Department of Medicine, UMass Memorial Medical Center, Worcester, Massachusetts.
Division of Hematology/Oncology, Department of Medicine, UMass Memorial Medical Center, Worcester, Massachusetts.
Pharmacotherapy. 2020 Feb;40(2):174-177. doi: 10.1002/phar.2361. Epub 2020 Jan 16.
Thromboembolism related to a mechanical heart valve (MHV) is a major complication after surgical valve replacement. Warfarin remains as guideline-endorsed thromboprophylaxis in patients with MHVs. Alternative anticoagulation therapy for patients who do not tolerate or who fail warfarin is not adequately covered in the current guidelines. We report a case of successful long-term anticoagulation with enoxaparin in a patient with a mechanical aortic valve who had a contraindication to warfarin. The patient developed a left thigh hematoma requiring surgical evacuation 1 month after initiation of weight-based dosing of enoxaparin. His dose was then titrated based on peak anti-factor Xa levels (goal 0.6-1.0 IU/ml). He remained free of signs and symptoms of thromboembolic events, valve dysfunction, bleeding complications, or major adverse effects from long-term enoxaparin use for the next 13 years. Our case provides promising evidence of the potential role of enoxaparin in patients with MHVs in whom warfarin thromboprophylaxis is not possible. Meticulous monitoring of anti-factor Xa levels and dosage adjustments are crucial to treatment success.
与机械心脏瓣膜(MHV)相关的血栓栓塞是心脏瓣膜置换术后的主要并发症。华法林仍然是指南推荐的 MHV 患者的血栓预防治疗方法。对于不能耐受或对华法林治疗无效的患者,替代抗凝治疗在当前指南中没有得到充分涵盖。我们报告了 1 例机械主动脉瓣患者成功使用依诺肝素进行长期抗凝的病例,该患者对华法林有禁忌症。依诺肝素开始基于体重剂量给药 1 个月后,患者出现左大腿血肿,需要手术清除。然后根据抗因子 Xa 水平峰值(目标 0.6-1.0 IU/ml)调整剂量。在接下来的 13 年中,他没有出现血栓栓塞事件、瓣膜功能障碍、出血并发症或长期使用依诺肝素的主要不良反应的迹象和症状。我们的病例为依诺肝素在华法林血栓预防治疗不可行的 MHV 患者中的潜在作用提供了有希望的证据。仔细监测抗因子 Xa 水平和剂量调整对于治疗成功至关重要。