A jacket type artificial kidney, which provides all necessary for hemodialysis such as dialyzer, blood pump, dialysate delivery system containing absorbents, monitors and energy source, and can be worn just like a jacket, has been devised.
Rough estimation from a stand point of solutes removal in in vitro experiment shows that a patient can move around for about 30 minutes only with this apparatus.

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To reduce time necessary for removal of residual HCHO or E. O. from the conventional artificial kidney (AK) s before their use, a novel HF type AK, TF-15, sterilized by steam autoclaving and containing distilled water, was developed. This AK has been found to demonstrate satisfactory performance and biological safety in vitro as well as in clinical trials comparable to the conventional AK's. It is also confirmed that the novel AK requires less time for its preparation, can be used without any side effect s due to sterilizing agents and is useful for E. O. or HCHO sensitive patients.

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So we made a new plasma separating artificial kidney, which is composed of ultrafilter and adsorption column. As a plasma separator, a nucleopore membrane filter was used and polyacrylnitrile membrane was used as an ultrafilter. The adsorption and reactive parts were composed of adsorbent and cation exchange. Massive ultrafiltration end transfusion were used for electrolyte correction and removing urea nitrogen, so this method was proved available as a dialysate free artificial kidney in animal experiments.

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A new HFAK which has completely different membrane material, Ethylene-Vinylalcahol copolymer membrane, from presently exsisting cellulosic was evaluated. In vitro examination evidenced that UFR was 3 times larger, CVB12 2 times larger, Cinulin 3 times larger, and Curea and Ccr at least comparable to that of conventional cellulosic HFAK.
In clinical assessment, UFR reduced to half of in vitro, but Curea, Ccr and Cu. a. were almost similar to in vitro.

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The Carbon Fiber Mixed Dialyser (CFMD) by our development is of plate type, comprising four laywrs with an area of 0.72m². This apparatus consists of corrugated Carbon fibers (K-Filter), which are incorporated in dialysate laters. The following characteristics were revealed in in in-vitro experiments 1. The K-Filter acts also as the support.
2. It's excellent in creatinine and uricacid clearances.
3. It is expected also to have dialysatepurifying action (e. g elimination of bacteria and the like)
Further hopes can be placed on it as a new dialyser in combination with suitable absorbent.

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A new system to be used in ECUM was produced. This unit measures 513mm×355mm×323mm and incorporates a vacuum pomp and water tank of which temperature is controlled through a temperature controlling circuit. Negative pressure is controlled in the range of 0-450mmHg, and blood temperature in the range of 36-38°C by means of a heat exchanger. The unit is equipped with a blood pressure monitor, vacuum gauge and temperature monitor. The blood tube (3.4mm in diameter and 3M in length) is pre-coiled and disposable. The heat exchanger is used by putting the coiled blood tube into a plastic case.
The unit is easily prepared for use and is handled with ease. Efficacy of the fluid removal is excellent.

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We have developed an automatic UF control system which makes it possible to regulate UFR easily and to pre-set the total OF precisely. This system consists of a chamber divided into two parts by a flexible silicon diaphragm, a dialyzer and a negative pump. They make up the closed circuit, accordingly, a amount of fresh dialsyate drawn from one side of a chamber should be equal to that of used dialysate filled the other side up from the dialyzer. Then, the fluid extracted from this closed circuit by the UF metering pump will be replenished from the blood compartment of the dialyzer. Combination of two chmbers which operate alternately, one being at dialysis position while the other is at dialysate renewal position, makes continious dialysis possible. Clinically more than 150 dialysis treatments have been tried with this apparatus in combination with 11 different types of dialyzers. This system was independendent from venous pressure and blood flow rate changes. The discrepancy between pre-set total UF and patient weight loss was within the measuring limits. Its standard deviation was 0.15 Kg..

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We have developed an automatic hemofiltration system in order to operate easily and to equalize UFR with substitution rate precisely. The system consists of two 2-chamber roller pumps, a level controller and a filter. 2-chamber roller pump (1) has two functions: delivering blood to the filter and producing negative pressure to facilitate UFR. Ultrafiltrated was transported into a level controller which regulated performance of two chamber roller pump (2). Two chamber roller pump (2) was for delivering substitution fluid into the venous line and for draining ultrafiltrate at same rate.
An extra ultrafiltrate was drained via the level controller by flow meter.
PMMA hollow fiber dialyzer (Toray A-1) was used as a filter. Blood flow and ultrafiltration rate were 50-300ml/min and 10-110ml/min, respectively. Discrepancy between graduated total UF except an extra UF and total substituion fluid was less than 2% when a venous pressure below 150mmHg. In vivo, sieving coefficient for urea, creatinine, inorganic phosphate and uric acid were 1.08±0.26mg/dl, 1.10±0.22mg/dl, 1.09±0.28mg/dl, 0.91±0.20mg/dl, respectively. Plasma clearance for 99.96±14.5ml/min, 98.48±13.54ml/min, 96.21±15.39ml/min, 79.40±14.46ml/min, respectively.
An exchange of body fluid between 18 and 20L was sufficient to remove metabolic wastes with regard to urea and creatinine.
Two patients were treated with only hemofiltration for nine months. Other two patients were treated with hemofiltration and hemodialysis alternately.
Their clinical course were not eventful. Disequilibrium syndrome, such as hypotension, crump, nausea and vomiting scaresely occurred during hemofiltration. Plasma triglyceride and cholesterol levels significantly decreased inspite of moderate increases in BUN and serum creatinine, after three to nine months hemofiltration period. Hemofiltration therapy seems to have some superior effects to regular hemodialysis therapy.

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Ultrafiltration characteristics of the PMMA-HFAK were measured in the in vitro studies. Two regions were found in the plots of ultrafiltration rate (UFR) versus transmembrane pressure (TMP). In the first region UFR linearly depends on TMP, and in the second region UFR reaches a plateau. The plateau level increases according to the increase of blood flow rate. This characteristic is elucidated by the theory for ultrafiltration of protein solutions. The quantity of proteins deposited on the PMMA membranes are slightly less than that on cellulosic membranes.
According to these results, we can expect to use PMMA-HFAK as the device for new therapies, for example, hemofiltration and hemodiafiltration.

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It has been known that hemofiltration is more phisiological than other available procedure for reduction of uremic products.
Present in vitro study was undertaken to qualitatively evaluate hemofiltration method, and to clarify qualitative difference between predilution and postdilution method.
Solutes in ultrafiltrated sera were divided by molecular filtration method with Sephadex G15. Amicon Diaflo Membrane PM10 (10, 000), PM30 (30, 000) and XM50 (50, 000) was used to ultrafiltrate uremic diluted or nondiluted sera.
Results were as follows;
1. Chromatogram pattern of the ultrafiltrated sera did not changed according to the dilution of sera.
2. If molecular cut-off point of ultrafilter increased, a new peak was showned on the chromatogram.
3. However, such cases belonged to the minority group.

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Two fluid regulatory apparatus namely equalizer and UFR controller have been developed to carry out hemofiltration and hemodiafiltration. Filters used were Toray Filtryzer. Substitution fluid which contains lactate in addition to other solutes, was introduced through venous line.
Equalizer was used for hemofiltration and UFR controller was combined to the former in case of hemodiafiltration. Both of them regulate input and output of the fluid within acceptable limit.
Two patients treated with hemofiltration and 3 patients with hemodiafiltration. The latter procedure could shorten duration of the treatment to 4 hours without any untoward effects.

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20 patients were treated by 150l dialysate added with essential amino acids for more than 1 month. This resulted in high hematocrit level, serum albumin and serum iron of these patients. And nitrogen balance was slightly positive.
This treatment can not be normalized aminogram. The results indicate that dialysate added with essenial aminoacids was effective to maintain positive nitrogen balance and prevent wasting syndrom in chronic hemodialysis patients.

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We developed the central supply system for the dialysate with bicarbonate as a buffer. Three main problems occured to make bicarbonate dialysate as follows;
1) precipitation of carbonates.
2) control of dialysate pH.
3) corrosion of materials used for the device.
Precipitation of carbonates and control of dialysate pH were solved by the addition of lactic acid or co₂ bubbling and indirect heating of dialysate. Metals used for the device were corroded in the presence of bicarbonate. We have tried a sus-304 and sus-316 stainless steel for twenty weeks. Sus-304 was corroded in this period. Sus-316 had more resistant to the corrosion than sus-304. In order to prevent a corrosion, a ceramics and titanium seem to be suitable for the bicarbonate dialysate-central supply system.

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Changes of dialysis efficiency and gas diffusion ability through membrane with degasser using compact dialyser—especially parallel flow type— was studied on 65 times hemodialysis.
With degasser experiments, mean degassing rate of dialysate P_O2 was 35% and decreases of ΔP_D were remarkable in more compact dialyser (ex. Hemoclear, and T-CP) which had high ΔP_D. Dialysate P_O2 was unchanged with or without degasser.
UN dialysance increased in 5-10% on each dialyser with degasser.
No remarkable decreases of blood P_O2 and P_CO2 during hemodialysis with degasser were seen.
Efficiency of dialysis with degasser was discussed and emphasized in this article.

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The bone mineral content was measured 2 and 6cm each, proximal to the dorsal distal edge of the ulna, applying the method described by Nucler et al and Bone Mineral Detector. The error in a coefficient of variation was 3.4% on the distal measuring site including the irregularly shaped epiphyse of the two bone and considerably less of 1.4% on the proximal site.
Although they have been dialysed using 7mg/dl of calcium contents dialysate, the Bone Mineral Content of fore arm in long term hemodialysed patients have been decreasing year by year.

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Components of sorbent column of TM 101 are 500g of activated charcol and 200g of alumina.
The reduction of Ca in dialysate during dialysis was found to be significantly greater in the system with sorbent column than in the system without sorbent column.
This might have been either Ca transfer from the dialysate to the blood or considerable Ca adsorption to the sorbent column.Further studies were carried out to clarify this phenomenon.
As a result, it was proved that 800-900mg of Ca is adsorbed to the sorbent column through the measurement of reduction of Ca, Supplement of Ca acetate and change in serum Ca and proper supplement dosis of Ca was determined.

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Function in 31 types of dialyser in vivo was evaluated from the clearance studies of urea, creatinine, uric acid and phosphate and the rate of ultrafiltration (UFR) under the condition of Q_B200ml/min, Q_D500ml/min and 250mmHg in transmembrane pressure. The dialyser with large surface area (1.8-2.5m²) has higher clearance of small molecules than the dialyser with standard surface area.Correlation between clearance of small molecules and UFR was high in dialyser with cuprophane membrane, but not always found in dialyser with other membrane material.
These results is considered to be dependent of membrane material and membrane thickness.

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The resistances for the urea transfer in the coil-type, plate-type, and the hollow fiber-type hemodialyzers were split into the resistances of the blood phase, dialyzing membrane, and the dialysate phase. Empirical equations forthe blood phase and the dialysate phase mass transfer coefficients containing the blood and dialysate flow rates were obtained. The blood phase mass transfer coefficient was further correlated with the hematocrit. The results indicate that the blood phase resistance is more than half of the overall resistance in any of the hemodialyzers studied.

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Coil dialyser (RSP Type) has been widely used in the dialysis centers. It has a dialysate tank named canister, in which the partial dialysate is recirculated with a high flow rate. The phemomena within the appratus are made quite complex with the recirculation of the dialysate and the existence of the canister. The mass transfer mechanism of the coil dialyser was studied in order to evaluate its performance. The relation between clinical expression such as clearance or dialysance and technical expression was also made clear, and the dynamic characteristic in the appratus was examined.

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In this study a new parameter CL/B. W. was considered in analysing the artificial kidney system (A. K. S.). Using this parameter, the transfer phemomena of thre three kinds of solute in A. K. S. was examined by 2-pool and new model.
Those were urea, a solute stored in tissue like creatinine and a solute combined with some kind of protein.
The urea transfer property under any values of clearance in A. K. S. became equal if CL/B. W. was decided to be constant. The transfer amount of the solute that has a property of storage in tissue or protein binding was decreased inversely propotional to the quantity of storage in tissue or binding to prtein.

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Rapid decrease of toxins by the direct hemoperfusion may necessitate the consideration of the mass transfer mechanism within the body. The mass transfer model used in this study has been shown to be suitable for thr performance evaluation of the direct HP.and the evaluation of relation between amount of adsorbent and clearance. When the exit concentration of a solute remains zero in the adsorber, clearance is equal to the blood flow rate. It was also found that the new 2-pool model using a new parameter MKfAv fully described the solute transfer phenomena within the body of the reanal failure dogs.

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We obtained 14 patients who had sustained acute renal failure due to the open cardiac surgery from jan. 1975 to dec. 1976. The morbidity was 3.2% of 474 operated patients and the overall mortality was 29%. In those patients we performed the hemodialysis that had not only A-V flow but also V-V flow and V-A flow in the occasion with circulation disorder.

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In our department, 63patients of acute renal failure have been treated by hemo or peritoneal dialysis. Total survival rate was 52.4% But postoperative acute renal failure, especially cardiovascular and hepatobiliary surgical renal failure was very bad. The survival rate of the 11 patients whose age were over 65-years-old was 27.3%.
V-V shunt by Shaldon's catheter is most suitable for blood access of acute renal failure because operation procedure is very easy.
The record of plethysmogram during hemodialysis is fit for monitoring of patients, particularly dilated wave and cardiac plateau wave suggest circulatory failure such as hypotension or arrhythmia.

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Hemodynamic evaluation of different states of water balance in dialytic patients was made, especially during hemodialysis. C.O., PA, and ET/PEP were used as its parameters Consequently, C.O. change during procedure was classified into two different patterns. Hypervolemic patients showed its change such as Type A C.O. pattern (Y=ax²+bX+c, a<o), however, normo- and hypovolemic, Type B C.O. Pattern (Y=aX+b, a<o). PA change during it decreased linearly despite of different C.O. patterns. Generally. ET/PEP and C.O. correlate well. ET/EP was, at least, clinically useful as semiquantitative value in Type B C.O. pattern, however, in hypervolemic remained further investigations.

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Motor and sensory nerve conduction velocities in thrice weekly hemodialysis patients (N=33) were compared with those of twice weekly hemodialysis patients (N=22).
Motor nerve conduction velocity (MCV) was measured at the site of median nerve, ulnar nerve and tibial nerve.
Sensory nerve conduction velocity (SCV) was measured at the site of median nerve, ulnar nerve and sural nerve.
The following conclusions were obtained.
1. There was no statistical difference among both groups on the mean of MCV and SCV at any sites.
2. There was no significant difference in incidence of subclinical and clinical neuropathy among both groups.
abnormal (delayed) MCV
thrice weekly group 24.2%
twice weekly group 36.4%
abnormal (delayed) SCV
thrice weekly group 72.7%
twice weekly group 59.1%
normal NCV (both MCV and SCV)
thrice weekly group 7 cases (21.2%)
twice weekly group 8 cases (36.4%)

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Recently in our dialysis center, we have been treatingpatients with various complications or troubles. Therefore we have to apply them to prescription dialysis. We have developed dialysate prescription system (DPS) in dialysate central supply system for purpose of easy preparation of dialysate content one by one. We used it to prevent disequibrium syndrome in a variety of dialysate concentration of Na⁺, K⁺, Ca⁺⁺ or HcO-₃ and had satisfactory results. We think this system will be useful clinically

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Several surgical techniques for mitral regurgitation were progressively abondoned mainly because of the difficulty to achieve a regular and predictable result and high incidence of recurrent regurgitation. But the valve prosthesis still involve thrombotic problem and a persistent need of anticoagulation.
The recent and considerable progress in mitral valve surgery has been incentive for cardiac surgeon to improve our knowledge of the details of mitral valve and to perfect our surgical techniques to repair and reconstruct the mitral valve apparatus if possible. Progress in extracorporeal circulation and myocardial protection allows us to perform more sophisticated technique
The purpose of this paper is to state the Stanard principles and guidelines for reconstructive surgery of mitral regurgitation and its superiority in postoperative cardiac function rather than mitral valve replacement.

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From April 1973 to October 1977, tricuspid regurgitation was encountered in 17 (19%) patients of a total of 88 patients undergoing valve surgery. During this time, tricuspid annuloplasty with Carpentier's prosthetic ring was performed in 12 patients.
Hospital deaths occured in 2 patients due to left ventricular rupture (1) and low output syndrome (1). Death has never been related to tricuspid valve malfunction.
In a follow-up period of 6 months to 32 months, there have been no late deaths, no thromboembolic complications, no recurrent insufficiency and no permanent AV blocks. Decreasing of heart size and improvement of general condition were recognized in all patients.
Tricuspid insufficiency can be managed by this technique.

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During the past 17 months from June 1976, aortic and mitral valves have been replaced with a Lillehei-Kaster pivoting disc prosthesis.
The hospital mortality was 28.5%. All of the patients leaving the hospital showed definite improvement and were in N. Y. H. A. functional classes I and II
The hemodynamic function of the prosthesis was assessed intraoperatively.
The average pressure gradients across the prosthesis were minimal (4.32mmHg in AVR and 4.68mmHg in MVR) and the average calculated valve areas were satisfactory (1.86cm² in AVR and 2.75cm² in MVR) As the number of the operation is still small and the follow-up period is too short, we will continue to use this prosthesis to reach final conclusions.

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Although, various holders for prosthetic valve of rigid type have been developed. Here cannot be found any suitable holder for bioprothesis.
Recently we made a specially designed valve holder for bioprothesis, that has two components, i. e. six holding arms their controlling cylinder. Fig. 1 This holder may be avairable for all positions of cardiac valve and any types of stented leaflet valves.

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The physical changes of porcine valves treated by 0.2% Glutaraldehyde solution (OA), 0.65% GA, and 1.3% Dialdehyde starch solution (DAS) were evaluated. The tensile strength test and flexural fatigue test showed that porcine aortic valves treated by 0.2% GA and by 1.3% DAS appeared sufficient strength. Histologically, the valve treated by 0.65% GA showed relatively low grade antigenicity, but there is no obvious difference between the orthers. By grafting conduits with a valve between canine's right ventricule and main pulmonary artery, fresh or treated by 4% Formaldehyde solution tissus valves showed almost thrombus formation and leaflet's atrophy, but porcine aortic or pulmonary valves treated by 1% GA appeared to be normal pulmonic pressure, no pressure gradient, leaflet's pliability and reduction of the host reaction.

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The patient was 27 year-old female. At 23 year-old, under the diagnosis of endocardial cushion defect (complete form, type III), operation was performed and resulted complete atrioventricular block. So the patient was implanted a permanent pacemaker with myocardial electrodes. At 26 year-old, when the cardiac function of the patient was evaluated to be within NYHA grade II, postoperative cardiac catheterization was performed, and it revealed small residual left to right shunt and mitral regurgitation. Exercise test revealed that cardiac output did not increase properly with usual pacing rate, but it increased easily by increasing the pacing rate. When the patient was made a diagnosis of pregnancy at 27 year-old, the previous pacemaker was removed and a rate programable pacemaker was implanted.
All through the procedure of pregnancy, delivery and puerperium, the patient was controlled well by the rate programable pacemaker.
programable pacemaker implantation has much advantage in such a case of pregnancy, the hemodinamic condition of that is changing for long term.

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Since 1970 fifty-five patients have undergone implantation of cardiac pacemakers. Of these, 13 percent underwent the implantation for the last two and a half years. The age of the patients ranged from 5 to 89 years and was 58.1 years on the average. Twenty-five were male and 30 female. Of 55 patients, 8 died after implantation (mortality rate 14.5%). The mean age of the dead patients was 69.5 years and was much higher than that of the alive patients.
Except 8 dead patients and 2 other patients who changed their residences, 45 patients were analyzed in regard with rehabilitation after implantation. Improvement was obtained in 42 patients from NYHA functional class II-IV to I or II and 3 patients from IV to III. However, the rate of rehabilitation was rather unsatis-factory in consideration of degree of improvement and decreased in accordance with growth of age. No patients who had been engaged in heavy works preoperatively returned to the same occupations and were obliged to change their jobs or retired. As their factors there are age, sex and works.

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Clinical and hemodynamic studies were carried out on the 9 patients with atrial pacemakers for sick sinus syndrome
In 3 of them, atrial pacing had to be discontinued because of increased threshold, apperance of A-V block and pressure necrosis at the site of pulse generator. In the remaining 6 patients, two cases developed transient atrial fibrillation which subsided by administration of digitalis or quinidine.
The hemodynamic superiority of atrial pacing was demonstrated by the increase in cardiac output by 20% comparing with that of ventricular pacing. The significance of the atrial contribution was more evident after exercise.

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This study is based on clinical experience with 193 paced patients. The analysis represents a seven-year study of general follow-up of 292 implanted cardiac pacemakers which represent 4540 pacer-months of experience. There were 74 troubles (38% of paced patients); 20 generator troubles (6.9% of 292 generators); 28 electrodes troubles (12.6% of 223 electrodes, 11.5% of 209 endocardial electrodes, 21.4% of myocardial); 26 surgical complications (8% of 324 procedures). Two Patient died of electrode troubles. Thirteen patients decreased of other diseases during follow-up study.
Our follow-up study revealed that electrode trouble was fatal, so careful manupulation should be taken at the implantation to prevent not only surgical complication, but electrode trouble. Our analysis indicates that testing should be performed weekly for the first month following lead manupulation, thereafter tests should be performed monthly for the first and second pacemaker life.

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The effects of terminating imposed rapid rate driving through an artificial pacemaker were studied in 18 patients with complete A-V block.
Post-drive depression of pacemakers and the resulting deceleration of the heart is observed in almost all cases. Idioventricular pacemakers showed much depression following imposed ventricular drive than did A-V nodal pacemaker. The max. recovery time after drive in H-V block reached 10sec. or more. In some cases entrance and exit block of latent pacemakers were observed. Atropine does not abolish the post-drive depression. From these results it is concluded that, in patients with complete A-V block, frequency-dependent inhibition is important for the analysis of the functional specificity of atrioventricular b-lock, when latent ventricular pacemaker will have to activate the ventricles.

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Temporary inhibition test of implanted pace maker generators with R-wave inhibited demand function have been performed in 25 patients, in whom 15 had A-V block, 8 sick sinus syndrome and 2 other bradycardias. Pacing was interrupted temporarily by the test and followed by ventricular asystole durating over 5 seconds in 9 of 15 patients with A-V block and none of 10 with other disturbances. Significant prolongation of R-R intervals of intrinsic ventricular rate after pacing was observed during temporary inhibition test, which suggested some progrssion of extent of conduction disturbance. In some patients abnormal ST, T or Q waves were found after interruption of pacing. These findings obtained were much more remarkable in A-V block than in others. The high incidence of long durating ventricular asystole especially in the patients with A-V block should be a warning of possible occurrence of Stokes-Aadams attack on the occasion of unexpected interruption of pacing.

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The endocardial potential is important for pacemaker to act normal demand function. We have investigated endocardial ECG in the normal, myocardial infarction, congenital heart disease, complete A-V block and mitral stenosis. There is no statistical differences between complete A-V block and congenital heart disease, mitral stenosis and the nornal. There is statistical difference between complete A-V block and myocardial infarction. The endocardial ECG is usefull in diagnosis of dislocation of electlode, myocardial perforation resulting electlode at bet side.

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During the pacemaker implantation and puls generator replacement, unipolar right ventricular electrograms were recorded from 26 patient (24 at implantation and 6 at puls generator replacement). The mean voltage was 7, 5 7 my in initial implantations. The chronic voltage amplitude is 11 percent lower than that of acute electrogram.
There was a direct correlation between surface area of the electrodes and the Q RS potentials measured. With the present trend toward utilization of small surface area electrodes to reduce pacemaker cell draine, care must be taken to avoid the sensing problems.

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The hemodynamic changes at the time of right or left ventricular pacemaking, through a wide range of pacing rate, were compared in 4patients who long term ventricular pacings have been performed. On the otherhand, the same study was done in 9dogs with left thoracotomy, or with ligation of the left anterior descending coronary artery.
Consequently, cardiac output at the time of the left ventricular pacing revealed higher value than that of the right ventricular pacing in 3patients with congestive heart failure. But no significant differences of cardiac output were observed in lpatient without heart failure, and besides, in all dogs at the each ventricular pacing above described.

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The relationship of the pulmonary arterial systolic, mean and end-diastolic pressure to the mean left atrial pressure was investigated under artificial ventricular pacing in dogs (n=20) with complete A-V block.
The ventricular pacing rate was changed in range from 80 to 200 beats per minute, and the cardiac output, the pulmonary arterial pressure and the mean left atrial pressure were measured.
The relationship of the pulmonary arterial systolic and mean pressure to the mean left atrial pressure did not correlate with a change in the ventricular pacing rate, but the pulmonary arterial end-diastolic pressure correlated with the mean left atrial pressure (r=0.78) in the range from 110 to 200 beats per minute.

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