9．下肢虚血を合併した急性大動脈解離：虚血の重症度評価と適切な手術手技

Acute Aortic Dissection Complicated by Lower Limb Ischemia：Evaluation of Ischemic Severity and Appropriate Surgical Technique

急性大動脈解離（AAD）に伴う臓器灌流障害の発症頻度は10～30％で，うち下肢虚血は約7～15％に発症すると報告されている1～3）．最近のInternational Registry of Aortic Dissection（IRAD）データベースからの報告では，Stanford A型急性大動脈解離（TAAD）に伴う臓器灌流障害の発症頻度は41％で，そのうち下肢虚血は17％に発症したと報告している4）．

The International Registry of Aortic Dissection （IRAD） reported that the incidence of limb ischemia in Stanford type A aortic dissection （TAAD） was 17％. The incidence of lower limb ischemia in Stanford type B aortic dissection （TBAD） ranged from 5.7％ to 30.0％, and in-hospital mortality was high in patients with lower limb ischemia complications. The reasons for this are：ischemia of other organs, especially intestinal ischemia, often coexists in patients with lower limb ischemia, resulting in a high incidence of myonephropathic metabolic syndrome （MNMS）；thoracic aortic open surgery is often prioritized under the concept of central repair, and prolonged lower limb ischemia time results in compartmentalization due to ischemia-reperfusion injury. The prolonged ischemic time in the lower extremity results in a high rate of compartment syndrome, MNMS, due to ischemia-reperfusion injury. Therefore, appropriate management of these two major complications is an important factor in saving the lives of patients with acute aortic dissection complicated by lower extremity ischemia.

Because the possibility of saving a patient’s life is improved by prompt diagnosis and treatment, a team approach is required to save lives and save limbs in close collaboration not only with surgeons but also with other departments and multiple professions.