How are arteries in the aortic arch repaired?

Frequently, we have an emergency where we have to cover one of the branch vessels, aortic arch vessels. Most of the time, the artery goes to the left arm, which is the left subclavian artery. Sometimes we cover it and do not do a bypass to maintain or regain blood flow to it. And more and more, we are doing a bypass to the carotid subclavian bypass to keep flow to the left arm in the left side of the brain and then put a stengraft. So the stengraft will cover the left subclavian artery after we put a carotid subclavian bypass. This also could be done in a more elective fashion if we want to plan a thoracic endovascular repair, or T-Var, and do a bypass to create what we call a landing zone for the endograft, which means you have enough of healthy aorta to attach our top portion of the endograft to the walls of the aorta before any of the blood flow to the arch vessel starts. And that is also a hybrid repair that we use in patients that cannot have a full open repair or cannot wait to have a custom-made device done for those patients.