EDITORIAL COMMENTARY Quality of atrial fibrillation ablation: “Success is not final, failure is not fatal; is it the score that matters?” Sigfus Gizurarson, MD, PhD, Kumaraswamy Nanthakumar, MD From the Toronto General Hospital, University Health Network, Toronto, Ontario, Canada. In the current issue of HeartRhythm, Chinitz et al 1 present a novel scoring system (atrial fibrillation ablation [AFA] score) for evaluating the quality and success of catheter ablation for the treatment of paroxysmal atrial fibrillation (AF). We have paraphrased the words attributed to Sir Winston Churchill to give context to the transience of the wins and losses perceived in the greater battle against the formidable opponent of AF. We did this in order to shed light, and to pause and think of the direction AF ablation— the most prolific business in interventional electrophysiology —is taking. In their article, Chinitz et al underline the fact that a scoring system that incorporates quality and success has not been available for AF ablation and that the current use of AF recurrence as an outcome measure has limitations. The AFA score takes into account disparate factors such as lesion delivery, complications, and outcomes in order to evaluate the results and quality of AF ablation and allows for comparison of different techniques. This is achieved by incorporating 6 procedural features, half of which estimate efficacy and the other three reflect the relative acute safety of the procedure. A very strong emphasis is made on the total number of procedures performed, as seen in the relatively high score achieved by radiofrequency ablation in their article compared with emerging balloon techniques (cryo and laser), even though both redo and reconduction rates are quite similar among all methods, as seen in their Table 1. Although one would consider the novelty of this score may lie (if validated against meaningful outcomes) in its value in showing differences among manufacturers, operators, tech- niques, and institutions, the devil is always in the details. Like all creative concepts, this concept paper raises more questions than provides solutions to the problem at hand. What would this difference in score mean to the patient we hope to care for? The user of this score will not take into account the very premise for performing the procedure, that is, symptom relief. The score will only allow for comparison of nonpharmacologic treatment strategies that strictly target the pulmonary veins and does not permit comparison of AF ablation to drug treatment or emerging methods targeting areas outside the pulmonary vein antra, such as complex fractionated atrial electrograms, linear ablation, or rotor ablation. Finally, the formula for calculating the score may exaggerate small differences in treatment by multiplying factors such as reconduction ratio and rates of complications. More concerning would be the fact that a similar AFA score can be obtained with a method that has few complications but tends to have lower efficacy compared with a method that has severe complications but is very effective in terms of reducing AF burden and pulmonary vein reconduction. Leaving out the limitations of the score as a concept, it is important to step back and consider how it would help our patients. Consider the rationale and the state of outcome of catheter ablation of AF. Catheter ablation was launched as a treatment for paroxysmal AF in the late 90s by the pioneer- ing work of Haissaguerre et al 2 The rationale was that suppression of triggers could prevent episodes of paroxysmal AF, and patients suffering from this often bothersome arrhythmia potentially could be cured. Although with notable exceptions, most strategies used today target the area in the vicinity of the pulmonary veins, with the common endpoint of pulmonary vein isolation. Although initially believed to be higher, after long-term follow-up, the success rate with a single procedure usually is o50%, even in the most experienced hands, which is believed to be related to difficulties in achieving durable lesions. 3 Even with multiple procedures, ablation targets outside the pulmonary vein antra are often addressed. Even so, a considerable number of patients do not respond, and this figure is likely to increase further with even longer follow-up. We would have to consider the value of this score under this milieu of success and failure we face with catheter ablation of AF. The indication for ablation of paroxysmal AF is providing symptomatic relief of palpitations and accompanied symp- toms that usually are paralleled by a decrease in the arrhythmia burden. Treatments that may be effective, but carry unacceptable high risks, cannot be favored for the symptomatic treatment of an arrhythmia where several alternative treatments exist, including drug therapy. This is exemplified in the rise and fall of the high-intensity frequency ultrasound balloon, which demonstrated good clinical efficacy that unfortunately was offset by severe Address reprint requests and correspondence: Dr. Kumaraswamy Nanthakumar, Division of Cardiology, University Health Network, Toronto General Hospital, 150 Gerrard Street West, GW3-522, Toronto, Ontario, Canada, M5G 2C4. E-mail address: k.nanthakumar@uhn.on.ca. 1547-5271/$-see front matter B 2013 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.hrthm.2013.04.007