TAVI-related new onset AF increases stroke risk

New-onset atrial fibrillation (NOAF) following transcatheter aortic valve implantation (TAVI) is associated with higher rates of stroke, and can be independently predicted by larger atrial size and transapical approach, according to a study published recently in the Journal of the American College of Cardiology.¹

Researchers from the Quebec Heart & Lung Institute, Canada, examined prospectively collected data from a total of 138 consecutive patients with no prior history of atrial fibrillation (AF), who underwent TAVI with a balloon expandable valve. Patients were on continuous electrocardiogram (ECG) monitoring until hospital discharge, and NOAF was defined as any episode of AF lasting more than 30 seconds.

NOAF occurred in 44 patients at a median time of 48 hours following TAVI, and its incidence was increased in patients with larger left atrial size and those undergoing transapical TAVI. Up to 40% of the NOAF episodes occurred either during or within the 24 h following the procedure (figure 1). NOAF was associated with a higher rate of stroke/systemic embolism, but not a higher mortality, at 30 days and at 1-year follow-up.

Figure 1. Timing of first atrial fibrillation (AF) episodes following transcatheter aortic valve implantation in 44 patients with new-onset AF. Adapted from original

Figure 2. Duration of new-onset atrial fibrillation episodes following transcatheter aortic valve implantation. Adapted from original

The authors say the increase in cardioembolic events associated with NOAF offers an “important new insight into the mechanisms of cerebrovascular events following TAVI. Indeed, some…events seemed to be related to the no initiation of anticoagulant therapy upon documentation of the AF episode, which further emphasizes the clinical relevance of optimizing antithrombotic treatment in this high-risk subset of patients”.

They add that “future studies will have to determine the potential usefulness of implementing preventive strategies to reduce the occurrence of NOAF and its potentially devastating consequences in the setting of TAVI”.

References

1 Amat-Santos IJ, Rodés-Cabau J, Urena M, et al. Incidence, predictive factors, and prognostic value of new-onset atrial fibrillation following transcatheter aortic valve implantation. JACC 2012;59. doi:10.1016/j.jacc.2011.09.061.