We experienced acute renal failure after open heart surgery in 57 cases. Incidence of ARF was 3.31%, andmotality of this was 57.9%.
For the pourpose of data analysis, patients were seregrated into four groups by the period: Eearly period (before cardioplegia), Middle period (after cardioplegia), Late period (after pulsatile CPB). In late period incidence of ARF decreased, but motality of ARF increased. Pulsatile CPB was useful for the preventation of ARF. But, because of increase of serious patient, motality of ARF increased. Significant risk factors of ARF included pre operative renal dysfunction, severe heart failure, aging, long time CPB, and postoperative LOS.

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Clinical and hemodynamic results of aortic valve replacement using Omniscience valve in 33 patients were presented. The overall clinical results were good. And the postoperative hemodynamic studies disclosed the satisfactory cardiac performance, but the effective aortic valve area during exercise showed mild stenotic status. Omniscience valve has proved to be favorable in clinical use, but a longer follow up is still necessary to determine the thrombogenesity and durability.

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219 patients undergoing valve replacement with Hancock porcine bioprosthetic and another type of prosthetic valve, were evaluated. Cumulative follow-up is 627 patient-years (mean 3.1 years). Hospital mortality was 6.4%. Late mortality was 2.2% per patient-year; overall actuarial survival was 85 ± 3% at 4 years and no death thereafter. The incidence of emboli was 2.6% per patient-year for all patients with bioprostheses alone. There were two fatal cerebral emboli (0.3% per patient-year). There were no emboli for all patients with aortic valve replacement under no anticoagulant therepy. Primary tissue failure occurred in 3 patients; 2 were younger than 15 years old. Five patients had valve failure secondary to endocarditis. Actuarial late survival free from primary tissue failure was 98 ± 1% at 4 years, and 88 ± 9% at 7 years. The incidences of thromboembolism and primary tissue failure remain acceptably low through 7.5 years of follow-up period. From these results, we conclude that the Hancock valve is still a choice for cardiac valve replacement.

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This study was made as the basic research for the development of the new tri-leaflet valve prosthesis. The optimum tilt angle of the leaflet was studied through stress analysis and hydrodynamic simulation, and was 21 deg.. The role of the coaptation zone was “safety coefficient” for suturing the non-stented trileaflet valve. Coefficient of energy loss of stented tri-leaflet valve was larger than that of non-stented valve. This tendency increased when the valve diameter was below 19mm. It is important in clinical application of tri-leaflet valve prosthesis.

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We reported about the hemodynamic evaluation of the twenty one patients. The valve function was the best in the patients with the mitral regurgitation and the combined stenosis and regurgitation implanted by the Ionescu-Shiley valve of which the valve diameter was 31 and 33mm. The mitral valve mean diastolic gradients were 8.33±3.21mmHg in 25 and 27mm. 4.60±1.54mmHg in 29mm, and 3.17±1.08mmHg in 31 and 33mm valve diameter.

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To evaluate the clinical usefulness of atrial pacing (AP) in SSS, we studied clinical symptoms, cardiac size (CTR) and treadmill exercise tolerance (TXT) in 28 SSS pts, who were devided into two groups, AP (15 pts, mean age 58yrs) and ventricular pacing (VP: 13 pts, mean age 63yre) groups. After pacemaker implantation, no cardio-cerebral symptoms were observed in either group, and dyspnea obserbed preoperatively in or dinary daily activities remained in 2 of AP and 7 of VP group. CTR significantly decreased in AP (P<0.01) but remained unchanged in VP. TXT was greater in AP than in VP (P<0.05). In conclusion, atrial pacing seems to be a more effective and physiological means of the management of SSS than ventricalar pacing.

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To study a relationship between SF and EAP, we recorded EAP and estimated SF during Treadmill exercise in 16 SSS mean aged 58.9 years. All cases were classified into 3 groups, group I (n=6) had complete SF, group II (n=5) had incomplete SF which was rate-dependency and group III (n=5) showed undersensing of every spontaneous beat. EAP of group I was 2.25±1.05mv, group II was 1.40±0.67mv and group III was 0.54±0.09mv. There were significant differences between group I or II and III (p<0.01, p<0.05, respectively). The undersensing of AP was caused by decreased EAP in SSS who had associated atrial damage.

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Until Apr. 1982, we have implanted 365 generators and 250 leads in 222 cases. The ratio of generator failure was 7.3% in non-PPG, 0.6% in PPG and 0.8% in MPPG. The ratio of lead fracture was 20% in myocardial leads and 3.6% in catheter leads. Conclusion: 1). Addition of programmability has not resulted in the increase of generator failure. 2). The ratio of myocardial lead fracture is higher than that of catheter lead fracture.

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Systolic-time intervals and QRS morphology were studied in 52 patients with right ventricular pacing. In the patients who showed PEP/ET<0.8 (group I) and ≥ 0.8 (group II) subsequent PEP/ET remained<0.8 and ≥ 0.8, respectively. PEP was found a main determinant for separating both groups. LBBB type QRS was found only in group II. PEP/ET was smaller in the patients with downward QRS in V₆, was larger in those with upward QRS in V₆, and was between the former two in those with equally biphasic QRS in V₆. These results may suggest that QRS morphology influence cafdiac performance through electrical activation process.

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A 68-years-old man was undergone pacemaker implantation due to complete A-V block at his age of 59. He was pointed out cancer of the prostata with multiple bone metastasis, so the prostata and the both testis were resected in January 1982. The pacemaker was replaced with Spectrax^(R) 8423, a programable pacer. After that he was treated with extracorporeally induced systemic hyperthermia four times. During the treatment, pule rate of the pacer was programed 100 to 120 according to body temperature. The hemodynamic data and oygen consumption were analysed and found stable and safe enough.

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Intraoperative autotransfusion was undertaken in 44 cases of the surgery of great arteries using by our own designed autotranfusion apparatus and could be saved 60 percent of the total blood loss and was re-infused by this mean. Major side effect such as hemolysis or impaired coagulation, renal dysfunction and microembolization was not encountered, the maneuver of intraoperative application was technically feasible and easy. We stress that autotransfusion procedure is not only minimized the amount of blood transfusion but also prevent complications which associate with blood transfusion itself. Keywords Intraoperative autotransfusion. Hemolysis. Bleeding tendency, Microembolization, Swank filter

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A new type blood filter (NS-filter) of polyester mesh were designed and various experimental studies were performed. These results revealed that NS-filter was an excellent filter. Therefore, we compared NS-filter with the Darcron Woll Filter (Swank-filter) known to be excellent for removal of microaggregates composed of platetes, white blood cells and fibrin which form during blood storage. The rate of human blood flow, vovine blood flow across each was examined. Microaggregate counts and removal rate were also studies. As to platelets, erythrocytes and leucocytes, counts and residual rate were measured. In vovine blood, percentage of transist of RBC, WBC, Platelet, Microaggregates (10-20μ) and (larger than 20μ) were 97.5, 92.6, 93.6, 57.3, 78.4% in NS and 99.3, 98.1, 86.5, 62.1, 76.4 in Swank. In human blood, tese values were 97.8, 79.2, 75.7, 77.2, 96.4 in NS and 98.4, 80.7, 68.2, 63.1, 94.8% in Swank.

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Blood viscosity increase by swelling of red cells. Otherweise decrease ATP and ADP in the red cells of the severe patient. There controll ion of out and inside of cells for Na⁺-K⁺ ATPase. In future circulatoric insufficiency appears because of hyper viscosity of blood, swelling of red cells due to colapse of Na⁺-K⁺ ATPase system.

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The feasibility and anticoagulability of continuous arterial pH and Paco₂ monitoring were studied in mongrel dogs. Metal oxide semiconductor (MOS) type field effect transistor (FET) is applied to ion sensitive sensor by replacing gate metal and gate insulation membrane of the FET to electrolyte and ion sensitive membrane. We have made pH sensor with double layers of Si₃N₄ and SiO₂ which is sensitive to only H⁺ ion. Also Pco₂ sensor is made of this pH sensor. PH and Pco₂ sensor have good sensitivity and stability for a long period, using small amount of heparin.

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The purpose of this study was to evaluate our modified Neville's prosthesis and new model of tracheal prosthesis (Katsura's prosthesis) in dogs. The complications of prosthetic reconstruction of trachea and carina are formation of granulation and prosthetic migration. To prevent these complication, we modified Neville's prosthesis and developed new flexible Katsura's prosthesis. In animal experiments, the prosthesis, wrapped circumferentially by Marlex mesh which was glued partially to it, _could prevent perfectly the comlication of migration. But new model of tracheal prosthesis could not prevent the formation of granulation at the distal end of anastomosis.

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We have proposed that the microdomain structure of the polymer surface, constructed by hydrophilic and hydrophobic chains, is most important parameter to design good antithrombogenic polymers. In this paper, the morphological and dimentional effects of microdomain structures on the mode of interaction between amphiphilic block copolymers and platelets were studied by the microsphere column method. It was found that the microdomain structures showed the ability to prevent deformation and release reaction of adhered platelets.

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Adhesion behavior of rat mesenteric lymphnode lymphocyte on various polymer surfaces was kinetically studied by using column method. Polystyrene/polyamine comb-type copolymer (SA copolymer) surfaces having microphase separated structure was found to exhibit a unique adhesion behavior toward lymphnode lymphocytes: (i) the adhesion of lymphocyte was segnificantly suppressed on the surfaces of SA copolymer, and (ii) the surfaces of SA copolymer were able to differentiate B lymphocyte from T lymphocyte in terms of adhesivity.

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Effect of crystallinity of polyamides and poly esters on adhesion and detachment of granulocytes and lymphocytes in terms of the separation of granulocytes from whole blood. Adhesion and recovery of leukocytes on these polymer surfaces was evaluated by Microsphere column method. Among leukocyte populations, granulocytes selectively adhered on the polyamide surfaces. Recovery of granulocytes adhered on polymer surfaces was found to correlate with crystallinity of polymers. These results suggested the distribution of microdomains (crystalline-amorphous) plays an important role in reversible adhesion of granulocytes.

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As slow released anticancer drug a needle 5Fu-PGA and MMC-PGA were prepared. High polymerized PGA (hi PGA) and low polymerized PGA (low PGA) were made. 5Fu-hi PGA had slower release rate of drug (5Fu) than 5Fu-low. PGA. And the 5Fu-PGA needle of low concentration of drug had slower release rate of drug. AH130 (1×10⁷/0.1ml) was innoculated into the subcutaneous tissue of male Donryu rate of 5 weeks old. 7 days after, we buried 30% 5Fu-hi PGA needles, 1.5mm in diameter and 1cm in length, into the tumor. Then this 5Fu-PGA needle was markedly effective against AH130. This 5Fu-PGA needle is recommended in order to achieve prolongation of life for inoperable patients.

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The Glutaraldehyde preserved porcine pericardium (Stabilized Porcine Pericardium: SPP). was developed by Rygg I. H. et al and introduced into clinical field. Between May 1978 and June 1982, we used SPP in 53 cases. There were 45 cases of congenital heart disease, such as 24 cases of Tetrallogy of Fallot, 9 cases of ventricular septal defect and so on, Other 8 cases were acquired heart disease. 7 cases, lost at operation, were due to LOS, bleeding and others. We examined 46 alive cases. The post operative observation period was between 5 months and 50 months. In 3 cases, complications were found, But in other cases. no specific complications were seen. Further obeservation is needed.

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By our newly developed cell toxicity test, it was found that the plasticizer of PVC (DEHP) significantly inhibited the cell growth and that glow discharge treatment which prevents the migration of DEHP markedly decreased the cell toxicity of the plasticized PVC.

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Among 28 consecutive patients with tricuspid valve replacement by using starr-Edwards 6520 disc prosthesis, 17 discharged patients were investigated about late complication. The actuarial survival rate of 8 years after surgery was 80% for discharged patients which seems to be a very satisfactory results. Major episodes of the thromboembolism both of the systemic and pulmonary were not observed. Hemodynamic study revealed that the patients who underwent MVR+TVR showed only a slight increase in cardiac output and remarkable increases in the mean right pressure during excercise in comparison with the patients who underwent MVR alone. The study of UCG showed that the movement of the mitral and tricuspid disc prosthesis was satisfactory. Therefore it was supposed that functional tricuspid stenosis occured during excercise in there patients.

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Eighty-two consecutive patients undergoing valve replacement with 96 SJM prostheses have been studied. Eighty-five % of cases were in class III or Win NYHA functional classification. Hospital death of nine cases was encountered with fatal complications of perioperative infarction, low-output syndrome, acute renal failure, and multiple-organ failure. Thromboembolism was observed in four cases with the incidence of 4.14/100 patient-years. There were no cases of mechanical failure. Heaolysis of subclinical level was observed more prominently than in the previous cases with biological valves. This clinical experience indicates that SJM prosthesis offers a viable alternative with the benefits of cental flow, low profile, and less dysfunction.

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Jude Medical valve. The SJM valve has radiopaque leaflets seen by cinefluoroscopy. Both leaflets were seen throughout a cardiac cycle with x-ray beam positioned nearly parallel to the sewing ring, which allowed plane visualization of the leaflets instead of line visualization. Asynchronous closure or early semiclosure seen in some cases, however, did not influence hemodynamic performance.

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Twenty-two patients with a SJM mitral/aortic valve replacement have been studied about 13 months after operation. The data were compared with the results of 12 patients with a B-S valve. In both groups, subjective and haemodynamic improvement were excellent and the calculated effective orifices were no significant differences. But in small annulus diameters under 23mm, the average systolic pressure gradient was over 20mmHg at rest, and over 50mmHg during bicycle exercise in both groups. In SJM groups, high LDH level and diminished haptoglobinemia were more frequently observed.

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Mechanical functions of valvular prosthesis was studied immediately after surgery. LV function (LVDd, EF, and mVcf) was estimated by UCTG 2 weeks and 6 months after valvular replacement. All these factors of AR and MS patients concentrated to the normal value area 6 months after operation. This tendency was not to be ascertained about MR patients.

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We investigated platelet function and blood coagulability under the administration of antiplatelet drugs (Dypiridamole, Ticlopidine), and examined how is the better method of antithrombogenic therapy at early period after operation. Both PT and platelet aggregation were already fairly recovered at 3 days after surgery, and then showed the significant increase. Therefor antithrombogenic therapy by anti-platelet drug should be started as soon as possible after operation.

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This clinical study compares the effects of pulsatile flow (N=17) with nonpulsatile flow (N=13) in 30 patients with an ejection fraction of 0.4 or less. Peripheral circulation (urine output, peripheral body temperature) and myocardial metabolism (O₂ extraction, excess lactate and Redox potential) of pulsatile group were significantly more benefical than nonpulsatile group.

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It has been already recognized by many investigators that the pulsatile flow in extracorporeal circulation is very physiologic and effective than the non-pulsatile flow for open heart surgery Experiences with surgical treatment of descending aortic aneurysm with the aid of pulsatile femoro-femoral partial perfusion were reported. Function of the brain, kidney and peripheral circulation was safely protected and stable circulatory atate was maintained during aortic cross-clamping. The pulsatile flaw can get little derrangement for peripheral circulation, can hold in good condition the blood pressure, the peripheral vascular resistance and the ultrasonic flow curve findings during extracorporeal circulation and can get effectiveness for renal circulation. It can be concluded that extracorporeal circulation under pulsatile flow is more beneficial that those of roller pump during clinical extracorporeal circulation.

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Hemodynamic effectiveness of intra-aortic balloon pumping (IABP) and pulmonary artery balloon pumping (PABP) was evaluated against right ventricular infarction with acute right ventricular failure in swine. Hemodynamic changes in IABP alone was not satisfactory, but PABP revealed its usefulness for right heart failure. Moreover, combination method with IABP and PABP showed much usefulness in many hemodynamic parameters. The origin of its usefulness was thought to be due to diastolic augmentation of IABP and right ventricular systolic unloading of PABP.

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In the clinical, especially in cardiovascular surgery, the extracorporeal circulation plays a nery important part. We need longer and safer circulation, but it is not so easy. Under extracorporeal circulation, we use some markers to make a comfortable hemodynamic state. Contral venous pressure, arterial pressure and urine output are used as markers. So we devised a new circulation system. Markers are put in to system and the system controls itself and makes new levels of markers. Markers levels are kept at stational level automatically. We chose the central veuous pressure as a chief marker. In experimental study, we recognized the expected function of this. It'll be introduced into clinical field in the near future. We named this system. APLEC(Auto matic Pressure Limited extracorporeal Circulation System)

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The purpose of research is to develop an advanced extracorporeal circulation(ECC) system for an infant with automatically controlled blood perfusion. Both of arterial infusion and venous withdrawal are under control of micro-computers throughout ECC. Arterial infusion with either pulsatile or nonpulsatile flow mode is controlled to maintain arterial pressure and cardiac output within an optimum range, whereas venous withdrawal is controlled to regulate CVP and blood reservoir level within a desired range. 25 experiments of dogs and rabbits were performed with 22 successful weavings.

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A recommended procedure was obtained in this report for measuring in vitro solute clearance (C_L) of hemodialyzers. Fundamental experiments on the influence of temparature on C_L were performed with Toray B1-200. Performance estimation of 14 modules was carried out under the fixed conditions to obtain the values of C_L and overall mass transfer coefficient (K) for urea, creat. and VBl These data ere influenced by the valiables associated with module design. The effect of channeling especially in dialysate flow was found to be an important factor in performance estimation of hemod ialyzers.

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By adding urea nitrogen, creatinine, saline to blood of nomal human volunteers, however, it is possible to assimulate clinical uremic states under experimental conditions and so compare the effectiveness and efficiency of various dialyzer. The clearance of BUN and creatinine were measured and U. F. R. P were examined at T. M. P 0/100/200mmHg each and blood flow 100/150/200ml/min each, hematocrit 20/25/30% each, BUN 100mg/dl, serum creatinine 12mg/100ml. Our experimental results were very close to clinical results. We evaluated various dialyzer using our method and have been choosing the best dialyzer for each patient with chronic renal failure. We concluded that our method was a good evaluation method of dialyzers and was abe to be acceptable in clinic.

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This report describes the quantitative analysis for the change of flux during hemofiltration (HF). IN HF, Alubumine, Globurin, Fibrinogen and RBC will reduce water flux, because these substances accumulate on the membrane surface to block the pores of the membrane. One component solution of Inulin, NaCl, Cytochrome C, Myoglobin, Albumin, Fibrinogen were filtrated by Toray Bl-L. The results adjusted by using Harmans-Bredee-Grace equations. These H-B-G equations are suited for the examination of the change of water flux with time. These equations can predict the water flux at any time under constant pressure and flow conditions.

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Membrane structure and protein layer found upon membrane have a strong effect on module performance for hemofiltration. The protein layer is a rate determing step in ultrafiltration so that it may determine UFR. The bovine in vitro data observed with Toray Bl-L gave a good relationship between shear rate and UFR. The experiments carried out with the filter, which was constructed in our laboratory, showed an increase of UFR near the inlet. These data suggests that a filter must be constructed so as to keep a high shear rate which inhibits the formation of protein layer.

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The new modified HFK has three pairs of dialysate connectors on the side of HFK housing symmetrically so that we are able to change its effective surface area and dialysate flow length easily and repidly. In vitro studies were made with available nine ways of dialysate flow by utilizing two dialysate connectors (others should be closed with caps). VB 12 and Chrolide clearance were measured and compared respectively. Conclusion: In practise, modified HFK should have one dialysate inlet on the lower part of housing and three outlets on the opposite side so that the values of clearance are controlled easily.

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Bicarbonate dialysate is useful and popular as buffer solusion of dialysis. In order to care metablic alkalosis or severe metabolic acidosis, we have exprienced bicarbonate gradient dialysis in low or high bicarbonate concentration, at the beginning of dialysis and in regular bicarbonate concentration later.

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For the evaluation of plasma separators, the clearance, Ks, can be regarded as a measure of efficiency and expressed as: Ks=Qf·Sc where Qf is the plasma filtration rate, and Sc is the sieving coefficient. With this parameter, newly developed POLYETHYLENE hollow fiber plasma separator has been evaluated and shown to be one of the best filters.

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Our new plasma separator (PLASMAX) is a hollow fiber type separator using polymethylmethacrylate (PMMA). Our new plasma separator has been studied experimentally in 10 dogs. The dog was heparinized with 200u/kg of heparin, the extracorporeal perfusion through the PLASMAX was continued for 18min. at the flow rate of 60ml/min. The 200ml plasma was obtained from the blood by filtration without detectable damage to the cellular components of the blood. Duaring the initial stage of perfusion, transient drops of platelet and white cell counts were observed. After the perfusion. the plasma proteins decreased by 28* in mean value, but recovered 2 days after. Sieving coefficients of the proteins of the plasma using PLASMAX was probably simillar to those obtained by centrifuge.

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56-year-old male with malignant RA was treated by 6 plasma exchanges with prediluted plasmapheresis using the ASAHi PFO-02. Bloodaccess was gained from both cephalic vein of forearms for afferent and efferent line. The blood of flowrate 70ml/min was diluted by Hartman's solution, which was infused with flowrate 30ml/min by roller pump through the afferent line. As a result of dilution, blood flow for afferent line increased up to 100ml/min. After plasma exchange the titers of RAHA and ANA decreased. The sieving coefficients and filtration efficient of IgM did not tended to decrease with at least over 1 hour of perfusion.

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The main objectives of this study were standardization of the evaluation method of cryofiltration and assessment of applicability of thee process to various disease states in cryofiltration systems. In vitro filtration tests were carried out with normal and pathologic plasma at varying temperatures. The results of these experiments indicate that the filtration process is related to temperature and plasma constituents as demonstrated by variation with disease state.

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