Acute pulmonary embolism (APE) is a serious cardiovascular disease. In recent years, there has been an increasing detection rate of patients with APE accompanied by thrombocytopenia, presenting a dual challenge of thrombosis and bleeding. Current research is mainly based on successful case reports, with a certain research gap in clinical evaluation and treatment options.

To explore the clinical characteristics and prognosis of APE patients complicated with thrombocytopenia, so as to provide a basis for clinical diagnosis and treatment.

A total of 21 patients with APE accompanied by thrombocytopenia who were admitted to the Emergency Department, Peking University People's Hospital from January 2015 to January 2020 were included as the study subjects and categorized into the severe bleeding group (n=7) and mild/no bleeding group (n=14) based on their bleeding conditions; as well as the multiple-site thrombosis group (n=7) and pulmonary artery thrombosis groups (n=14) based on the presence of thrombosis at sites other than the pulmonary artery; and into the death group (n=5) and survived group (n=16) based on their survival status. Clinical data were collected and compared between groups.

A total of 21 APE patients with thrombocytopenia were included in this study, involving 7 males and 14 females, with an average age of (63.2±18.9) years. The etiologies included immune thrombocytopenic purpura (5 cases), antiphospholipid syndrome (4 cases), eosinophilia (3 cases), drug-related thrombocytopenia (2 cases), systemic lupus erythematosus (2 cases), cancer-associated thrombocytopenia (2 cases), and 3 cases of unknown etiology. Nineteen patients received anticoagulant therapy. Fibrinogen and fibrinogen/albumin ratios were higher in the pulmonary artery thrombosis group than in the multi-site thrombosis group (P<0.05). The proportion of males and mean platelet volume were lower in the severe bleeding group than in the mild/no bleeding group, and the proportion of multi-site thrombus and centrocyte/lymphocyte ratio were higher than the mild/no bleeding group (P<0.05). The proportion of anticoagulation therapy and platelet count in the death group were lower than those in the survival group, and the proportion of heart rate, mean platelet volume/platelet ratio, and cancer-associated thrombocytopenia were higher than those in the survival group (P<0.05) .

APE patients with thrombocytopenia are at risk for multiple thrombotic events. Anticoagulant therapy contributes to improved clinical prognosis. Anticoagulation therapy based on platelet count is not significantly associated with serious bleeding events. Platelet count, platelet-related parameters, and other coagulation-related parameters contribute to the interpretation of thrombotic burden, bleeding risk, and clinical prognosis.

急性肺栓塞（APE）是严重的心血管疾病，近年APE合并血小板减少患者的检出率不断增加，存在血栓和出血的双重问题，目前研究主要以成功的病例报道为主，存在一定的临床评估和治疗方案的研究缺口。

探讨APE合并血小板减少患者的临床特征和临床预后，为临床提供诊疗依据。

回顾性纳入2015年1月—2020年1月北京大学人民医院急诊科就诊的APE合并血小板减少患者21例为研究对象。将患者按照出血情况分为严重出血组（7例）和轻微/无出血组（14例）；依据患者是否合并除肺动脉以外其他部位血栓将患者分为多部位血栓组（7例）和肺动脉血栓组（14例）；依据患者死亡情况将患者分为死亡组（5例）和存活组（16例）。收集患者临床资料并进行组间比较。

本研究共纳入APE合并血小板减少患者21例，其中男7例，女14例，平均年龄（63.2±18.9）岁。分析病因，免疫性血小板减少性紫癜5例，抗磷脂抗体综合征4例，嗜酸性粒细胞增多症3例，药物相关血小板减少2例，系统性红斑狼疮2例，肿瘤相关性血小板减少2例，病因不明3例。19例患者进行抗凝治疗。肺动脉血栓组纤维蛋白原、纤维蛋白原/白蛋白比值高于多部位血栓组（P<0.05）。严重出血组男性比例、平均血小板体积低于轻微/无出血组，多部位血栓比例、中心粒细胞/淋巴细胞比值高于轻微/无出血组（P<0.05）。死亡组抗凝治疗比例、血小板计数低于生存组，心率、平均血小板体积/血小板比值、肿瘤相关血小板减少比例高于生存组（P<0.05）。

APE合并血小板减少患者存在多血栓事件风险，抗凝治疗有助于改善临床预后，依据血小板计数开展抗凝治疗与严重出血事件无相关性，血小板计数、血小板相关参数及其他凝血相关参数有助于血栓负荷、出血风险及临床预后的评估。