With Great Power Comes Great Responsibility

A chieving reliable and reproducible lesion durability with radiofrequency ablation continues to vex cardiac electrophysiologists.Even pulmonary vein (PV) isolation-a theoretically simple and straightforward goal in the relatively thin-walled left atrium can be difficult to achieve durably, as chronic PV reconnections are often observed among patients with recurrent atrial fibrillation following prior PV isolation.1 The temptation is to consider ablating more-longer, with more power, or over larger area-at the index procedure, to potentially augment radiofrequency lesion durability in a single procedure, but these considerations are probably too simplistic, and are tempered by safety considerations.Collateral damage to noncardiac but adjacent tissues, most notoriously the esophagus, is a significant risk and a valid reason for limiting radiofrequency delivery on the posterior wall. 1 As we have begun to understand better the relative components of resistive and conductive heating on tissue injury, as well as differential effects in atrial versus ventricular tissue, some have proposed using high-power radiofrequency, which was previously restricted to ventricular ablation, for use in atrial ablations, but a very limited duration.Emerging evidence has shown that high-power, short-duration (HPSD) lesions may have great efficacy in achieving durable lesions without an increased risk for compromising safety.[2][3][4] Most notable is a recent multicenter, retrospective study by Winkle et al, 4 which included >10 000 patients undergoing nearly 14 000 ablations among several high-volume ablation centers using HPSD; this study demonstrated that the safety of such strategies seemed comparable to ablation performing using standard parameters.However, a logical concern for delivering high power to the thin posterior wall overlying the vulnerable esophagus is knowing when short duration of radiofrequency application is too long and when it is not enough.Although several animal and prior clinical studies have suggested the relative safety and improved efficacy of HPSD ablation, [2][3][4][5][6][7] there has remained a paucity of translational data utilizing preclinical findings to guide systematic and prospective clinical ablation, especially in comparing strategies of standard versus HPSD ablation.Additionally, among the clinical groups who have routinely adopted this practice, there are relatively wide ranges in powers (35-50 W) and durations (2-20 seconds depending on the power and site) used, as well as in technique (drag versus point-to-point).4 Along those lines, there remains some reticence in widespread adoption of the technique in the absence of data demonstrating the safety of such techniques, as well as a quantifiable, acute end point to guide when ablation at a given location is of sufficient duration to achieve durable efficacy but limited enough to prevent catastrophic collateral damage.When dealing with such thin tissue and such high powers, a prescriptive 2 to 10 seconds seems insufficient in ensuring that both of the latter EDITORIAL With Great Power Comes Great Responsibility Defining the Safety of High-Power Short-Duration Atrial Ablation