Anticoagulatory treatment and clinical outcomes after transcatheter aortic valve implantation: results from 45,598 patients of the German Aortic Valve Registry (GARY)
Authors: Hohmann C , Pfister R , Frerker C , Beckmann A , Walther T , Bleiziffer S , Ensminger S , Bekeredjian R , Seiffert M , Sinning J M , Moellmann H , Beyersdorf F , Herrmann E , Balaban Ü , Kuhn E W 
Published: November 2023

Abstract

Background
Transcatheter aortic valve implantation (TAVI) has developed to the therapy of choice for patients with symptomatic severe aortic stenosis who are inoperable or at high or intermediate operative risk for surgical aortic valve replacement. However, the optimal anticoagulant therapy post-TAVI still remains a matter of debate and individual patient characteristics and comorbidities lead to the prescription of different regimens in clinical practice.

Purpose
This study investigates current anticoagulant treatment patterns and clinical outcomes in patients after TAVI in a real-world population.

Methods
The German Aortic Valve Registry (GARY) is a prospective, multicenter all-comers registry enrolling patients undergoing invasive treatment for aortic valve disease. From January 2011 to December 2019, 141,790 patients from 92 hospitals performing TAVI procedures in Germany were enrolled. Different anticoagulant treatment regimens were assessed at hospital discharge for patients after TAVI procedures. All-cause mortality and the combined endpoint "cardiac and cerebrovascular events" containing myocardial infarction (MI), stroke, transient ischaemic attack (TIA), aortic prosthesis re-intervention and all-cause mortality in the first year after TAVI were examined by treatment regimen.

Results
The study population comprised 45,598 patients with TAVI between 2011 and 2019: 46.5 % received dual antiplatelet therapy (DAPT), 25.7 % oral anticoagulation (OAC) plus antiplatelet therapy, 15.0 % single antiplatelet therapy (SAPT), 6.8 % OAC monotherapy, 4.7 % triple therapy and 1.3 % did not receive any anticoagulant medication. The majority of patients with oral anticoagulation were prescribed VKA (66.8 %) compared to DOAC (33.2 %). After adjustment for baseline confounders, cardiac and cerebrovascular event free survival did not differ significantly between patients with SAPT and DAPT (HR 0.94, 95% CI 0.89-1.00, p = 0.07), albeit the risk of all-cause mortality was slightly increased in SAPT (HR 1.24, 95% CI 1.12-1.37, p &lt;0.001) and all regimens containing oral anticoagulation (OAC mono: HR 1.24, 95% CI 1.08-1.42, p = 0.002, OAC duo: HR 1.23, 95% CI 1.13-1.35, p &lt; 0.001, OAC triple: HR 1.25, 95% CI 1.08-1.45, p = 0.003) compared to dual antiplatelet regime. In patients with OAC, the risk of all-cause mortality (HR 0.99, 95% CI 0.89-1.10, p = 0.81) and cardiac and cerebrovascular event free survival (HR 1.07, 95% CI 0.97-1.18, p = 0.17) was not significantly different in patients with DOAC-containing regimens when compared to VKA-containing regimens.

Conclusions
In an analysis from one of the world’s largest national registries of patients undergoing TAVI, we found comparative effectiveness of SAPT vs. DAPT and DOACs vs. VKA after TAVI with respect to cardiac and cerebrovascular events. The increased risk of all-cause mortality in patients with antiplatelet monotherapy might be confounded by unmeasured morbidity but requires further attention.Multivariate: Reference group DAPTMultivariate: Reference group VKA