Industry-Sponsored Device Approval Studies
There have been a number of prospective randomized studies performed to evaluate the safety and efficacy of investigational devices used for AF ablation. These studies, such as THERMOCOOL IDE and STOP AF, have all provided important, high-quality data demonstrating the superiority of catheter ablation over drug therapy in drug refractory patients.462,684 Now that the utility of ablation over drug therapy in such patients has been accepted, many of the current studies are focused on comparing new technologies against approved devices in a noninferiority design. Although these studies are important from a safety and efficacy perspective and are often mandated by health approval bodies such as the FDA, the incremental yield in knowledge could be limited. Prespecified subgroup analyses, or the use of novel endpoints. could therefore be important to determine whether incremental value is added by the newer technology. TOCCASTAR, for example, demonstrated statistical noninferiority of CF-driven RF ablation to traditional RF. However, only in a post-hoc analysis did the trial show that optimal CF was associated with better outcomes, findings which should be viewed with caution due to the limitations of post hoc analyses. Testing of the durability of lesion sets such as PVI either after delayed waiting, drug (adenosine) challenge, or repeat electrophysiology study after 3 months might also help assess comparative efficacy more accurately. Industry must also look to see whether safety and efficacy parameters demonstrated in PAF also apply to nonparoxysmal populations. Several industry-sponsored studies are either being planned or are in progress to assess outcomes in this challenging population.