Beating heart aortic valve replacement after previous coronary artery bypass surgery with a patent internal mammary artery graft

Re-sternotomy for aortic valve replacement (AVR) in patients with a patent internal mammary artery (IMA) graft may present a challenging surgical problem. Thus, strategies to prevent IMA graft injury include avoiding its dissection and leaving the graft open. However, when aortic cross clamping and cardioplegia are required, this approach may be associated with cardioplegia washout, suboptimal myocardial protection, and anterior myocardial wall injury. We herein describe an alternative technique for AVR on the beating heart in 4 patients with patent IMA grafts. The IMA was left unclamped and continuous retrograde coronary sinus perfusion (RCSP) was administered. Additional simultaneous antegrade venous bypass graft perfusion was established according to the extent of native coronary artery disease as well as patency and level of aortic proximal anastomoses. Using additional coronary ostia backflow control, the aortic valve was successfully replaced on the beating heart in all four cases without perivalvular leak. Postoperatively, low creatine kinase-MB fraction levels and preserved or improved ventricular function suggested very good myocardial protection. No myocardial infarction occurred in any patient. In our experience, aortic valve replacement on the beating heart using simultaneous antegrade-retrograde blood perfusion is a safe and effective method in this challenging subset of patients to prevent myocardial injury and to minimize the risk of patent IMA injury.