Replacement aortic valve. This valve is being implanted by a surgeon to replace a patient's defective valve. The operation is treating a congenital defect of the bicupsid valve, and implanting an Epic Supra valve. The aortic valve lies between the heart's left ventricle (main pumping chamber) and the aorta, the body's largest artery, which distributes oxygenated blood from the heart to rest of the body.