TAVR and atrial fibrillation
How to manage?
Elderly patients who develop aortic stenosis can be treated with TAVR. Dual antiplatelet therapy with ASA and clopidogrel is the treatment of choice to prevent thrombotic phenomena in the deployed prosthesis. However, these elderly people, in general, are rich in comorbidities and the balance between bleeding and thrombosis is always very delicate.
With the development of atrial fibrillation, the individual starts to have an indication for oral anticoagulation and both the vitamin k antagonist and direct anticoagulants (DOACs) are alternatives for chronic use, but add risks of severe bleeding, mainly combined with other medications that predispose this situation.
An interesting trial was recently published in the prestigious New England Journal of Medicine comparing patients who had an indication for the use of DOACs due to the presence of atrial fibrillation separated into 2 groups: those who were taking clopidogrel in combination after TAVR and those who were taking DOAC only.
It was seen that patients who used DOAC combined with clopidogrel had higher bleeding rates over 1 year. Bleeding from a puncture accident during the procedure was excluded from the analysis, but the difference found was mainly caused by minor bleeding.
The risk of bleeding was greater in the first month, a period of concomitant use of medications, since clopidogrel was discontinued after the third month.
For patients using vitamin K antagonists, the result had already been published in other studies and was very similar to this finding with the use of DOACs. The association with antiplatelet increased the incidence of bleeding and, in the case of warfarin, there was no increase in thrombotic phenomena.
Here we must remember another recent publication on the use of anticoagulants after TAVR (click here). In patients with no precise indication for the use of medication, such as in the presence of AF, rivaroxaban increased the incidence of bleeding, and was therefore not indicated as a protective therapy after implantation of TAVR.
Much of the justification for this work was based on the treatment of coronary syndromes in individuals who used oral anticoagulants. In this group of patients, it is known that the use of triple therapy with ASA, clopidogrel and anticoagulant increases the risk of bleeding and does not reduce the risk of thrombosis when only clopidogrel is used as an antiaggregant. In TAVR, as there is a need to use the antiplatelet agent for at least 3 months until the prosthesis is epithelized, understanding if only the oral anticoagulant would be enough could reduce the risk of bleeding in a high-risk population.
So far, this is what we have:
- Combination therapy brings more risks of bleeding than just the use of anticoagulant in a patient with a formal indication as atrial fibrillation.
- Patients with no indication for use should not use oral anticoagulants as prophylaxis for prosthetic thrombotic events.
- For patients with AF, the analysis of outcomes such as mortality and stroke was not adequate and no inference can be made so far.
1 – Feit F. How Un-POPular Is Bleeding in Patients with TAVI ?. N Engl J Med. 2020; 382 (18): 1761-1763.
2 – Nijenhuis VJ, Brouwer J, Delewi R, et al. Anticoagulation with or without Clopidogrel after Transcatheter Aortic-Valve Implantation. N Engl J Med. 2020; 382 (18): 1696‐1707.