破裂性急性大動脈解離にステントグラフト内挿術施行後ヘパリン起因性血栓症を合併した1例

Endovascular Repair for Ruptured Acute Aortic Dissection Complicated by Heparin-induced Thrombosis

要旨　大動脈疾患に対するステントグラフト内挿術はその普及とともに侵襲がより少なくかつ効果は手術に匹敵する治療法としての地位を確実にしている．今回，Stanford B型大動脈解離破裂に対して緊急ステントグラフト内挿を行い救命した症例を経験したので報告する．術後急性腎不全を併発，血液浄化治療を要し一連の治療のなかでヘパリン起因性血栓症が判明した．発症時の血小板数が正常であったため判断に苦慮したが，早期にヘパリンを中止，アルガトロバンに変更し血栓症の拡大を来すことなく軽快した．一般的には血小板減少を伴うことが多いが，血小板数が正常のこともあり，ヘパリン起因性血栓症が疑われた時点での治療開始が重要と考えられた．

　Endovascular treatment for aortic disease has become popular, and is now confirmed as less invasive and equivalent to conventional surgery. We report a case of ruptured Stanford type B acute aortic dissection, which was successfully treated by endovascular aortic repair. Postoperative course was complicated by acute renal failure, requiring hemofiltration/hemodialysis, and the patient developed heparin-induced thrombosis. Platelet counts were normal at the onset of thrombosis, so it was quite difficult to obtain a definite diagnosis. Heparin was immediately discontinued, and replaced by argatroban, until the thrombosis settled down. In general this disease presents a low platelet count, but is normal in some cases, so it is essential to start treatment when heparin induced thrombosis is suspected.