Dabigatran anticoagulation and Stanford type A aortic dissection: not a lethal coincidence

Abstract

Sir,We have read an interesting case report by Stein et al. 1 on aortic dissection in a patient on dabigatran. We have had a similar case of a female, 83 years old, under dabigatran therapy for permanent atrial fibrillation, admitted to the emergency room with a type A aortic dissection.Six hours earlier she had taken a 110 mg dose of dabigatran.The patient underwent a session of dialysis to reduce the plasma concentration of dabigatran but after an initial reduction it started to rise again 2 h after the end of the session. Admission laboratory tests showed a prothrombin time 190 s (normal 10.5-13.5 s), activated partial thromboplastin time 55 s (normal 25-37 s) and thrombin time > 150 s (normal 14-20 s). Dabigatran level was 240 ng/ml as measured by Hemoclot assay within the assay working range of 50-400 ng/ml. Renal function was impaired with estimated glomerular filtration rate 48 ml/ min.The post-dialysis concentration of dabigatran was 140 ng/ml and reached 100 ng/ml before surgery so factor VIII inhibitor (FEIBA) 20 U/kg was necessary to counter the anticoagulant activity with almost complete normalization of coagulation.The ascending aortic replacement was successfully performed.Other authors report the increase in dabigatran concentration and clotting times after dialysis probably due to the redistribution of dabigatran bound to plasma proteins and the shift out of the extravascular compartment. Chang and colleagues suggest to make several short dialytic cycles or a prolonged session in order to limit the rebound. 2 At the time we treated this case the antidote, idarucizumab, was not available in the facility where the patient was admitted. This monoclonal antibody, however, is indicated in similar scenarios for the emergency reversal of anticoagulation. 3 Haemodialysis is beneficial in mitigating bleeding risk and can be safely performed prior to emergency surgery but a rebound increase in dabigatran levels may be expected in the first hours after dialysis and FEIBA administration is a viable approach for the prevention of perioperative control of bleeding. References 1. Stein P, Bosshart M, Brand B, Schliker A, Spahn DR, Bettex D. Dabigatran anticoagulation and Stanford type A aortic dissection: lethal coincidence.

International consensus statement on the peri‐operative management of direct oral anticoagulants in cardiac surgery

“…Ciraparantag, which reduces the anticoagulant effect of FXa inhibitors, may also potentially be used for dabigatran, but clinical studies are pending . Haemodialysis has been reported to reduce plasma levels by 50% during a 4‐h treatment session and is effective in reducing dabigatran plasma levels in the pre‐ and postbypass period , but may not be applicable in the haemodynamically unstable, bleeding patient.…”

Delayed surgery in patients with acute type A aortic dissection who are receiving novel oral anticoagulants

“…1 Another 4 reports describe the patient surviving at the price Acquired: Aorta: Case Reports ACQ of significant transfusions, whereas 4 others describe the patient dying from intractable coagulopathy despite receiving massive amounts of blood products, coagulation factors, and, in 1 case, idarucizumab. [2][3][4][5][6][7][8][9] There is no consensus regarding the optimal management of these patients. The persistent risk of rupture must be weighed against the risk of intractable bleeding and multiple transfusions.…”

Answer to: Dabigatran anticoagulation and Stanford Type A aortic dissection: not a lethal coincidence

“…Dear Sir, We appreciate the opportunity to comment on the Letter to the Editor concerning "Dabigatran and Stanford type A dissection: not a lethal coincidence" by Marchetti et al 1 They refer to a female patient with a Stanford type A dissection and therapeutic dabigatran anticoagulation. In our original case report, 2 the patient died due to uncontrolled bleeding in the context of therapeutic plasma levels of dabigatran even after multiple exchange transfusions and more than 24 h after the last oral dabigatran intake.…”