Narita Koichi, Amiya Eisuke, Komuro Issei
Department of Cardiovascular Medicine, The University of Tokyo, Tokyo, JPN.
Department of Therapeutic Strategy for Heart Failure, The University of Tokyo, Tokyo, JPN.
Cureus. 2020 Aug 30;12(8):e10143. doi: 10.7759/cureus.10143.
A 75-year-old man with a history of atrial fibrillation (AF) and anticoagulant therapy presented with a headache. Cerebral amyloid angiopathy (CAA) was diagnosed after MRI of the brain revealed cortical superficial siderosis, lobar intracerebral hemorrhage, and lobar microbleeds. Anticoagulant therapy was carefully discontinued. Several years later, he was admitted with sudden onset left upper-extremity weakness. In addition to CAA bleeding lesions, a diffusion-weighted brain MRI showed multiple infarct lesions of high signal intensity. The administration of edoxaban 7.5 mg/day (later increased up to 30 mg/day) prevented ischemic stroke recurrence without exacerbation of cerebral bleeding. This could indicate that CAA patients with AF who had previous adverse effects from warfarin can safely use newer direct oral anticoagulants, such as edoxaban, to prevent ischemic stroke without danger of cerebral hemorrhage. The superiority of edoxaban as compared with warfarin might be due to its antioxidant effect because vascular oxidative stress plays a causal role in CAA-induced cerebrovascular dysfunction, CAA-induced cerebral hemorrhage, and CAA formation itself. We explained the beneficial effect of edoxaban for CAA by the mechanism of oxidative stress in the paper.
一名有房颤病史且接受抗凝治疗的75岁男性出现头痛症状。脑部MRI显示皮质浅表性铁沉积、脑叶脑出血和脑叶微出血后，诊断为脑淀粉样血管病（CAA）。抗凝治疗被谨慎停用。几年后，他因突发左上肢无力入院。除了CAA出血性病变外，脑部弥散加权MRI显示多个高信号强度的梗死灶。每日服用7.5毫克（后增至每日30毫克）的依度沙班可预防缺血性卒中复发，且不会加重脑出血。这可能表明，曾因华法林出现不良反应的CAA合并房颤患者可安全使用新型直接口服抗凝药，如依度沙班，以预防缺血性卒中且无脑出血风险。依度沙班相较于华法林的优势可能归因于其抗氧化作用，因为血管氧化应激在CAA所致脑血管功能障碍、CAA所致脑出血以及CAA形成本身中起因果作用。我们在本文中通过氧化应激机制解释了依度沙班对CAA的有益作用。
