ABSTRACT
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, <i>p</i>=0.002). There were no hospital deaths in either group. While displacing the beating heart, SvO<sub>2</sub> decreased and pulmonary artery pressure increased in both groups. Nevertheless, the value of SvO<sub>2</sub> was significantly higher in RHB group while displacing to expose the circumflex region (<i>p</i>=0.048) and the distal right coronary artery region (<i>p</i><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 (<i>p</i>=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 (<i>p</i><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.
ABSTRACT
A 61-year-old woman had extracardiac unruptured aneurysms of the right and noncoronary sinuses of Valsalva, detected incidentally on electrocardiogram taken for a physical checkup. Two-dimensional echocardiography revealed that the sizes of the aneurysm of the right and noncoronary sinuses were 41×40 and 38×28mm respectively, but the shape of left coronary sinus was almost normal. The aortic valve leaflet was normal and the diameter of the aortic annulus and sinotubular junction was 23 and 27mm respectively. The Doppler color-flow echocardiogram showed moderate aortic regurgitation which resulted in prolapse of the right aortic cusp due to deformity of the annulus. We performed modified aortic root remodeling using a tailored Dacron graft to preserve the native aortic valve. Right and noncoronary sinuses of Valsalva were all excised with a small button of the aortic wall around the ostia of the right coronary artery. The left coronary sinus was left as it was. Then each commissure received sub-commissural annuloplasty and was pulled up. The defect of Valsalva was reconstructed with a 26mm Dacron tube graft, the proximal end of which was tailored to a scallop shape and that correspond to left coronary sinus was excised. The right coronary artery was reimplanted utilizing the Carrel patch method. Although we needed additional CABG to the right coronary artery and IABP support due to vasospasm of the right coronary artery, the postoperative course was uneventful. Echocardiography of the aortic valve before discharge showed a normal function without regurgitation.