In 4 children (2.4-10.9 y.o) with mitral valve regurgitation, prosthetic valve replacement was done using warm heart surgery. Three of them had previously received 1-3 times valve repair operations and the other one was accompanied by endocarditis. The condition of 3 children were in NYHA grade 4 and received dopamine preoperatively. At the esophageal temperature of 34 degree, aorta was cross clamped for 79-216min. with continuous coronary perfusion of 3ml/kg/min, however, no child showed postoperative low output syndrome, and the maximum use of dopamine was 2-6μg/kg/min and the CK-MB at 1POD was within the normal range in all cases. Warm heart surgery showed better myocardial protection for pediatric mitral valve replacement.

In order to reduce the blood transfusion volume in open heart surgery, the new blood autotransfusion technique using cardiotomy reservoir unit BCR 3538, which was configured to serve also as a receptacle for postoperative mediastrinal drainage, was introduced. To investigate the utility and the problem in this system, every clotting factor, platelets' function and the extent of the hemolysis were measured serially both in patients' arterial blood and the shed mediastinal blood. The bank blood transfusion was significantly reduced to 250ml±330ml by this system compared to the 1080ml±820ml in the cases of usual system (p<0.01). Every clotting factor recovered well in patients' arterial blood after cardiopulmonary bypass (CPB). In the reservoir blood, the clotting factor IX, XI, XII were extremely suppressed at 1h CPB, and 3h after the CPB, every clotting factor except fibrinogen (42±28mg/dl) showed the quite higher activity, such as factor VIII 400%, IX 365%, XI 72%, XII 267%. Namely, the anticoagulability of the reservoir blood was maintained due to the effect of the residual heparin at 1h after the CPB, and due to the contact defibrinogation of the shed mediastinal blood at 3h after CPB. The free hemoglobin level was extremely high on the reservoir blood at 3h after CPB. In 6 cases, the autologous blood retransfusion was abandoned by clott formation in the unit because of the contamination of the intraoperatively used fibrin glue. From this study, the autologous blood transfusion using cardiotomy reservoir BCR 3538 was useful not only for saving the transfusion of the bank blood but also the hemostasis after CPB. But to reduce the hemolysis in this system, and to establish the safety against the other clotting material such as fibrin glue were the problems which should be resolved in future. I appreciate the kind support of Alexander von Humboldt Foundation for this study.

Three cases of LMCAP for the isolated LMCA stenosis were presentd. In two cases of the proximal LMCA stenosis, the connective tissue between the ascending aorta and the main pulmonary artery was prepared to detect the LMCA. From the left lateral wall of the ascending aorta to the anterior wall of the LMCA over the stenotic lesion was excised and the saphenous vein patch was sutured (anterior approach). In the third case, because the stenosis was locarized at the distal LMCA, the patch angioplasty using the saphenous vein was performed by direct opening of the distal LMCA accessed from the left lateral side of the main pulmonary artery without aortotomy (lateral approach). Ultrasonic cuser was quite useful to isolate the LMCA. LA-LV vent was indispensable to obtain the non-blood clean operation field. All three cases showed the successful enlargement of LMCA at the postopeorative coronary angiography.