Left heart bypass was performed with Bio Medicus Co.-made Bio-pump, a representative centrifugal pump. A vinyl chloride tube for the usual cardio-pulmonary bypass not treated with antithrombogenic material. was used in the bypass circuit. In the experiment, the mongreal adult dogs were divided into the systemic heparinized group and non-heparinized group and the bypass was performed for 6 hours. As a result, coagulation and fibrinolysis were more activated in the non-heparinized group than the other group. So, when this method is used clinically, a small quantity of heparin should be administered. Clinically, this approach was used as an adjunct in operation for 7 cases of thoracic aortic aneurysm. During left heart bypass, a small quantity of heparin (0.5-1.0mg/kg) was administered. A rise in FPA and FDP considered attributable to autotransfusion during the operation was noted. Distal perfusion could be performed fully and the amount of bleeding during and after operation was small, but 1 case each of acute renal failure and paraplegia as postoperative complication was encountered. Neither was considered due to left heart bypass; and, changes in respiratory system and hepato-renal function were considered within the tolerable range. These results have led us to believe that left heart bypass using Bio-pump is safe and useful as an adjunct in operation for thoracic aortic aneurysm and should be used positively in the future.

A 63-year-old woman underwent coronary artery bypass grafting and mitral annuloplasty 4 years previously. She was readmitted owing to heart failure. Cardiac catheterization revealed worsened mitral regurgitation, although the internal thoracic artery (ITA) graft had good patency. Reoperation was performed by median resternotomy and continuous retrograde cardioplegia without clamping the ITA graft. The mitral valve had a perforation in the anterior leaflet, and was replaced by a 29mm Carbo-Medicus valve. The patient was discharged with transient myocardial ischemia. Although median resternotomy and continuous retrograde cardioplegia at reoperation provided on excellent view and myocardial protection, myocardial ischemia in the region perfused by the ITA graft may occur when the ITA graft cannot be clamped during continuous retrograde cardioplegia.

A gelatin-sealed knitted Dacron graft which has zero-porosity at implantation and does not require preclotting preparation has been developed. Gelatin-sealed aortic grafts were implanted into 39 patients and vascular surgery reconstruction was performed for thoracic aortic aneurysm (TAA) in 10, abdominal aortic aneurysm (AAA) in 19, and arteriosclerosis obliterans (ASO) and other conditions in 10. A total of 39 bifurcated or straight grafts were inserted. The Gelseal Dacron graft had superior handling characteristics and biocompatibility in comparison to conventional graft. There was no measurable blood loss from the body of the sealed graft at the time of implantation. The gelatin-sealed Dacron graft (n=10) was compared with an Intervascular Micron^® graft (n=10) implanted into the abdominal aorta. No problems were evident with regard to intraoperative bleeding, allogenic and autologous transfusion volume and blood parameters between the two groups. These results suggested that the Gelseal Dacron graft sealed with gelatin was a safe, zero-porosity implantable prosthesis for clinical use.