Coronavirus-2019 (COVID-19) predisposes patients to arterial and venous thrombosis commonly complicating the clinical course of hospitalized patients and attributed to the inflammatory state, endothelial dysfunction, platelet activation and blood stasis. This viral coagulopathy may occur despite thromboprophylaxis and raises mortality; the risk appears highest among critically ill inpatients monitored in the intensive care unit. The prevalence of venous thromboembolism in COVID-19 patients has been reported to reach ∼10-35%, while autopsies raise it to nearly 60%. The most common thrombotic complication is pulmonary embolism, which though may occur in the absence of a recognizable deep venous thrombosis and may be due to pulmonary arterial thrombosis rather than embolism, resulting in thrombotic occlusion of small- to mid-sized pulmonary arteries and subsequent infarction of lung parenchyma. This micro-thrombotic pattern seems more specific for COVID-19 and is associated with an intense immuno-inflammatory reaction that results in diffuse occlusive thrombotic micro-angiopathy with alveolar damage and vascular angiogenesis. Furthermore, thrombosis has also been observed in various arterial sites, including coronary, cerebral and peripheral arteries. Biomarkers related to coagulation, platelet activation and inflammation have been suggested as useful diagnostic and prognostic tools for COVID-19-associated coagulopathy; among them, D-dimer remains a key biomarker employed in clinical practice. Various medical societies have issued guidelines or consensus statements regarding thromboprophylaxis and treatment of these thrombotic complications specifically adapted to COVID-19 patients. All these issues are detailed in this review, data from meta-analyses and current guidelines are tabulated, while the relevant mechanisms of this virus-associated coagulopathy are pictorially illustrated.

2019 冠状病毒 (COVID-19) 使患者容易出现动脉和静脉血栓，这通常会使住院患者的临床病程复杂化，原因是炎症状态、内皮功能障碍、血小板活化和血瘀。尽管进行了血栓预防，但这种病毒性凝血病仍可能发生并增加死亡率；在重症监护病房接受监测的危重住院患者中，这种风险似乎最高。据报道，COVID-19 患者静脉血栓栓塞的患病率达到约 10-35%，而尸检将其提高到近 60%。最常见的血栓并发症是肺栓塞，虽然肺栓塞可能在没有可识别的深静脉血栓形成的情况下发生，但可能是由于肺动脉血栓形成而不是栓塞造成的，导致中小型肺动脉血栓闭塞并随后发生梗塞肺实质。这种微血栓模式似乎对 COVID-19 更具特异性，并与强烈的免疫炎症反应相关，导致弥漫性闭塞性血栓性微血管病，伴有肺泡损伤和血管新生。此外，在不同的动脉部位也观察到血栓形成，包括冠状动脉、脑动脉和外周动脉。与凝血、血小板活化和炎症相关的生物标志物已被建议作为 COVID-19 相关凝血病的有用诊断和预后工具；其中，D-二聚体仍然是临床实践中使用的关键生物标志物。各个医学会已经发布了专门针对 COVID-19 患者的血栓预防和治疗这些血栓并发症的指南或共识声明。本综述详细介绍了所有这些问题，汇总了荟萃分析数据和当前指南，并以图解说明了这种病毒相关凝血病的相关机制。