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Selectivity: Who really should be offered AF ablations?

Precisionmedical management specifically tailors care to each individual patient, and no arrhythmia demonstrates this statement better than atrial fibrillation (AF). Differences in patient symptomatology and comorbidities, together with advances inmedicine and invasive procedures, create many permutations of therapeutic options. Which strategy is best is a question that applies not only to the individual patient, but also to broad therapeutic and medical economic landscapes. With retrospective data reporting the total annual cost for treatment of nonvalvular AF to be as much as $26 billion in 2010,1 and the prevalence of AF estimated to be 12 million people by 2050 in the United States alone, the cost of treating AF will grow. Much of this cost is due to recurrent hospitalizations, emergency room (ER) visits, outpatient follow-ups, and repeat procedures such as cardioversions andechocardiograms. Contributing to the escalating cost of treatment for AF is the rise in the volume of catheter ablation for AF. What was initially a prolonged, exhausting procedure of hunting triggering atrial premature beats has now become, in the most basic sense, a substrate modification process. Innovations in mapping tools and energy sources, enhanced success rates, and decreased procedure times have resulted in over 75,000 catheter ablations forAFperformedduring 2009–2012 in the United States alone.2 But is it effective, in the societal sense? Does catheter ablation for AF slow or reverse the escalating cost of treating patients with AF, and reduce the cost of total health care? In this issue of Journal of Cardiovascular Electrophysiology, Samuel et al. report their findingsonhealthcare resourceutilization change in a cohort of patients before and after catheter ablation for AF.3 Between April 1, 2005 and March 31, 2011, 1,556 patients in Québec were identified as the study cohort. These patients underwent AF catheter ablation, with run in data collected 24 months before ablation and follow-up data for at least 24months after ablation. The authors found a progressive increase in healthcare utilization over the 24-month period leading up to the first ablation. Hospitalizations for AF and AF-related cardiovascular conditions were significantly reduced in the 12 months postablation compared with the 12 months preablation, as did ER and outpatient visits, cardioversions, and echocardiography. The decline in resource utilization extended to 24 months after index ablation. The study cohort had a mean age of 56.5 years, with relatively few comorbidities and a low mean CHA2DS2-VASc score of 1.2. Importantly, a separate analysis showed that an increase in healthcare utilization was seen in the 25% of patients who required repeat ablations. The most significant and sustained decline in healthcare utilization was seen in patients who required a single procedure within the first 2 years. The present study by Samuel et al.3 corroborates prior data that reduction in healthcare resource utilization post catheter ablation for AF is most evident in patients who have the highest chance of a successful first procedure. Repeat ablations are associated with higher total medical cost, over and above the cost of additional procedures.2 Indication for the procedure, definition of procedure success, patient characteristics, and procedural quality all play a role in the likelihood of repeat procedures. If the indication for ablation is the assumption that maintenance of sinus rhythm can reduce strokes and mortality, then the definition of success would be highly dependent on AF recurrence, and the threshold for repeat ablation would be low. Currently, however, there are no large randomized controlled studies demonstrating that maintenance of sinus rhythm by ablation procedures reduces strokes or mortality. Reduction in healthcare utilization would not be expected if ablations were performed for this indication. On the other hand, there is convincing evidence that AF ablation can provide symptomatic relief. Attempting to understand patients’ symptoms and correlating those symptoms to AF is a time consuming but crucial part of treating patients with AF. To be sure, there are patients with paroxysmal AF who always know when they are in AF and can describe debilitating symptoms that resolve immediately upon termination of AF. For the most part, however, patients’ symptoms are vague, and frequently occur in the setting of obesity, sedentary lifestyle, untreated sleep apnea, and ongoing tobacco use. Aggressive risk factor modification was shown in the ARREST-AF study to