Biomedical subjects

K Kawachi

Publications and source records attributed to K Kawachi.

At least 19 recordsLinked to original sources

PubMed1992

Internal thoracic artery grafting for congenital coronary malformations.

We report 2 patients with congenital coronary anomalies (atresia of left main coronary artery and anomalous origin of the left coronary artery from the pulmonary artery) successfully treated with single or double internal thoracic artery grafting. Because the internal thoracic artery has a potential for circumferential as well as longitudinal development, and because of the uncertainty of ultimate vein graft function, we believe that the internal thoracic artery is the best graft material for the treatment of congenital coronary malformations requiring bypass operation in children, adolescents, or even in adults.

Child↗

PubMed1992

Angiographic demonstration of no-flow anatomical patency of internal thoracic-coronary artery bypass grafts.

To clarify the no-flow situation of the stringlike internal thoracic artery graft, we angiographically examined such grafts by temporarily occluding the recipient coronary artery with a percutaneous transluminal coronary angioplasty balloon and were able to reveal anatomical patency of the internal thoracic artery graft in 2 patients 1 year and 3 years after the operations. Thus, there is a possibility that internal thoracic artery grafts may continuously maintain anatomical patency even under no-flow situations just like nonfunctioning collateral vessels and may function properly later as a graft when the native coronary flow decreases. Also, this angiographic technique can be a new method for detecting anatomical patency of no-flow and functionally closed internal thoracic artery grafts.

Anastomosis, Surgical↗

PubMed1992

Effects of hormonal supplements on the maintenance of cardiac function in potential donor patients after cerebral death.

It is well-known that cardiac function in cerebrally dead patients rapidly deteriorates, leaving the organ unfit for donation. This study investigated whether or not cardiac function in patients with cerebral death can be maintained in a desirable condition with hormonal supplementation. In studies of changes in hormones before and after cerebral death, insulin, glucagon, triiodothyronine, thyroxine, cortisol, vasopressin, epinephrine, and norepinephrine values were measured with a lapse of time after cerebral death. Among them, triiodothyronine and cortisol levels were markedly reduced after cerebral death; therefore, these two hormones were selected as hormonal supplements. The average period from the judgment of cerebral death to cardiac arrest was 4.3 days in 12 patients with no hormonal supplement (group I) and more than 11.5 days in 4 patients with hormonal supplement (group II). This period for patients in group II was significantly longer (p less than 0.05). In 2 of the group II patients the hormonal supplementation was discontinued at the family's request, and in the other 2 patients, it was discontinued because of proposed renal donation. Hemodynamic comparisons between the two groups showed that the mean arterial pressure and the left ventricular maximum dp/dt were significantly higher (p less than 0.01) as was the cardiac index (p less than 0.05) on the 3rd day after cerebral death in members of group II. Thereafter, in group II, an excellent hemodynamic state was maintained until hormonal supplements were discontinued. We conclude that the triiodothyronine and cortisol supplements were effective in the maintenance of cardiac function in patients after cerebral death.

Adolescent↗

PubMed1992

[Late results of coronary artery bypass grafting with the internal thoracic artery].

Between November 1981 and December 1991, 755 patients underwent isolated coronary artery bypass grafting. We compared postoperative events, graft patency and survival rates of the patients who received at least one internal thoracic artery graft (n = 517) with those of the patients who had only saphenous vein bypass grafts (n = 238). No significant difference was found between the 2 groups in patient's age at the operation, female ratio and the incidence of emergency operation. The operative mortality was not significantly different in either group. Graft patency was better for internal thoracic artery grafts than for SVG (ITA grafts 97.1%, SVG 85.6% p less than 0.0001). Graft-LAD patency rate was also better for ITA grafts than for SVG (ITA grafts 97.7%, SVG 86.8%, p less than 0.0001). The incidence of late cardiac events (late cardiac death, reoperation, myocardial infarction) is lower in patients with ITA. Furthermore, patients who received ITA grafts had a better survival rate at 8 years (91.1% versus 85.3%, p = 0.048) than those who had vein bypass grafts alone. We conclude that the use of ITA grafts enhances the long-term benefits including long-term survival rate. This is the first observation in Japanese population.

Adult↗

PubMed1992

[Left ventricular performance after patch reconstruction of the left ventricular wall for postinfarction left ventricular aneurysms].

Left ventricular performance in patients with a left ventricular aneurysm (LVA) treated with patch reconstruction is largely unknown. This study consisted of 15 patients, 14 men and 1 woman, with the average age of 59 +/- 8.5 years. The resected area of LVA was 40 +/- 27 cm2. The area of the woven Dacron patch used for reconstruction was 57 +/- 19% of the resected area including the sewing rim. The EF (Ejection Fraction, 1/3FF (Filling Fraction) and PFR (Peak Filling Rate) were calculated by 99mTc equilibrium cardiac pool scintigraphic images. The A/R ratio (peak velocity during atrial kick phase/peak velocity during the rapid filling phase) was measured using Doppler echocardiography, at the mitral orifice level. These parameters were determined before and 1 to 2 months after the operation. The time course was followed for A/R ratios. The preoperative resting global EF was 0.28 +/- 0.14 (0.44 +/- 0.13 for the contractile area) and the EF during exercise was 0.31 +/- 0.14. Resting and exercise EFs improved significantly (p < 0.01) to 0.40 +/- 0.11 and 0.43 +/- 0.10 postoperatively. The 1/3FF (%) and PFR (/sec) were low before operation (1/3FF, 11.3 +/- 8.3; PFR, 1.2 +/- 0.47). Postoperatively, the 1/3FF rose to 14.8 +/- 9.3 and the PFR showed a significant (p < 0.05) increase to 1.6 +/- 0.6. The A/R ratio significantly (p < 0.05) improved from preoperative 1.76 +/- 0.46 to 0.95 +/- 0.11 on the 3rd postoperative day. This improvement was maintained until the late postoperative period, with a value of 1.14 +/- 0.29 at month 16.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1992

A quantitative study of postoperative luminal narrowing of the internal thoracic artery graft in coronary artery bypass surgery.

We used quantitative angiography to determine the postoperative diameter of the internal thoracic artery graft at the point close to the anastomosed site in 147 patients who received the graft for the left anterior descending coronary artery. We performed generalized multiple linear regression analysis (Type I quantification method) to assess the effects of the following factors on the internal thoracic artery graft diameter: age, gender, time of angiography, laterality of the internal thoracic artery used, presence of an undivided major side branch of the internal thoracic artery, presence of a saphenous vein graft having blood flow competition with an internal thoracic artery graft, presence of distal stenosis of the recipient left anterior descending coronary artery, severity of postoperative left anterior descending coronary artery stenosis, and presence of coronary risk factors. The standardized category scores for 25% left anterior descending coronary artery stenosis, 50% left anterior descending coronary artery stenosis, and presence of a saphenous vein graft having blood flow competition with an internal thoracic artery graft were -1.418, -0.767 and -0.622, respectively. Thus, the internal thoracic artery diameter was smaller in patients with well-preserved flow of the recipient coronary artery. The internal thoracic artery diameter had a particularly strong correlation with the degree of left anterior descending coronary artery stenosis (partial correlation coefficient: 0.670). The other factors seemed to have little or no correlation with the postoperative internal thoracic artery diameter. With the criterion that the internal thoracic artery diameter below 1.0 mm represents the "string sign" of internal thoracic artery graft, this phenomenon was observed in nine patients (6.1%). In all of these patients, left anterior descending coronary artery flow was well-preserved, and no ischemia was disclosed in the left anterior descending coronary artery-perfused area. These results indicate that internal thoracic artery grafts have flow adaptability responding to the flow demand of the recipient coronary artery and that the string sign of internal thoracic artery grafts is mainly an outcome of its physiologic characteristics.

Adult↗

PubMed1992

[Aortic valve replacement with fresh or cryopreserved aortic allograft--initial experience in Japan].

Aortic allograft valves were harvested from non-infected (bacterial or viral) cadavers within 24 hours of death with a family consent, and were sterilized by 4 degrees C antibiotic solution for 48 hours. Then, the allograft was preserved in the 4 degrees C nutrient medium (fresh; TC-199, calf serum and HEPES buffer) or in liquid nitrogen (-196 degrees C) after freezing to -80 degrees C by a programmed freezer. 10% dimethylsulfoxide (DMSO) was used for cryopreservation. Following germ-free confirmation, aortic allograft valves were implanted in 5 patients having aortic regurgitation with good results. Three fresh and two cryopreserved allograft valves were used. Although the follow-up term is very short (maximum 1 year) at the present time, the valve function is quite satisfactory, confirmed by cardiac catheterization and echocardiography. This is the first report in Japan with regard to cryopreservation of allograft valves and clinical use of fresh or cryopreserved valves. We believe that realization and progress of allograft preservation by cryo-technique and establishment of the tissue bank are important for the development of cardiovascular surgery in Japan.

Adult↗

PubMed1992

[A successful case of thoracic aortic aneurysm with mixed cryoglobulinemia].

Cold-reactive proteins, such as cold agglutinins, cryoglobulins, and cryofibrinogens, are reversibly precipitates, or gel, upon exposure to cold temperatures. Cryoglobulins are usually not of importance, but under special conditions, such as surgical hypothermia, hyperviscosity and damage in microcirculation may occur in patients with high plasma concentration of cryoglobulins. Several groups have reported their efforts to reduce further the risks of surgical hypothermia in patients with cold agglutinins, but rarely in patients with cryoglobulins. A 57-year-old woman with thoracic aneurysm, requiring replacement of the ascending aorta and the aortic arch, had mixed cryoglobulinemia (cryocrit 29%) associated with rheumatoid arthritis. Steroids therapy and preoperative plasmapheresis were performed, and cryocrit levels were decreased until 0% before operation. Systemic hypothermia (25 degrees C), hemodilution techniques during cardiopulmonary bypass, and cold crystalloid cardioplegia were successfully employed, and no clinical evidence of microcirculation damage was posed after operation.

Aorta, Thoracic↗

PubMed1992

[Angioscopic prediction of late vascular patency after transluminal balloon angioplasty for arteriosclerotic obstructions of the artery of the lower extremities].

Arterial occlusion or stenosis of the lower extremity due to arteriosclerosis obliterans (ASO) was treated by transluminal balloon angioplasty (TBA). Angioscopic observation of the vascular lumen, performed immediately after TBA, provided five major findings: (1) abrasion of the intima, (2) irregularity of the lumen due to poor expansion, (3) laceration of the wall, (4) mural thrombus and (5) calcification. The degree of each of these abnormalities was scored with a 3-grade scale (0, 1 and 2), and scores for the 5 abnormalities were totaled in each patient. Analysis of the relationship between scores and postoperative vascular patency demonstrated that patients without vascular patency in the early (within 6 months) or late period (6 months or more) after the operation had higher total scores as compared to those in whom the vessel remained patient in the corresponding postoperative periods (p less than 0.01, p less than 0.05). Among others, patients with a total score over 5 showed markedly lower patency rates in the early period (10%) as well as late period (0%) after the operation (p less than 0.01). These results indicate the usefulness of post-TBA angioscopic observation of vascular lumen in predicting the long-term patency of the vessels operated on.

Aged↗

PubMed1992

[Intra-atrial implantation of mitral valve prosthesis in 2 patients with active infective endocarditis complicated by mitral annular destruction].

This is a report of two patients with extensive destruction of the mitral annulus due to active infective endocarditis. Patient 1 was a 66-year-old female and the patient 2 was a 59-year-old male. In both patients medical therapy had failed to control endocarditis and emergency mitral valve replacements were carried out. At the operation special surgical techniques were necessitated, since insertion of artificial valves in the annulus was impossible because of the lack of the annular tissue due to destruction and excision. On the posterior commissure side, mitral valve prosthesis were sutured to the left atrial wall just above the anatomical mitral ring. Furthermore, in patient 2, a bovine pericardium collar attached to the prosthetic valve was sutured to the left atrial wall to secure fixation of the prosthetic valve. The postoperative courses were uneventful in both patients. This technique seems to be useful in patients with mitral annular destruction.

Aged↗

PubMed1992

[Delayed sternal closure; a simple sternal splint].

A simple and inexpensive sternal splint for delayed sternal closure was described. Sternal edges were splinted open using an edge-cut disposable syringe. This method has been employed successfully in 10 patients (one adult, 9 children). This syringe splint is a simple, inexpensive and effective method for delayed sternal closure.

Child, Preschool↗

PubMed1991

Hemodynamics and coronary blood flow during exercise after coronary artery bypass grafting with internal mammary arteries in children with Kawasaki disease.

BACKGROUND: Saphenous vein grafts (SVG) and internal mammary artery (IMA) grafts have been used for coronary artery bypass grafting. In adult patients with bypass grafting for atherosclerotic coronary artery disease, IMA grafts have been reported to have long-term patency; however, results are conflicting on whether the graft is sufficient to meet increased myocardial oxygen demand during exercise. There have been no studies on hemodynamics and blood flow during exercise after bypass grafting with IMA in pediatric patients with Kawasaki disease. METHODS AND RESULTS: We studied 17 pediatric patients with Kawasaki disease (average age, 7.5 +/- 3.1 years), who underwent coronary artery bypass grafting with the IMA. The average number of coronary artery bypass grafts was 2.1 +/- 0.7/patient. For all patients, the left IMA was anastomosed to the left anterior descending coronary artery; for eight patients, the right IMA was also anastomosed to the right coronary artery. In addition, 11 SVGs were used. The postoperative patency rates after 1 month were 100% with the IMA graft and 91% with SVG. One year after the operation, the patency rates were 100% with IMA and 50% with SVG. Hemodynamics during exercise were measured with a bicycle ergometer, and coronary sinus blood flow was measured by the continuous thermodilution method in six patients. The relation between delta LVEDP (the difference between left ventricular end-diastolic pressure at rest and during exercise) and delta SVI (the difference between the stroke volume index at rest and during exercise) was analyzed. Four of six patients had reduced cardiac function before operation (delta LVEDP, positive; delta SVI, negative). However, after the operation, all patients demonstrated improvements in cardiac function during exercise (delta LVEDP, positive; delta SVI, positive). Coronary sinus flow per left ventricular mass increased after operation from 70 +/- 46 to 87 +/- 56 ml/min at rest (p less than 0.05) and from 139 +/- 118 to 183 +/- 150 ml/min during exercise (p less than 0.05). CONCLUSIONS: In conclusion, this study reveals improvements in both hemodynamics and coronary blood flow during exercise after coronary artery bypass grafting with IMA grafts in pediatric patients with Kawasaki disease.

Adolescent↗

PubMed1991

[Hyperperfusion syndrome following bilateral aorto-carotid bypass--a study of transcranial Doppler].

A 22-year old female with Takayasu disease, who underwent bilateral aorto-carotid bypass surgery developed hyperperfusion syndrome postoperatively. Following the operation, convulsion and headache developed and mean velocity in the middle cerebral artery, measured by transcranial doppler, elevated. Mean velocity gradually decreased on the 10th postoperatively day and became a plateau at 200% of preoperative value. Pulsatility index as a index of cerebral vascular resistance was low just after the operation, became normal the following day and gradually increased 10 days after the operation. These changes seem to be recovery of cerebral autoregulation. On the 20th postoperative day, computed tomography scan was examined and multiple low density areas were found in the basal ganglia regions, but these changes disappeared 2 months after the operation. These reversible changes of CT scan might show ischemic changes or cerebral edema induced by cerebral vasospasm.

Adult↗

PubMed1991

[Perioperative monitoring of cerebral circulation in a patient with Takayasu disease].

Transcranial Doppler (TCD) and fiberoptic oximetry for continuous measurement of jugular venous oxygen saturation (SjO2) were used as perioperative monitoring of cerebral circulation in a patient with Takayasu disease who received bilateral aorto-carotid bypass. Following revascularization of the left carotid artery, mean velocity in the middle cerebral artery (MV) increased (lt 300%, rt 200% of control values) and SjO2 also increased. Following revascularization of right carotid artery, MV increased (lt 500%, rt 400% of control values) but SjO2 was unchanged. After bilateral revascularization, high velocity continued for about 10 days, and convulsion with headache occurred. Therefore hyperperfusion syndrome was suspected. By perioperative monitoring of MV and SjO2, it might be possible to evaluate intracranial hemodynamics, necessity of shunt operation as well as bilateral bypass, and postoperative hyperperfusion syndrome.

Adult↗

PubMed1991

[A case of ruptured distal arch aneurysm associated with postoperative unilateral respiratory disorders].

This paper describes a patient with ruptured distal arch aneurysm associated with postoperative unilateral respiratory disorders whose life was able to be saved by surgery. The patient was a 68-year old male who underwent emergency surgery due to sealed rupture of distal arch aneurysm while preparing for selective surgery. Artificial graft replacement of the distal arch was carried out under centrifugal pump bypass. Respiration was controlled using differential lung ventilation (DLV) techniques. This was done because weaning from the respirator was difficult due to decreases in lung-thorax compliance on the opened chest side after surgery. Weaning from the respirator was achieved on the 10th day of illness after surgery. Postoperative prognosis of ruptured thoracic aneurysm is extremely poor, with high mortality being attributable to the fact that most patients are elderly and the incidence of respiratory and cardiovascular complications is very high. In addition, problems are often encountered in postoperative respiration management in patients with thoracic aneurysm who need open chest surgery. DLV seems to be a useful support in such patients who have underlying respiratory disorders.

Aged↗

PubMed1991

[A case of bilateral internal thoracic artery bypass grafting in sudden death survivor with multivessel coronary spasms].

We report a 58-year-old male with a history of cardiac arrest due to coronary artery spasm, preoperative coronary arteriograms showed multivessel coronary spasm after the administration of ergonovine maleate associated with triple vessel fixed stenotic lesions. Under the use of cold diltiazem potassium-blood cardioplegic solution to prevent perioperative coronary spasm, coronary artery bypass grafting was performed. The right internal thoracic artery (ITA) was anastomosed to the left anterior descending artery and the left ITA to the circumflex artery. A saphenous vein graft was anastomosed to the right coronary artery. The postoperative course was uneventful. In postoperative coronary angiography with ergonovine stimulation, neither ITA grafts showed spastic changes, and the coronary artery distal to the anastomotic sites were well perfused through the ITA grafts. The patient has been free of angina without administration of calcium antagonist and been doing well for 2 years and 5 months since the operation.

Coronary Artery Bypass↗

PubMed1991

[A quantitative angiographic study of characteristics of internal thoracic artery grafts in coronary artery bypass surgery].

In adult patients with atherosclerotic coronary artery disease and in pediatric patients with Kawasaki heart disease, characteristics of internal thoracic artery grafts (ITA grafts) used for coronary artery bypass grafting (CABG) were quantitatively assessed by postoperative angiography. In 142 adult patients with a ITA graft for the left anterior descending artery (LAD), the diameter ratio between ITA graft and recipient LAD at the point close to the anastomotic site (ITA/LAD diameter ratio) was determined by postoperative angiography. This ratio for the adult patients as a whole was 1.04 +/- 0.34. The multivariate analysis (Quantification I) was performed to assess the effects of the following 12 factors on the ITA/LAD diameter ratio: (1) age at the time of operation, (2) sex, (3) time-duration from the operation to angiography, (4) laterality of the ITA used, (5) presence of an undivided major side branch of the ITA graft, (6) presence of blood flow competition between the ITA graft and other grafts, (7) presence of distal stenosis of the recipient LAD, (8) severity of LAD stenosis after the operation, and (9-12) presence of hyperlipidemia, diabetes mellitus, hypertension, or smoking history. The standardized category scores of 25% LAD stenosis, 50% LAD stenosis, and blood flow competition between the ITA and other grafts were -0.815, -0.359, and -0.306, respectively. Insignificant stenosis of the recipient coronary artery was associated with reduction of the ITA/LAD diameter ratio, and this ratio strongly correlated with the severity of LAD stenosis (partial correlation coefficient: 0.627). However, no other factors significantly influenced on the ITA/LAD diameter ratio. In 15 pediatric patients, the length and diameter of 19 ITA grafts and 5 saphenous vein grafts (SVGs) which remained patent in the early (about one month) and late (14 +/- 4 months) postoperative period were determined. Only in the ITA graft, increases in graft length and diameter associated with patient growth were recognized. In the present study, the physiological characteristics of the ITA graft were demonstrated as a viable conduit with flow adaptability and growth potential.

Adult↗

PubMed1991

[A penetrating cardiac wound by a flying metallic fragment].

A 54-year-old man suddenly felt a strike on his chest while mowing with a machine. At first he had no symptoms except for wound pain, but several hours later, he suffered from high fever with chilliness. The chest roentgenogram showed a foreign body localized within the cardiac shadow. The echocardiogram revealed that the metallic fragment was embedded in the inferior wall of the left ventricle. It appeared that the fragment entered the left ventricular cavity through his anterior chest wall, the right ventricular outflow tract and the ventricular septum. At the operation, the location of the foreign body was again confirmed by the intraoperative echocardiography and the fragment was successfully removed through a left ventricular incision under cardiopulmonary bypass. The postoperative course was uneventful and the case was reported with a review of the literature.

Echocardiography↗