Shaggy aortaを伴う弓部大動脈瘤に対するbrain isolation法を用いた全弓部大動脈置換術

Total Arch Replacement with Brain Isolation Technique for Arch Aneurysm with Shaggy Aorta

大動脈内に高度の浮遊粥状硬化病変を有するshaggy aortaを伴う弓部大動脈手術では，粥腫塞栓による脳合併症対策が重要である．特に体外循環の体循環および弓部分枝への順行性選択的脳灌流（SCP）の送血カニューレ挿入時，大動脈遮断操作時には，体外循環血流によるsandblasting effectに注意が必要である．粥腫塞栓による脳合併症を回避するため，体循環開始に先行し，SCPを体循環から分離して確立するbrain isolation法（BIT）が報告1）され，その後さまざまな手術の工夫と応用の報告2，3）がある．当院ではshaggy aortaを伴った弓部大動脈瘤に対して，脳合併症を回避すべくBITを用いた全弓部大動脈置換術（TAR）行っている．本稿では，当科で行っている手術手技の工夫および手術成績に関して報告する．

A shaggy aorta with a mobile atheromatous plaque in a thoracic lesion is considered a risk factor for cerebral infarction during aortic arch surgery. The brain isolation technique was introduced to prevent embolic stroke either by manipulating the severely atheromatous aorta, or by producing a sandblasting effect using the arterial jet in cardiopulmonary bypass. We performed total arch replacement with the aid of a brain isolation technique in four patients with aortic arch aneurysm complicated with a shaggy aorta between 2016 and 2020. Antegrade selective cerebral perfusion was established prior to systemic perfusion of the cardiopulmonary bypass. Total arch replacement using the frozen elephant technique was performed in all patients. There was no operative mortality, and all patients were discharged without major neurological complications. Therefore, the brain isolation technique could be a useful adjunctive method to prevent embolic stroke in patients who undergo total arch replacement for aortic arch aneurysm with a shaggy aorta.