NEW YORK (Reuters Health) – Regardless of whether patients with atrial fibrillation are on warfarin or rivaroxaban (Xarelto), they have similar long-term survival and stroke rates after procedures to restore sinus rhythm, according to results from the ROCKET AF trial.
“The data are promising, but we are just beginning our journey in learning how to optimize the safe and effective use of these medications before, during, and after electrophysiologic procedures (such as ablation),” Dr. Jonathan P. Piccini from Duke University Medical Center, Durham, North Carolina told Reuters Health.
In the ROCKET AF trial, once-daily rivaroxaban was non-inferior to dose-adjusted warfarin for preventing stoke and CNS embolism in AF patients.
In this post hoc analysis, Dr. Piccini and colleagues investigated outcomes associated with cardioversion (either electrical or pharmaceutical) and catheter ablation in 321 patients in that trial.
The overall rate of cardioversion or catheter ablation was 1.44 per 100 patient-years in the warfarin arm and 1.46 per 100 patient-years in the rivaroxaban arm, according to the March 12th online report in the Journal of the American College of Cardiology.
On the day of cardioversion or ablation, 80% of patients were taking their assigned treatment, including 49% of patients undergoing ablation, 84% of those undergoing electrical cardioversion, and 91% of patients treated with rhythm-controlling drugs.
In the first 30 days after cardioversion or ablation, the overall rate of stroke or systemic emboli was 0.93%, and the mortality rate was 1.25%. During a median follow-up of 2.1 years, there was no difference in outcomes before and after cardioversion or ablation. There were no strokes while on treatment in the 79 patients who underwent AF ablation and only one stroke while off-treatment.
The rate of clinically relevant bleeding in the first 30 days after ablation or cardioversion was 2.18%, compared with 9.97% at baseline.
Hospitalization and clinically relevant bleeding were significantly more common after cardioversion or ablation than at baseline, the researchers note.
But stroke and survival rates after ablation or cardioversion did not differ significantly between patients randomized to warfarin and those in the rivaroxaban arm.
Several retrospective studies have suggested that long-term anticoagulation may not be necessary because of lower risks of stroke after catheter ablation than reported here, but these results suggest otherwise, the authors say.
“Treated patients receiving oral anticoagulation do not appear to be at excessive risk of stroke or systemic embolism in the long-term following cardioversion or AF ablation,” they conclude. “Therefore, clinicians should follow guideline recommendations and ensure adequate anticoagulation in moderate to high-risk patients.”
“In this limited cohort,” Dr. Piccini said, “the two drugs are associated with comparable safety and effectiveness following restoration of sinus rhythm with either cardioversion or catheter ablation. However, the use of novel oral anticoagulants following these procedures requires further study. The VENTURE AF study and the X-VeRT are two important clinical trials that will help physicians better understand how these drugs compare to one another in these settings.”
Dr. G. Y. H. Lip from the University of Birmingham Center for Cardiovascular Sciences in the UK told Reuters Health by email that while the new oral anticoagulants represent a major advance, “we need to see more data on some practical issues, for example, the safety during cardioversion, ablation, surgery, coronary interventions, etc.”
“The experience is small, but seems reassuring,” Dr. Lip said. “More data from further studies would be needed.”
In the meantime, Dr. Lip added, “For cardioversion, make sure patients are taking their drug prior to cardioversion.”
One of the 14 authors works for Johnson & Johnson Pharmaceutical Research & Development. Eleven of the other 13 authors report having received honoraria and/or research grants from Johnson & Johnson, which manufactures rivaroxaban.
J Am Coll Cardiol 2013.