A 47 year-old man with frequent attacks of ventricular tachycardia (VT) due to arrhythmogenic right ventricular dysplasia (ARVD) developed severe right heart failure following cryoablation of the multiple VT focuses. Inotropic support and intraaortic balloon pumping failed to maintain the systemic circulation, so that we performed the right heart bypass (RHB) using a heparin-coated tube and roller pump. With the use of RHB, systemic circulation improved. We attempted to wean the patient off after 14 days RHB support. However this was unsuccessful because of poor RV function, and RHB was recommenced. The patient finally died of multiple organ failure on the 21st postoperative day, but the major organ function was well maintained for at least two weeks. The heparin-coated tube and roller pump system is easy to handle, and is suitable as a short term lifesaving adjunct for severe right ventricular failure.

Five patients with isolated stenosis of the left main coronary artery or stenotic ostial lesions underwent direct coronary artery surgery. These surgical approaches included vein patch angioplasty in 2 cases, punch out endarterectomy in 1 case, and resection of the thickened aortic wall and transaortic endarterectomy in 2 cases. Early results were satisfactory, except for one case who died due to severe LOS and MOF. In the late postoperative period, one case of vein patch angioplasty died due to cerebral bleeding, and in the other case, stenosis existed in position of distal patch anastomosis. Since direct coronary artery surgery was successful in both early and late postoperative fidings, it is believed to be useful and safe technique if the candidates are selected properly.

Ascending aorta-infrarenal abdominal aorta bypass was performed in 8 patients: 4 patients with dissecting aortic aneurysm, 3 patients with thoracic aneurysm and 1 patient with stenosis of the thoracic aorta after grafting for congenital thoracic aneurysm. Four patients who had aortic dissection underwent the thromboexclusion method, but thromboexclusion of the thoracic aorta occured in only one patient after additional clamp to the distal thoracic aorta. He is the only long-term survival in this series. The thromboexclusion method was also performed in two patients with infectious thoracic aortic aneurysm, but they died of aneurysmal rupture within 13 months after operation. One patient who undewent resection of a thoracic aneurysm with extra-anatomic bypass, developed respiratory insufficiency and paraplegia, and died of pneumonia. The patient with thoracic aortic stenosis is alive and well 11 years after operation. The indications of the thromboexclusion method for thoracic aneurysm should be limited only to very poor-risk patients who seem to be inaccessible to a direct approach. Ascending aorta-abdominal aorta bypass is recommended in cases of thoracic aortic stenosis.

Thirty-four patients with congenital cardiac disease were studied to evaluated the role of ultrafiltration after cardiopulmonary bypass without homologous blood transfusion. We used either polypropylene microporous hollow fiber hemoconcentrator (HC-30M or 100M) or polyacrylonitrile microporous hollow fiber hemoconcentrator (PHC-500). Ultrafiltration was useful in the reduction of fluid overloading after cardiopulmonary bypass with extreme hemodilution. Thirty-two patients tolerated the procedure uneventfully without donor blood transfusion and were discharged from the hospital. The values of hematocrit, serum protein and free hemoglobin increased significantly after ultrafiltration with either type of hemoconcentrator. However the degree of concentration of blood components was significantly higher with polyacrylonitrile hemoconcentrator than those with polypropylene hemoconcentrator. These results indicated that ultrafiltration was useful for maintaining water balance after cardiopulmonary bypass without homologous blood transfusion in pediatric cardiac surgery and that polyacrylonitrile microporous hollow fiber hemoconcentrator should be employed in patients with shorter bypass time and less hemolysis.

To estimate the blood compatibility during extracorporeal circulation, we designed mock circulation system consisted of a membrane oxygenator and vinyl circuit with roller pump. Primed with 200ml Ringer's acetate and 200ml of fresh whole human blood, mock circulation was worked at flow rate 0.5l/min for 6hr. Heparin was not primed, oxygenator did not fill any gases and circulation was keeping at 37°C. The thrombin-antthrombin complex and fibrinopeptide-A showed progressive increase and fibrinogen correspondingly decrease. Nevertheless, the plasmin α2 plasmin inhibitor complex and D-dimer showed minimal changes within normal range in spite of increasing fibrinopeptide B β 15-42. We can not find any signs of secondary fibrinolytic activity. On the other hand, the platelet was persistently activated as shown statistically significant increase in β-thrombogloblin and platelet factor IV. Significant elevations of complement 3a and 4a were seen with increase of complement 5a and activated oxygen productivity by neutrophilic leucocytes. In conclusion, moderate and limited blood alterations occurred in mock cardiopulmonary bypass circuit.

Transcatheter embolization of 25 aortopulmonary collateral arteries (7 bronchial arteries and 18 intercostal arteries) was attempted prior to intracardiac repair in 7 patients. The underlying disease was tetralogy of Fallot in 3 patients, pulmonary atresia with ventricular septal defect in 2, double-outlet right ventricle with ventricular septal defect and pulmonary stenosis in 1 and tricuspid stenosis with pulmonary atresia in 1. The intervals between embolization and intracardiac repair ranged from 0 to 17 days (mean 4.5 days). Embolization resulted in total occlusion in 7 bronchial arteries and 17 intercostal arteries, with an overall success rate of 96%. Complications included a coil dislodgement from a collateral artery into the aorta in one patient, necessitating surgical removal of the dislodged coil from the femoral artery, an exacerbation of cyanosis and dyspnea on exercise in 5, and slight fever in 2. In one patient with tetralogy of Fallot, who had 5 collateral vessels, transcatheter embolization caused hypoxemia, bradycardia and hypotension and therefore intracardiac repair was performed immediately after embolization. Aortopulmonary collateral arteries in patients with congenital heart disease can be effectively treated by transcatheter embolization. Embolization should be performed just before intracardiac repair because an excessive decrease in arterial oxygen saturation after embolization may require an emergency operation.