Search PubMed⌕ Search

Biomedical subjects

O Matsuki

Publications and source records attributed to O Matsuki.

33 records · Page 2Linked to original sources

New surgical technique for total-defect aortopulmonary window.

A new technique is described to repair aortopulmonary window with total defect in an 8-day-old baby. Because we expected the future growth of aorta, we used the anterior wall of the pulmonary artery as a large flap to reconstruct the posterolateral aortic wall. An equine pericardial patch was used to repair the defect in the pulmonary artery. This is a logically effective method for aortic reconstruction in a neonate with a large aortopulmonary septal defect.

Aortopulmonary Septal Defect↗

[Open heart surgery without homologous blood transfusion in small children of body weight less than 20 kg].

In 28 children with congenital cardiac lesions, open heart surgery was attempted without homologous blood transfusion using extreme hemodilution for cardiopulmonary bypass (CPB) and moderate to profound hypothermia. The entry criteria for this study were preoperative hemoglobin value above 10 g/dl and expected CPB time of less than 120 minutes. Acyanotic heart diseases such as ventricular or atrial septal defect were the main lesion, but some cases of tetralogy of Fallot and single ventricle were also included in this study. Intraoperative saving of autologous blood and autotransfusion using cell saver were carried out in a part of the subjects. Acceptable lowest values for hemoglobin was 4-5 g/dl and 40% for mixed venous oxygen saturation. As the results, 18 patients tolerated CPB without transfusion and eventually 16 patients were discharged without transfusion at all. The body weight for those without transfusion was 13.9 kg in average and the lowest was 6.8 kg. The significant factor affecting the needs for homologous blood transfusion was prolonged CPB time over 120 minutes. Although there was a tendency that the patients with body weight less than 15 kg received transfusion more frequently than those with body weight more than 15 kg, the body weight was not necessarily a limiting factor. Pre-CPB blood saving and intraoperative autotransfusion were the positive factors for successful non-transfusion open heart surgery.

Blood Transfusion↗

Hand-made valved conduit with high-porosity knitted graft and glutaraldehyde-treated autologous pericardial trileaflet valve.

In 10 patients with various congenital heart defects requiring reconstruction of right ventricle to pulmonary artery continuity, a new hand-made valved conduit was introduced. To avoid late stenosis with peel formation of the graft, high-porosity Golaski knitted graft was chosen. The graft was sealed by fibrin glue, and autologous pericardium was treated with glutaraldehyde and used to construct a trileaflet valve inside the graft. This hand-made graft was pliable with good conformability. The valve function was found good in the intermediate follow-up in 8 patients. This composite valved conduit may be a good alternative to the xenograft valved conduit when allograft conduit is not available.

Bioprosthesis↗

Viable and nonviable aortic homografts in the subcoronary position: a comparative study.

One hundred fifty-five freeze-dried, 63 frozen, and 337 Hanks'-antibiotic solution preserved or nutrient-antibiotic solution preserved homografts used for isolated aortic valve replacement have been followed for 1 to 20 years (mean, 5.3 years), a total of 2,931 patient-years of follow-up information. Overall survival, valve-related death, primary tissue failure, failure due to surgical technical error, infective endocarditis, and overall event-free survival have been assessed and compared. Overall survival 20 years after operation was 51.6% +/- 8.1% with a low incidence of sudden death. The method and length of preservation did not have any effect on the long-term performance or the mode of failure of the homografts. The rate of primary tissue failure was apparently higher with valves preserved in a solution containing calf serum, but the difference was not significant. It is concluded that long-term patient survival and quality of life after aortic valve replacement with a homograft are excellent. The current study, however, could not verify the existence of a significant difference between the three assessed methods of homograft preservation. Furthermore, it could not prove the importance of cellular viability or the existence of clinically significant immunological factors other than the calf serum content of the nutrient medium.

Adult↗

Long-term performance of 555 aortic homografts in the aortic position.

Long-term results with 555 aortic homografts used for isolated aortic valve replacement (AVR) between 1964 and 1986 were analyzed to assess valve performance and the time-related onset of valve-related events. The total follow-up was 2,931 patient-years. Twenty years after operation, overall survival was 51.6 +/- 8.1%, freedom from valve-related death was 67.1 +/- 8.9%, freedom from primary tissue failure was 12.4 +/- 4.8%, freedom from infective endocarditis was 82.7 +/- 4.3%, freedom from surgical technical failure was 88.1 +/- 2.3%, and freedom from all complications including valve-related death was 9.0 +/- 3.5%. The incidence of thromboembolism was 0.034% per patient-year (one potential event). Long-term results after homograft insertion for aortic stenosis were significantly better than those after insertion for aortic incompetence. It is concluded that the good quality of life and the median life expectancy, which extends more than 20 years after operation, make the homograft an excellent choice for AVR.

Actuarial Analysis↗

Early and late results of aortic root replacement with antibiotic-sterilized aortic homograft.

Between November 1972 and November 1986, 108 patients aged 5 to 73 years had complete replacement of the aortic root with an aortic homograft into which the coronary arteries were implanted. The main indications were (1) a tunnel type of aortic obstruction involving a hypoplastic ring, (2) a para-aortic annular abscess, (3) prosthetic valve dysfunction, mainly a previous aortic homograft, and (4) aortic stenosis with a small aortic anulus. Eighty-four patients (78%) had previous aortic valve operations. Concomitant cardiac procedures were done in 34 patients (32%). The 30-day mortality rate was 14% (15 patients). The cumulative follow-up period was 180.3 patient-years. The late mortality rate was 6.1% per patient-year (11 patients). The patients were not given anticoagulants postoperatively, but the entire group has been completely free from thromboembolism. The actuarial 5-year survival rate including operative deaths was 72%. The freedom from valve-related death at 5 years after operation is 86% and freedom from reoperation at 5 years is 96%. The use of homografts for replacement of the aortic valve and root in patients with complex lesions affecting these structures has shown encouraging early and late results, with regard to both survival and valve performance.

Actuarial Analysis↗

Two decades' experience with aortic valve replacement with pulmonary autograft.

Aortic valve replacement with a pulmonary autograft was performed on 241 patients between June 1967 and October 1986 at National Heart Hospital, Guy's Hospital, Middlesex Hospital, Harley Street Clinic, and Italian Hospital in London by one of the authors (D.N.R.). The longest follow-up is 18 years 7 months, and the cumulative total follow-up is 1130 patient-years (pt-yr). The overall 30-day mortality rate is 6.6% (16 patients), with no deaths after 1976, and the late mortality rate is 1.7%/pt-yr (19 patients). The actuarial survival rate is 57.3% +/- 9.6% at 19 years. No anticoagulation has been used and there have been no thromboembolic episodes. The incidence of bacterial endocarditis is 1.2%/pt-yr (14 patients), and its actuarial event-free rate is 74.2% +/- 8.1% at 19 years. Reoperation because of failure of the pulmonary autograft was performed on 36 patients, 27 of whom needed valve replacement. The incidence of pulmonary autograft replacement is 2.5%/pt-yr, and its actuarial event-free rate is 48.5% +/- 13.7% at 19 years. For reconstruction of the right ventricular outflow tract, 186 aortic homografts, 26 pulmonary homografts, 16 autologous fascia lata valved conduits, 7 autologous pericardial conduits with or without a valve, and 6 xenograft valved Dacron conduits were used. Thirty-one patients were reoperated on, mostly because of degeneration of this material. Pulmonary rather than aortic homografts are now favored for reconstruction of the right ventricular outflow tract Because of its satisfactory long-term result without the need for anticoagulation, as well as its safety as an established surgical procedure, this operation can be recommended to a wider range of patients.

Actuarial Analysis↗

Imaging analysis of platelet deposition on the extracardiac valved conduit in humans.

In 14 patients (aged 2-29 yr) with Hancock (n = 11) or Carpentier-Edwards extracardiac valved conduits (n = 3), platelet deposition (PD) was investigated using indium 111 (111In) platelet imaging. Repeated studies were performed in five patients. By visual analysis, 71% (5/7) of the imagings (7 images/5 patients) showed PD at early study 1-3 months after surgery, 9% (1/11) at intermediate study at 6-46 months (mean 21 mon) (11 images/10 patients) and 0% at late study at 81-132 months (3 images/3 patients). Quantitative analysis was made using relative ratio of radioactivity at the graft area to the area of the brachiocephalic artery (platelet accumulation index or PAI). The PAI was 1.85 +/- 0.47 (mean +/- SD) at early study, 1.51 +/- 0.23 at intermediate, and 1.36 +/- 0.37 at late study (NS). There was no significant difference in the late pressure gradients across the conduit (16-68 mon postoperatively) between the two groups with (n = 3) and without (n = 5) PD at the early stage (1-18 mon postoperatively, n = 8). The result may indicate that PD to the valved conduit in the right ventricular (RV) outflow tract occurs early postoperatively (mostly within 3 mon). The relationship of the PD detected by this method to late obstruction was not clarified in this study.

Adolescent↗

A new method of assessing left ventricular function under assisted circulation using a conductance catheter.

A new method of assessing left ventricular (LV) systolic function without terminating assisted circulation (AC) was investigated using a LV volume catheter (conductance catheter) in canine cardiopulmonary bypass (CPB) (Group 1, n = 7) and left heart bypass (LHB) (Group 2, n = 5) models. The hearts were subjected to either 20 min of global ischemia (IS), with a subsequent 80 min of reperfusion under CPB, or regional IS under LHB. Instantaneous LV pressure-volume data acquisitions were repeated during transient (15 sec) acute volume loading without terminating bypass. The relationship between the stroke work (SW), determined as the area of the pressure-volume loop, and the end-diastolic volume (EDV), were highly linear at every study point (mean: r = 0.956-0.986 in Group 1, r = 0.974-0.987 in Group 2). The slopes of SW and EDV (preload recruitable stroke work: PRSW) significantly decreased after IS, in both Group 1 and Group 2. In conclusion, measurement of PRSW without terminating bypass seemed to be useful in evaluating LV systolic function in patients under AC.

Animals↗

Elevation of mouse liver glutathione level by low-dose gamma-ray irradiation and its effect on CCl4-induced liver damage.

We examined the elevation of glutathione (GSH) levels in the liver of C57BL/6 female mice after low-dose r-ray irradiation and its inhibitory effect on CClI4-induced liver damage. The liver GSH level increased soon after irradiation with 50 cGy of gamma-rays, reached a maximum at around 12 post-treatment, and returned almost to the control level by 24 h. The activities of glutathione reductase, and glutathione peroxidase also showed the same pattern of change, while the activity of gamma-glutamylcysteine synthetase showed a gradual increase up to 24 h. The effect of pre-irradiation on CCl4-induced liver damage was also investigated. The activities of glutamic oxaloacetic transaminase and glutamic pyruvic transaminase in serum were markedly increased 12 h post-treatment with CCl4. Both increases were significantly suppressed by a single low-dose pre-irradiation. Malondialdehyde, a marker of lipidperoxidation, was also greatly elevated after CCl4 treatment, and its increase was suppressed by irradiation. These results suggest low-dose gamma-ray irradiation might be effective for the prevention of and/or therapy of various reactive oxygen species-related diseases including cancer.

Animals↗