Cerebral blood flow after hybrid distal hemiarch repair

Aortic arch disease can be treated with hybrid repair (extra-anatomic bypass plus placement of aortic endoprostheses), but there is controversy about whether a bypass from one relatively small vessel will provide adequate blood flow to the entire brachiocephalic system. We, therefore, compared flow volumes before and after hybrid repair.

We reviewed the records of 16 patients who underwent a hybrid distal hemiarch repair between October 2010 and May 2012. The procedure consisted of debranching of the left subclavian and left common carotid arteries, creation of a bypass to these vessels from the right subclavian artery by using a T-shaped synthetic graft, and placement of a stent graft. Preoperative and postoperative measurements of blood flow volume in the carotid and vertebral arteries and of regional cerebral blood flow were performed in ~70% of the patients.

Perioperative complications were one new-onset, fatal acute aortic dissection and two minor strokes. No major endoleaks occurred. Postoperatively, mean flow volumes in the right and left common carotid arteries, right and left internal carotid arteries, and right and left vertebral arteries were 423 and 393, 271 and 189, and 87 and 80 ml/min, respectively. Regional cerebral blood flow in the territories of the anterior, middle and posterior cerebral arteries was not significantly different from preoperative levels, as assessed both with and without administration of acetazolamide.

Hybrid distal hemiarch repair preserved regional cerebral blood flow and vasoreactivity, although flow in the common and internal carotid arteries was right-side dominant postoperatively.