Division of Hematology & Oncology, Oregon Health & Science University, Knight Cancer Institute, Portland, OR, USA.
Division of Hematology & Oncology, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, Portland, OR, 97239, USA.
J Thromb Thrombolysis. 2018 Apr;45(3):397-402. doi: 10.1007/s11239-018-1614-5.
Acute limb ischemia (ALI) is generally secondary to cardioembolism or progression of peripheral vascular disease, however, a discrete population of patients with ALI exists in which no precipitant is ever established. Unlike cryptogenic arterial occlusion in other arenas, such as cryptogenic stroke, cryptogenic acute limb ischemia (cALI) has not been well-described, and no routine management has been established. The aim of this study is to describe patients with cALI, and the risk of recurrence based on the treatment they received. We performed a retrospective cohort study of patients evaluated for ALI at a single academic center, excluding patients with known peripheral artery disease, polytrauma, critical illness, or a history of recent vascular access. Out of 608 individual patients analyzed, 37 were deemed to have cALI on their initial presentation. After extended follow up, 29 patients were eventually found to have a precipitating cause, with 8 patients remaining cryptogenic. On follow up, the overall rate of recurrent ALI was 13% in the group eventually found to have a precipitating cause, and 25% in the cALI group. The median time to recurrence was 16.5 months in the precipitated acute limb ischemia (pALI) group, and 23.3 months in the cALI group. Of pALI patients who recurred, 40% did so despite being therapeutic on anticoagulation. None of the recurring cALI patients were therapeutically anticoagulated. Based on our analysis, nearly 20% of patients presenting with ALI in the absence of known risk factors will remain cryptogenic. Rates of recurrent ALI in patients who present with cALI are significant, particularly in patients who are not maintained on anticoagulation. This suggests that the etiology of ALI in patients without peripheral vascular disease may not have a strong bearing on treatment decisions, and that indefinite anticoagulation may be warranted in patients with no obvious cause on presentation. Future studies are needed to better gauge the risk for bleeding complications and to provide a better understanding of the risks and benefits of recurrence and complications of anticoagulation over time.
急性肢体缺血（ALI）通常继发于心源性栓塞或外周血管疾病的进展，但有一部分 ALI 患者始终无法确定病因。与其他领域（如隐源性卒中）的隐源性动脉闭塞不同，隐源性急性肢体缺血（cALI）尚未得到很好的描述，也没有建立常规的治疗方法。本研究旨在描述患有 cALI 的患者，并根据他们接受的治疗方法来评估其复发风险。我们对单一学术中心评估的 ALI 患者进行了回顾性队列研究，排除了已知外周动脉疾病、多发创伤、重症疾病或近期血管通路史的患者。在分析的 608 名患者中，有 37 名患者在初次就诊时被认为患有 cALI。经过长期随访，最终发现 29 名患者有明确的病因，8 名患者仍为隐源性。在随访期间，最终确定有明确病因的患者中急性肢体缺血再发的总体发生率为 13%，cALI 组为 25%。在 pALI 组中，复发的中位时间为 16.5 个月，cALI 组为 23.3 个月。在复发的 pALI 患者中，40%尽管接受了抗凝治疗仍复发。无复发的 cALI 患者接受了抗凝治疗。根据我们的分析，近 20%的无已知危险因素的 ALI 患者将持续为隐源性。cALI 患者发生 ALI 再发的比例较高，尤其是未接受抗凝治疗的患者。这表明，无外周血管疾病的 ALI 患者的病因可能对治疗决策影响不大，对于无明显病因的患者，可能需要长期抗凝治疗。未来的研究需要更好地评估出血并发症的风险，并随着时间的推移更好地了解抗凝治疗的复发和并发症的风险和益处。
