in 1988 and September in 1990, 65 patients underwent reoperation for acquired heart disease. Previous operations were closed mitral commissurotomy in 19, open mitral commissurotomy in 19, mitral valve replacement in 22, aortic valve replacement in one, and mitral repair in 4. After median sternotomy performed by hand-operated chisel and hammer, minimized dissection of the adhesive lesion was achieved. During the sternotomy, two patients required additional right thoracotomy because of marked median sternal adhesion and major cardiovascular injury occurred in three patients. Cardioplegic solution was introduced in normograde fashion except in two patients. In two patients with previous MVR by porcine prosthesis severe calcification was found in the left atrial wall and the prosthesis was not removed in one. Postoperative complications were low cardiac output syndrome requiring intra-aortic balloon pumping in two, re-thoracotomy due to hemorrhage in one, and mild air embolism without neurological damage in two. There was one early death (1.5%) but no late death. Although perioperative complication seemed to increase in reoperation, post-reoperative results was as good as those in the primary cardiac operation and reoperation on cardiac surgery should be performed before losing the indication for operation.

Adult↗
PubMed1992

[Morphological and functional studies on implanted arterial graft].

Early morphological and functional changes in arterial graft were studied. Autologous free graft of dog femoral artery or vein was implanted in the arterial system and the changes of endothelial cell by scanning electron microscope and prostacyclin levels were observed. In arterial graft, endothelial cell detachment after the implantation was rarely observed except the site with mechanical damage around the anastomosis. The site of cell detachment regenerated by 21 days after the implantation. The prostacyclin level was 2.5 pg/mg in venous graft or 35.9 pg/mg in arterial graft. The level in venous graft decreased after the implantation and it increased according to the cell regeneration, while the level was stable in arterial graft. The prostacyclin level of internal thoracic artery or gastroepiploic artery in clinical use was 54.5 pg/mg or 50.1 pg/mg, respectively. However the level in saphenous vein (SV) was 17.3 pg/mg and there were significant differences between the levels of arterial grafts and one of SV. Conclusively the arterial graft was superior to venous graft in early morphological and functional changes after the implantation and the superiority in early period after graft implantation may be one of the factor to contribute good graft patency in long term period.

Animals↗
PubMed1991

Reoperation following total repair of congenital heart disease.

For the past 25 years we have performed 61 reoperations in 58 patients with congenital heart disease who previously underwent total correction for the diagnosed ventricular septal defect, tetralogy of Fallot, atrioventricular septal defect, atrial septal defect, total anomalous pulmonary venous connection (TAPVC), and other involvement for 27, 11, 5, 4, 4, and 7 patients, respectively. Causes of reoperation included 43 events of valvular lesion, 29 of residual septal defect, 5 of conduit failure, 5 of venous obstruction, 3 of hemolysis, 3 of infective endocarditis, and 2 of prosthetic valve dysfunction. Although 5 early and 4 late deaths were encountered, the remaining 49 patients (3 in New York Heart Association (NYHA) Class II and 46 in NYHA class I or II) survived the reoperation. The patients were followed up by echocardiography and chest X-ray examination, and reoperation was indicated under the following conditions: moderate to severe valvular insufficiency; residual defect causing the shunt ratio to be over 30% or a systolic pulmonary pressure over 50 mmHg; or a high pressure gradient over 50 mmHg across the right ventricular outflow tract. Early timing for reoperation seemed to be important in patients with pulmonary venous obstruction, prosthetic dysfunction, severe hemolysis and infective endocarditis.

Adolescent↗
PubMed1991

An evaluation of long-term results over 10 years after intracardiac repair of tetralogy of Fallot.

A follow-up study was conducted of 166 patients who had survived for more than 10 years after total correction of tetralogy of Fallot. The total number of patients in NYHA class I was 141 (85%); the other 25 patients had been medically treated or had followed a prudent life style. The factors which caused postoperative symptoms were residual lesions and ventricular arrhythmia. Ultrasonic echocardiography showed that among 72 patients with transannular patch, 68 (95%) showed moderate or severe pulmonary incompetence. There was a correlation of gamma = 0.43 between the severity of pulmonary incompetence and cardiothoracic ratio in the 48 patients without any residual lesions, while two cases with severe pulmonary incompetence showed obvious right ventricular failure. Ambulatory ECG monitoring was employed to study 53 patients. As a result, 21 patients were found to present solitary moderate or severe pulmonary incompetence, while premature ventricular contraction of Lown's grade 4A was seen in nine patients (42.9%). In conclusion, it is considered essential to carefully follow up patients after intracardiac repair of tetralogy of Fallot, especially those with severe pulmonary incompetence.

Adolescent↗
PubMed1991

[Percutaneous transluminal angioplasty of a constricting coronary artery bypass graft: a case report].

A case with percutaneous transluminal coronary angioplasty (PTCA) for the stenosis of saphenous vein bypass graft was reported. A 68-year-old woman developed repeated effort angina two months after emergency triple CABG. Coronary angiographic study revealed 90% stenotic lesion in a sequential vein graft which was located between proximal and distal OM. PTCA was successful to dilate the stenotic lesion from 90% to 25% narrowing. She has been free from angina after the CABG and PTCA.

Aged↗
PubMed1991

[Coronary artery bypass grafting combined with operation for non-cardiac disease].

During the last two years and six months, ten patients underwent operation for both coronary artery disease and non-cardiac surgery. There were six patients with vascular disease, three with gastric cancer and one with cholelithiasis. Six patients had simultaneous operation of both coronary artery bypass grafting (CABG) and non-cardiac surgery, and four underwent non-cardiac surgery mean of 105 days after CABG. The number of significant lesions of coronary artery in patients with simultaneous or two-staged operation was 2.2 +/- 0.8 or 2.8 +/- 0.5 per patient, respectively. The operative time in patients with simultaneous operation was 361 +/- 49 minutes. However, in patients with staged operation the time for cardiac surgery was 380 +/- 36 minutes and the time for non-cardiac operation was 388 +/- 83 minutes. There were no patients with complications after either cardiac or non-cardiac operation. In patients having surgical indications for both coronary artery and non-cardiac diseases, CABG should be performed prior to the non-cardiac surgery. In patients with normal cardiac function and sufficient operative time after CABG, concomitant operation seemed to be recommended. In case with advanced malignant disease or incompetent cardiac function, staged operation would be selected for good surgical result.

Aortic Aneurysm↗
PubMed1991

[Cardiovascular surgery in patients seventy years of age and older].

During 10 years between 1981 and 1990 surgical treatment was performed in 77 elderly patients (emergency 19) for cardiovascular disease at the 2nd Dept of Kurume Univ. Hospital. The 58 elective patients were studied. There were CABG in 29; valve replacement in 18; aneurysm operation in 11. The control patients were consisted of CABG in 60; valve replacement in 40; and aneurysm operation in 20 patients whose age were under 60 years. In the elderly group, operative mortality was 3 in 58 (5.2%) and there were no significant differences compared to that in the control patients. However, low output syndrome or respiratory complication was relatively prevented in the elderly patients and careful post operative management was required. The late results in the elderly patients NYHA or exercise tolerance was improved well. The 5 years actuarial survival rate was 93.3% in ischemic heart disease group, 87.7% in valvular heart disease group, and 90.0% in thoracic aneurysm group. No significant difference was seen compared to these results in control patients and no significant differences among these diseases.

Age Factors↗
PubMed1991

[A case report of atrial septal defect with quadricuspid pulmonary valve].

We reported the successful case of valvuloplasty on the quadriscuspid pulmonary valve which had pulmonary regurgitation. A 38-year-old woman was admitted with the complaint of palpitation. Atrial septal defect and pulmonary regurgitation were revealed preoperatively by the cardiac catheterization and doppler echocardiography. The malcoaptation of the pulmonary valve and pulmonary dilatation were diagnosed in echocardiography. At operation, the pulmonary valve was found quadricuspid and each cusp was same in size. The patient underwent the valvuloplasty on the abnormal cusps and the remarkable improvement of the coaptation was examined postoperatively. The patient had good clinical course for three years after operation.

Adult↗
PubMed1991

[Coronary artery bypass grafting for ischemic heart disease combined with aortitis].

Coronary artery bypass grafting (CABG) was performed in a 67-year-old woman with aortitis. She had a past history of right radical mastectomy. Preoperative coronary angiogram showed diffuse stenotic lesions in both right and left coronary arteries. The pressure gradient between ascending aorta and peripheral radial artery was 90 mmHg and the cause of coronary stenosis seemed to be hypertension due to stenotic distal aorta. The aortogram showed occluded bilateral internal thoracic arteries (ITA) and stenotic abdominal aorta. The cephalic artery was supplied by a large meandering artery via dilated gastroepiploic artery (GEA). And thus the GEA was not useful for CABG. Quadruple CABG was performed with mild varicose saphenous vein (saphenous vein grafts to left anterior descending artery and third branch, and sequential saphenous vein graft to right posterior descending and atrioventricular branches). It seemed to be important to demonstrate the arterial lesion of ITA and GEA before CABG in patients with aortitis.

Aged↗