Atrial fibrillation in transfemoral transcatheter aortic valve implantation

Background Atrial fibrillation (AF) is a frequent comorbidity in patients who undergo transcatheter aortic valve implantation (TAVI). In addition, new-onset AF can occur as a complication of TAVI. However, how AF affects clinical outcomes remains conflicting. Purpose Evaluate the impact of pre-existing and new-onset AF on outcomes after TAVI. Methods CENTER2 is an international patient-level pooled cohort that includes patients who underwent TAVI between 2007 and 2022. Clinical outcomes were compared in patients with and without pre-existing AF. Rates of new-onset atrial fibrillation at 30 days were evaluated in patients without pre-existing AF that survived the index hospitalisation, since new-onset AF shares a competing risk with death. Results A total of 23,320 patients (56.1% female; mean age 81.5±6.7 years) underwent transfemoral TAVI of whom 6579 (28.2%) had pre-existing atrial fibrillation. 1-year mortality was higher patients with AF than without (19.0% vs 14.2%, adjusted HR 1.39, 95%CI 1.26-1.53, p<0.001). Stroke rates were comparable at 30-day (2.4% vs 2.2%, p=0.47) and 1-year (7.2% vs 6.9%, p=0.57) follow-up. Only 76.8% (n=3140) of patients with AF were discharged on oral anticoagulation. Stroke rates in these patients did not differ significantly from those with AF and anticoagulation at discharge: at 30-day (2.5% vs 2.0%, p=0.33) and 1-year follow-up (6.5% vs 6.4%, p=0.98). Use of vitamin K antagonists was associated with higher bleeding rates compared to patients on direct oral anticoagulants (8.2% vs 4.6%, OR 1.83, 95%CI 1.35-2.49, p<0.001). There was no difference in 30-day stroke rates by anticoagulant type (1.7% vs 1.4%, p=0.54). However, 1-year stroke rates were lower in patients treated with vitamin K antagonists (5.5% vs 9.9%, OR 0.53, 95%CI 0.28-1.00, p=0.05). In patients without pre-existing AF who survived the index hospitalization, 681 (6.2%) had new-onset AF after TAVI. There were no differences in 1-year mortality (11.1% vs 8.6%, p=0.09) in patients with and without new-onset AF. Similarly, stroke incidence was comparable at 30 days (2.2% vs 2.1%, p=0.92) and 1-year (8.1% vs. 6.0%, p=0.16). Only 48.1% of patients with new-onset AF were discharged on anticoagulation, but there were no significant differences in rates of stroke compared with patients with new-onset AF and anticoagulation (1.8% vs 2.7%, p=0.50). However, new-onset AF was associated with higher rates of 30-day major bleeding (12.0% vs 6.7%, OR 1.90, 95%CI 1.49-2.43, p<0.001). Conclusions Pre-existing and new-onset AF in patients that undergo TAVI are not associated with higher risk for stroke.