Richardson Aaron, Shah Stuart, Harris Ciel, McCulloch Garry, Antoun Patrick
Department of Medicine, University of Florida College of Medicine Jacksonville, Jacksonville, FL, USA.
Department of Cardiology, University of Florida College of Medicine Jacksonville, Jacksonville, FL, USA.
Case Rep Cardiol. 2017;2017:3090273. doi: 10.1155/2017/3090273. Epub 2017 Nov 22.
Heart valve replacement with a mechanical valve requires lifelong anticoagulation. Guidelines currently recommend using a vitamin K antagonist (VKA) such as warfarin. Given the teratogenic effects of VKAs, it is often favorable to switch to heparin-derived therapies in pregnant patients since they do not cross the placenta. However, these therapies are known to be less effective anticoagulants subjecting the pregnant patient to a higher chance of a thrombotic event. Guidelines currently recommend pregnant women requiring more than 5 mg a day of warfarin be switched to alternative therapy during the first trimester. This case report highlights a patient who was switched to alternative therapy during her first pregnancy and suffered a devastating cerebrovascular accident (CVA). Further complicating her situation was during a subsequent pregnancy; this patient continued warfarin use during the first trimester and experienced multiple transient ischemic attacks (TIAs). This case highlights the increased risk of thrombotic events in pregnant patients with mechanical valves. It also highlights the difficulty of providing appropriate anticoagulation for the pregnant patient who has experienced thrombotic events on multiple anticoagulants.
使用机械瓣膜进行心脏瓣膜置换需要终身抗凝。目前的指南推荐使用维生素K拮抗剂（VKA），如华法林。鉴于VKA的致畸作用，对于孕妇而言，通常转而采用肝素衍生疗法是有利的，因为这些疗法不会穿过胎盘。然而，已知这些疗法作为抗凝剂效果较差，会使孕妇发生血栓事件的几率更高。目前的指南建议，每天需要超过5毫克华法林的孕妇在孕早期应转而采用替代疗法。本病例报告重点介绍了一名患者，她在首次怀孕时转而采用替代疗法，并发生了毁灭性的脑血管意外（CVA）。使她的情况更加复杂的是，在随后的一次怀孕中，该患者在孕早期继续使用华法林，并经历了多次短暂性脑缺血发作（TIA）。本病例突出了机械瓣膜置换术后孕妇发生血栓事件的风险增加。它还突出了为在多种抗凝剂治疗下发生过血栓事件的孕妇提供适当抗凝治疗的困难。
