A 79-year-old man was admitted for thoracoabdominal aortic aneurysm repair. He had already twice undergone coronary artery bypass grafting, 19 and 2 years previously. The value of the ejection fraction of the left ventricle was 36%, measured by ventriculography; and transthoracic echocardiography revealed moderate aortic valve regurgitation. In the presence of aortic valve regurgitation or coronary artery disease, myocardial perfusion under hypothermic fibrillatory arrest may be significantly impaired. Therefore, to maintain a beating heart we used separate perfusions of the upper and lower body that enabled individual temperature control of each organ. The femoral and axillary arteries were cannulated, and a long cannula was inserted into the right common femoral vein and positioned in the right atrium. Cardiopulmonary bypass was established, and the upper body was mildly cooled until the pharyngeal temperature was 33°C, while the lower body was cooled until the bladder temperature reached 20°C. Mild hypothermia of the upper body maintained the beating heart, and deep hypothermia in the lower body provided adequate protection to the spinal cord. Furthermore, in a case of aortic valve regurgitation and low left ventricular function, left ventricular venting is essential for the heart. However, it was difficult to insert the venting tube through the apex of the left ventricle or through the left inferior pulmonary vein; therefore, we selected the left main pulmonary artery for left ventricular venting, and maintained a non-working beating heart. After cardiopulmonary bypass was discontinued, cardiac function was good although a bleeding tendency became apparent. Postoperatively, the maximum dose of dopamine we needed was only 3γ. There were no remarkable complications and the patient was discharged on postoperative day 30. This experience suggests that pulmonary artery venting and separate perfusion of the upper and lower body to individually control organ temperatures is a useful procedure for thoracoabdominal aortic aneurysm repair in patients with low left ventricular function.

Since November 1999 we have attempted to use a right heart bypass (RHB) system for beating heart coronary artery bypass grafting (CABG), which system produce better exposure of lateral and posterior wall of the heart and so enable us to facilitate bypass grafting to these branches. We report on our initial clinical experience with this system and the purpose of this study is to evaluate the efficacy of this system. To clarify the efficacy of the RHB system, we compared the intraoperative and postoperative clinical course, as well as outcome, between patients who underwent beating heart CABG with RHB and patients without RHB. Seventy-seven patients underwent beating heart CABG with RHB (RHB group) between November 1999 and December 2001. In the same period, 88 patients underwent beating heart CABG without RHB. Of these latter, 30 patients needed displacement of the beating heart in order to expose target coronary arteries (OPCAB group). Perioperative clinical parameters were compared between the groups. Patients in the RHB group received more grafts (2.4±0.6) than patients in the OPCAB group (2.0±0.2, p=0.002). There were no hospital deaths in either group. While displacing the beating heart, SvO₂ decreased and pulmonary artery pressure increased in both groups. Nevertheless, the value of SvO₂ was significantly higher in RHB group while displacing to expose the circumflex region (p=0.048) and the distal right coronary artery region (p<0.01). The effect of elevation of pulmonary artery pressure in the RHB group was lower than that in the OPCAB group, but it was not statistically different. Water balance during operation was 2, 898±1, 019ml in the RHB group and the 2, 237±807ml in OPCAB group (p=0.002). Body temperature following operation was 36.0±0.8°C in the RHB group and 36.5±0.8°C in the OPCAB group (p<0.01). However, no differences were found in postoperative blood loss, required transfusion, duration of mechanical ventilation, ICU stay and hospital stay. No patient had postoperative complications related to the RHB system. The introduction of the RHB enabled bypass grafting to posterior wall vessels with better exposure and under greater hemodynamic stability. Therefore we think it a very effective support system which enable multiple coronary revascularization on beating heart CABG.

A 72-year-old woman had undergone resection and graft replacement of the proximal ascending aorta for a DeBakey type II aortic dissection. She presented again 7 years later with progressive dyspnea and a cough. Computed tomography confirmed an aortic arch aneurysm and Doppler echocardiography demonstrated aortopulmonary shunting. Cardiac catheterization revealed a fistula between the aorta and pulmonary artery with a 54.3% left-to-right shunt and a Qp/Qs of 2.19. Operative repair was performed under profound hypothermic circulatory arrest with selective cerebral perfusion. The aortopulmonary artery fistula was closed from within the aneurysm using an equine pericardial patch and the transverse aortic arch was resected and replaced with a graft. The patient recovered uneventfully and was discharged on postoperative day 43.