Faucher Loïc, Marchandot Benjamin, Carmona Adrien, Ohana Mickael, Trimaille Antonin, Morel Olivier
Hôpital Civil, Strasbourg, France.
Front Cardiovasc Med. 2023 Aug 8;10:1164432. doi: 10.3389/fcvm.2023.1164432. eCollection 2023.
Bioprosthetic valve thrombosis is a complication of transcatheter aortic valve replacement (TAVR). It is believed to be platelet independent, mainly driven by contact phase activation, and more likely to be targeted by oral anticoagulant (OAC).
We report case of an 86-year-old man with history of TAVR, who presented an early TAVR aortic valve thrombosis occurring in the context of heparin-induced thrombocytopenia (HIT) and pulmonary embolism. The patient rapidly recovered and was discharged 17 days after readmission. OAC by Coumadin was administered for 3 months. Chest tomography after 3 months showed the disappearance of the hypoattenuated leaflet thickening.
Although HIT has been fully described and is known for being a prothrombotic disorder, this is the first case report of aortic valve thrombosis after TAVR due to HIT. HIT is rare but possibly lethal. Diagnosis is based on pre-test probability evaluation with the 4T clinical score and confirmation with laboratory evidence of anti-PF4/heparin complexes and positivity of a functional test. Management of HIT is based on heparin discontinuation, and treatment of thrombotic complication with direct anti-IIa inhibitor or anti-Xa inhibitor. According to our knowledge, this case represents the first report of bioprosthetic valve thrombosis after TAVR due to HIT.
生物瓣血栓形成是经导管主动脉瓣置换术（TAVR）的一种并发症。人们认为它与血小板无关，主要由接触相激活驱动，更可能成为口服抗凝剂（OAC）的治疗靶点。
我们报告了一例86岁有TAVR病史的男性患者，该患者在肝素诱导的血小板减少症（HIT）和肺栓塞背景下发生了早期TAVR主动脉瓣血栓形成。患者迅速康复，再次入院17天后出院。使用香豆素进行OAC治疗3个月。3个月后的胸部断层扫描显示叶瓣增厚低密度影消失。
尽管HIT已被充分描述且以血栓前状态疾病而闻名，但这是首例因HIT导致TAVR术后主动脉瓣血栓形成的病例报告。HIT罕见但可能致命。诊断基于使用4T临床评分进行的预测试概率评估，并通过抗PF4/肝素复合物的实验室证据和功能测试阳性进行确认。HIT的管理基于停用肝素，并使用直接抗IIa抑制剂或抗Xa抑制剂治疗血栓并发症。据我们所知，本病例是首例因HIT导致TAVR术后生物瓣血栓形成的报告。
