Study: VKAs Better Protect Aortic Valve Replacement Patients

June 14, 2019

Study finds higher Ischemic events and mortality in transcatheter valve replacement patients taking non-vitamin K antagonist oral anticoagulants versus vitamin K antagonists.

Ischemic events and mortality were higher in transcatheter aortic valve replacement (TAVR) patients taking non-VKA oral anticoagulants (NOACs) compared to those taking vitamin K antagonists (VKAs), a study says.

The study was published in the June 2019 JACC: Cardiovascular Interventions.

David Joccheim, MD, lead author, and his colleagues, set out to study NOACs versus VKAs because, while NOACs are superior to VKAs in nonvalvular atrial fibrillation (AF), their comparative performance among patients undergoing TAVR has been underinvestigated, he writes. Joccheim is professor at Ludwig-Maximilians University in Munich, Germany. The registry study enrolled 962 consecutive patients who underwent TAVR at four European centers and who were discharged on either NOACs or VKAs. A balloon-expandable valve was used in 62.7% of cases.

The combined incidence of all-cause mortality, myocardial infarction, and any cerebrovascular event measured at one year after TAVR was 21.2% with NOACs compared to 15% with VKAs.

However, the one-year incidence of any Bleeding Academic Research Consortium bleeds and all-cause mortality were comparable between the NOAC (33.9%) and VKA groups (34.1%).

Read More: Atrial Fibrillation Patients Often Overestimate Stroke and Bleeding Risks

“Chronic use of both NOACs and VKAs among patients in need of OAC after TAVR are comparable regarding one-year bleeding risk. The higher ischemic event rate observed with NOACs needs to be evaluated in large randomized trials,” Joccheim writes.

However, the authors of an editorial accompanying the study say the increased risk of ischemic events was of “borderline statistical significance.”

“While the authors attribute the increased risk of thrombotic complications with a NOAC to its lesser degree of anticoagulation effect compared with a VKA, this did not result in an increase in bleeding,” writes Dominick J. Angiolillo, MD, PhD, professor at the University of Florida College of Medicine-Jacksonville.

Still, the results of this study, along with another small study must be “seriously considered”, he adds.

“Despite the supportive data associated with the use of NOACs in patients with atrial fibrillation, including among those undergoing other interventional procedures such as coronary stenting, to date there is [a] lack of evidence that these should be preferred over a VKA after TAVR. Until then, NOACs should be used with caution and the choice of antithrombotic therapy should be individualized, taking into account patients’ bleeding and thrombotic risk profile,” Angiolillo writes.