(977) Post-Operative Use of Direct Oral Anticoagulants is Associated with Increased Risk of Recurrent Pulmonary Embolism Following Pulmonary Thromboendarterectomy

PurposeLife-long anticoagulation is required for patients following pulmonary thromboendarterectomy (PTE). Warfarin is the default anticoagulant; however, many patients request direct oral anticoagulants (DOACs) as they do not require monitoring or dietary changes. There is limited data on the safety and efficacy of DOACs following PTE, and the aim of this study is to better understand the bleeding and clotting risks in patients taking the two classes of medications after PTE in a non-trial setting.MethodsTo better understand real-world anticoagulation prescribing patterns and their potential implications following PTE, we retrospectively identified all patients who underwent PTE at our institution since July 2011 and determined their post-discharge anticoagulation regimen and the occurrence of complications using a standardized telephone questionnaire. Comparisons were made using Fisher's exact text.Results246 patients underwent a PTE at our institution after July 2011; our hospital electronic medical record indicated 33 (13%) died since their index operation. Of the 213 remaining, 72 (34%) patients were successfully contacted and 51 (23%) agreed to participate in the questionnaire for a response rate of 24%. The mean time from the index PTE for these 51 patients was 5.2 years +/- 3.2 years. Table 1 displays the results of the questionnaire. Nine patients (18%) who were discharged on warfarin switched to a DOAC. Notably, all 3 patients with a recurrent pulmonary embolism (PE) after PTE had been switched from warfarin to a DOAC prior to the PE (P = 0.04). Each required hospitalization (P = 0.04). There was no difference in bleeding complications between the groups.ConclusionPatients transitioned from warfarin to DOACs were more likely to experience recurrent PE and require in-hospital PE treatment. Larger studies assessing the use of DOACs in this population are needed to determine effectiveness and safety. Life-long anticoagulation is required for patients following pulmonary thromboendarterectomy (PTE). Warfarin is the default anticoagulant; however, many patients request direct oral anticoagulants (DOACs) as they do not require monitoring or dietary changes. There is limited data on the safety and efficacy of DOACs following PTE, and the aim of this study is to better understand the bleeding and clotting risks in patients taking the two classes of medications after PTE in a non-trial setting. To better understand real-world anticoagulation prescribing patterns and their potential implications following PTE, we retrospectively identified all patients who underwent PTE at our institution since July 2011 and determined their post-discharge anticoagulation regimen and the occurrence of complications using a standardized telephone questionnaire. Comparisons were made using Fisher's exact text. 246 patients underwent a PTE at our institution after July 2011; our hospital electronic medical record indicated 33 (13%) died since their index operation. Of the 213 remaining, 72 (34%) patients were successfully contacted and 51 (23%) agreed to participate in the questionnaire for a response rate of 24%. The mean time from the index PTE for these 51 patients was 5.2 years +/- 3.2 years. Table 1 displays the results of the questionnaire. Nine patients (18%) who were discharged on warfarin switched to a DOAC. Notably, all 3 patients with a recurrent pulmonary embolism (PE) after PTE had been switched from warfarin to a DOAC prior to the PE (P = 0.04). Each required hospitalization (P = 0.04). There was no difference in bleeding complications between the groups. Patients transitioned from warfarin to DOACs were more likely to experience recurrent PE and require in-hospital PE treatment. Larger studies assessing the use of DOACs in this population are needed to determine effectiveness and safety.