An easy and practical technique for absorbing water solutions in expanded polytetrafluoroethylene was developed with the aid of a commercial syringe.
The degree of absorption of water solutions increased with the increase of the length of internodal fibrils (pore size) and reached a saturation when the fibril length was over 20μm.
The saturated degree of absorption of heparin solution was much larger than that of water in the same specimen.
When the heparin absorbed specimen was exposed in the running water, the release of heparin was very slow.

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The S. J. M. valve (St. Jude Medical: U. S. A.) is one of new developments, which has been approved for use in Japan since 1978. Compared to other conventional artificial valves, it has many unique features. We used the S. J. M. valve clinically for 120 patients. Operative results and postoperative improvements are reported. Between July 1978 and March 1980, 120 patients had been operated on valve replacement with 132 S. J. M. valves in the first department of Surgery, Tokyo Women's Medical College. The 111 survivors (mortality rate=7.5%) were observed for a total of 1, 617 months (134.8yrs) over a period of 6 to 26 months (mean 13.5 months).
Clinical diagnosis of these patients was variable. In 7 cases aortic valvular disease and in 17 cases mitral valvular disease were isolated. Seventy seven cases had combined valvular disease and in 48 cases of them aortic or mitral lesion was accompanied with tricuspid regurgitation. In 12 cases valve replacement was for the second time. Bentall's operation was done in 3 cases.
Routine anticoagulant treatment by coumadin derivatives was done after the operation in all of the mitral except for one case and almost all of the aortic cases. Thromboembolism occured in five cases (3.7% 100 patients years). In three of them thromboembolism was due to poor anticoagulant treatment. Postoperative improvements were evaluated in 36 cases of single valve replacement cases. After surgery, subjective improvement, according to N. Y. H. A. classification, was two classes in 8 patients, one class in 26 patients and 2 cases remained same. No patients in these group deteriorated. C. T. R. reduced its mean from 62.8% to 56.6%. Average cardiac index increased from 2.5l/min/m² to 3.01/min/m². Pulmonary artery wedge pressure reduced from 20.2mmHg to 11.2mmHg. In 3 aortic and 24 mitral cases, pressure gradients and valve areas were calculated. AVG was 19.7mmHg, AVA was 1.6cm² with 25mm dia. M. V. G. were 8.7mmHg with 25mm dia, 7.0mmHg with 27mm dia, 7.1mmHg with 29mm dia and 4.7mmHg with 31mm dia. M. V. A. were 2.2cm² with 25mm dia, 1.7cm² with 29mm dia, 1.8cm² with 29mm dia and 2.4cm² with 31mm dia.
The cause of five thromboembolisms were considered from poor control of the coagulability in three cases and unknown in two cases. We feel antico agulant treatment is rather necessary postoperatively. Results of postoperative catheterization revealed that function of the S. J. M. valve was about equal with the Björk-Shiley valve and the Lillehei-Kaster valve.

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The adequacy of the surface area of indifferent plate used in analysis pacemaker system was evaluated and it was indicated that it should be more than 6.0 cm2 to obtain accurate stimulation threshold and lead impedance.
In order to achieve permanent pacing with certainty, an indifferent place of enough size must be used though the life of battery may be shortened.

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Rinse of the extracorporeal circulation circuits is employed not only for removal of ethylene oxide gas and examine the circuits itself, but also for washing out fine foreign bodies within the circuits.
This study was undertaken for evaluation of the effectiveness of disposable pre-bypass filter (Harvey H-600) in the clinical use.
Pre-bypass filter was used clinically for 30 patients.
After setting the extracorporeal circulation circuit, rinse of the circuit was performed for 5 minutes using 5% glucose solution by total bypass flow.
Filter was removed from the circuit and examined by the scanning electron microscope.
By these examination, many foreign bodies were observed on the surface of the filter and total foreign body number was calculated as 8, 799±5, 512.
From these data, it is suggested that rinse of the extracorporeal circulation circuit is useful and that employment of this filter is really effective.

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