Limitations
Several limitations should be acknowledged. This was an observational
and non-randomised study, however it is unlikely that a randomised trial
will ever be performed of NOAC versus VKA in HCM patients undergoing AF
ablation. Whilst our data are non-randomised it is hoped that they will
be a useful point of reference for others considering this approach.
Given the small sample size, this study was underpowered to demonstrate
non-inferiority of NOAC vs. VKA for most of the study comparisons (which
referred to events with a rate <10%). However, our
multicentre data constitute the largest cohort of HCM patients
undergoing AF ablation, and this is the first study to investigate the
use of NOAC in this setting. An interrupted oral anticoagulation
strategy with heparin bridging is no longer the standard of care and was
used in a few patients in this series. However, the observed numerical
differences were maintained even in sub-analyses excluding such
patients. We could not provide data on silent cerebral infarction, as
patients did not routinely undergo brain magnetic resonance imaging
post-ablation. Only a limited number of patients were on edoxaban or
dabigatran.