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Biomedical subjects

K Kosuga

Publications and source records attributed to K Kosuga.

At least 19 recordsLinked to original sources
PubMed1992

Partial brachiocephalic perfusion under hypothermic cardiopulmonary bypass. An experimental study.

We studied electrophysiological, oxygen metabolic, and histological variables in dogs to establish the reliability and safety of partial brachiocephalic perfusion (PBP) under hypothermic cardiopulmonary bypass (CPB) at 23 degrees-25 degrees C. Sixteen mongrel dogs were divided into two groups. Six (control group) underwent typical hypothermic CPB for 90 min, and 10 (PBP group) underwent PBP under hypothermic CPB for 90 min. During core cooling on the CPB, a progressive reduction in voltage and slowing of frequency of the electroencephalogram (EEG) was observed. At around 23 degrees C nasopharyngeal temperature the tracing became almost flat and remained so throughout the hypothermic CPB or the PBP under hypothermic CPB. Consistent recovery of the EEG was, however, observed during the period of rewarming on the CPB, and the voltage and frequency of the EEG recovered to control levels on weaning off CPB at 36 degrees C in both groups. In the PBP group, the cerebral arteriovenous oxygen (AVO2) difference was 12.4 +/- 4.0 vol% before beginning the CPB, and it was 5.6 +/- 2.7, 5.7 +/- 3.1, 5.4 +/- 3.3, and 4.9 +/- 2.9 vol% at 10, 30, 60, and 90 min respectively after commencement of the PBP under hypothermic CPB. The cerebral AVO2 difference measured 10 min after commencement of the PBP was significantly less than that in the control group (P less than 0.05), but otherwise there were no significant differences between cerebral AVO2 differences in the two groups. Concentration of serum creatine kinase-BB (CK-BB) gradually increased in proportion to the duration of CPB in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Congenital quadricuspid aortic valve associated with aortic regurgitation.

A case of quadricuspid aortic valve is described. The aortic valve consisted of 3 equal-sized and 1 smaller cusps, and a supernumerary cusp located between the right and noncoronary cusps. A right coronary ostium was close to the accessory commissure, and in a lower position. Three fenestrations were found at the supernumerary commissure. Aortic valve replacement was performed successfully with a St. Jude Medical prosthetic valve. On histological examination, the resected cusps showed fibrotic thickening with calcification and no sign of previous inflammatory disease. Quadricuspid aortic valve must be considered a malformation capable of leading to severe valve failure in later life.

Aortic Valve↗
PubMed1992

Modified De Vega's annuloplasty for functional tricuspid regurgitation--early and late results.

From 1978 through 1987, 321 patients who had functional tricuspid regurgitation (TR) associated with mitral or combined mitral and aortic valve disease underwent tricuspid annuloplasty with our modification of the original De Vega's annuloplasty technique. The modified De Vega's annuloplasty consisted of two separate semicircular sutures placed around the anterior and lateral aspect of the tricuspid valve. Preoperatively, 229 (71.3%) of the 321 patients were in New York Heart Association functional class III or IV. There were nineteen early deaths (5.9%), and 15 patients died during a follow-up period of 15 to 126 months (mean follow-up, 26 months). Five patients (1.5%) required reoperation because of biological mitral valve failure and recurrence of mitral stenosis. The severity of TR was evaluated by two-dimensional and pulsed Doppler echocardiography, and was classified on a scale of 0 to Grade 3 according to the maximal distance and the flow pattern of the regurgitant signals in the right atrium. Postoperative echocardiographic evaluation of TR was performed in 121 randomly selected patients late after operation. TR reduced to Grade 1 or less in 107 (88.4%) of the 121 patients after operation. Ninety-six percent of the survivors were in New York Heart Association functional class I or II, postoperatively. The actuarial survival rate for the 321 patients with the modified De Vega's annuloplasty including early deaths was 88.2% at 10 years and the actuarial rate of freedom from reoperation on the tricuspid valve was 97.6%. Our surgical experience indicated that the modified De Vega's annuloplasty, as the method of first choice, is a simple, reliable procedure and resulted in reduction of the severity of TR in 88.4% of the patients with functional TR.

Adult↗
PubMed1992

[A device for hepatic arterial catheterization using saphenous vein graft].

We performed regional arterial infusion chemotherapy for hepatocellular carcinoma by retaining a hepatic arterial reservoir. The catheters were placed via gastroduodenal artery and positioned at the junction with common hepatic artery during operation. But we encountered many complications and did not perform regional arterial infusion chemotherapy. This time we cannulated through the saphenous vein graft by which hepatic perfusion was maintained by the superior mesenteric artery; we did not cannulate through the common femoral artery using a subcutaneously implanted reservoir. Venous arterial anastomosis is performed with interrupted (7-0 Prolene) vascular suture. Postoperative angiography by the reservoir showed total hepatic perfusion. There have been no instances of hemorrhage, thrombosis, or catheter dislodgement with this technique. Duration of follow-up varied from 2 to 7 months.

Carcinoma, Hepatocellular↗
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

[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

Purification of nitric oxide synthase from rat macrophages.

Nitric oxide (NO) synthase (EC 1.14.23) has been purified to apparent homogeneity from rat macrophages. The purification procedure involves affinity chromatography with adenosine 2',5'-diphosphate-agarose and gel filtration chromatography on a Superose 12 HR 10/30 column. The apparent molecular weight is 300,000 by gel filtration. On polyacrylamide gel electrophoresis in sodium dodecyl sulfate, the enzyme migrates as a single protein band with Mr = 150,000. The purified enzyme is colorless, and an absorption maximum is observed at 280 nm. The half-life of the enzyme activity is 6 h at pH 7.4 and 4 degrees C. The enzyme activity required the presence of NADPH, (6R)-5,6,7,8-tetrahydro-L-biopterin, and dithiothreitol. Although the cerebellar and endothelial enzyme require Ca2+ and calmodulin, these are not required by the macrophage enzyme. The macrophage nitric oxide synthase (an inducible enzyme) seems to be different from the cerebellar and endothelial enzyme (a constitutive enzyme).

Amino Acid Oxidoreductases↗
PubMed1991

Calmodulin-independent nitric oxide synthase from rat polymorphonuclear neutrophils.

Recently, the purification of nitric oxide synthase (EC 1.14.23) from rat cerebellum has been reported, and the enzyme is a calmodulin-requiring enzyme (Bredt, D. S., and Snyder, S. H. (1990) Proc. Natl. Acad. Sci. U. S. A. 87, 682-685). In this paper, nitric oxide synthase has been purified to near homogeneity from the cytosol fraction of rat polymorphonuclear neutrophils. The purification procedure involves affinity chromatography with adenosine 2',5'-diphosphate-agarose and an anion exchange column, DEAE-Bio-Gel A. On polyacrylamide gel electrophoresis in sodium dodecyl sulfate, the enzyme migrated as a single protein band with Mr = 150,000. The molecular weight was estimated to be 150,000 by gel filtration on a Superose 12 HR 10/30. The purified enzyme was unstable with a half-life of 3 h at pH 7.4 and 4 degrees C. The enzyme activity required the presence of Ca2+, NADPH, FAD, and (6R)-5,6,7,8-tetrahydro-L-biopterin. Calmodulin antagonists (W5, W7, W13, and trifluoperazine dihydrochloride) did not inhibit the enzyme activity, and the addition of calmodulin was also ineffective for the increase in the enzyme activity. The neutrophil enzyme appears to be a calmodulin-independent type of nitric oxide synthase.

Amino Acid Oxidoreductases↗
PubMed1991

Primary anastomosis for acute ascending aortic dissection.

Intimal tear resection and primary anastomosis of the aorta were used for the treatment of eight patients with DeBakey I and II type acute aortic dissection. Five patients were of DeBakey I type, and three patients were of the II type. Moderate or severe aortic regurgitation (AR) was observed in six of eight patients. The site of the intimal tear was diagnosed by intraoperative echocardiography, and the adventitia corresponding to the intimal tear was transversely opened under total cardiopulmonary bypass. While resuspension of the aortic valve was performed on only one of six patients, AR disappeared in four, postoperatively. Two of eight patients died early postoperatively. The cause of death was postoperative cardiac tamponade in one patient and cerebral herniation in the remaining one. The other six patients have been observed for a mean period of 27 months. There is no late death, and they show no dilatation of the aortic root and deterioration of AR. We believe that this operative method is a simple and safe emergency procedure for DeBakey I and II type acute aortic dissection.

Acute Disease↗
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

Cytosolic and membrane-bound nitric oxide synthase.

Cytotoxic activated macrophages were sonicated and centrifuged. The activity of nitric oxide (NO) synthase was present in the supernatant and independent of Ca2+. The pellets were washed three times and treated with buffer containing 0.1% Triton X-100 or buffer alone, followed by centrifugation. The supernatant containing Triton X-100 showed NO synthase activity that was dependent on Ca2+, whereas the supernatant without the detergent had little activity. These data suggest that there are two forms of NO synthase: cytosolic and membrane-bound enzymes.

Amino Acid Oxidoreductases↗
PubMed1991

Reoperation for acquired valvular heart disease--operative method and surgical results.

Between January, 1982 and December, 1989, 102 reoperations (repeat median sternotomy) in 101 patients with valvular heart disease were performed at Kurume University Hospital. In these operations, the heart was not mobilized from the pericardium to prevent tearing the heart or great vessels. All operative procedures were performed through the pericardium which adhered tightly to the heart. Adequate left ventricular hypothermic protection was obtained without total dissection of the heart by cold crystalloid cardioplegic solution and topical cooling which was accomplished by filling the left pleural space with cold saline during the operation. As to the surgical results, the early mortality rate was 4.0%, and the late mortality rate was 5.2%. The causes of death were not related to the operative procedures or perioperative myocardial protection. There was no significant difference in the early mortality rate between the reoperations and the initial operations. These results suggest that reoperation for valvular heart disease should be performed before the hemodynamic condition of the patient deteriorates.

Adult↗
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↗