Chapter 4: Evidence for the Early Use of Ablation and AADs Post-Ablation

Both catheter ablation and antiarrhythmic drugs (AADs) are effective treatments for atrial fibrillation (AF) and can be used individually or as complementary treatments. This chapter discusses the use of ablation for early rhythm control in AF, and the use of AADs post-ablation. Decisions on which therapeutic approach to pursue should be based on shared decision-making with the patient. The chapter reviews data from the CABANA trial, in which the intent-to-treat (ITT) analysis failed to show superiority for ablation versus AADs. Statistical significance was achieved, however, when using the pre-specified per-protocol and pre-treatment analyses. The discussion addresses the fact that data analysis was complicated by several factors: (1) not all members of the group assigned to ablation actually received ablation; (2) the AAD arm included rate control treatment without the use of AADs; (3) there were a large number of crossovers from the AAD arm to the ablation arm; and (4) many ablation-treated participants also used AADs. Results from the CABANA trial showed that ablation was better at preventing AF recurrence than AADs alone. Data from the STOP AF and EARLY AF trials that support the observation of ablation being superior to AADs alone for the reduction of recurrent AF are also reviewed. Many patients who undergo catheter ablation for AF either continue to use or need to restart AADs following ablation. This combination therapy is used by up to 40-50% of people at 1-year post ablation, as is clearly demonstrated by the results from the trials discussed above, in addition to those from the 5A trial, the POWDER AF trial, the AMIO-CAT trial, and a substantial meta-analysis. All these trials are reviewed in this chapter, noting that a variety of differences exist between the randomized clinical trials, including in ablation procedures, follow-up periods, physician experience, and AADs. Chapter 4 is summarized as follows.