Methods:
Clinical outcomes were evaluated in 222 patients undergoing first-time catheter ablation of NPAF with a CFS RFA catheter (SmartTouch, Biosense Webster) at New York University (NYU) Langone Health. Group 1 included 111 patients that underwent PVAI followed by stepwise linear ablation between July 2014 and September 2015, while Group 2 included 111 patients that underwent PVAI followed by LA PWI between October 2015 and August 2016. Our group changed ablation strategies from a linear stepwise approach to LA PWI and this research evaluates the effectiveness of this change. Index and repeat ablations were performed by the same five high-volume (>150 AF ablations per year) operators in each cohort. NPAF was defined as AF lasting more than seven days or a duration of greater than 48 hours requiring cardioversion.9 The incidence of atrial arrhythmia recurrence of >30 seconds in duration was evaluated in each cohort and stratified by AF or atrial tachycardia (AT) as well as by persistence of the arrhythmia. Amiodarone was discontinued at least one month prior to ablation and any antiarrhythmics started after the ablation were discontinued within 4 to 8 weeks after the procedure. After the index ablation, patients were scheduled for follow up in-office visits at 3, 6, 9, and 12 months, and every 6 months thereafter. At each visit, study assessments included a detailed medical history, physical exam, and 12-lead ECG. A 2-week mobile cardiac outpatient telemetry (MCOT) monitor was performed prior to each scheduled in-office visit in patients without implanted arrhythmia monitoring. Arrhythmia recurrence was defined as either (1) a sustained atrial arrhythmia within the 90-day blanking period that required a repeat ablation or (2) an atrial arrhythmia that occurred after the 90-day blanking period and was captured on a resting 12-lead ECG or lasted longer than 30 seconds on an ambulatory monitor. Persistence of AF or AT after index ablation was defined by the need for direct current cardioversion after the blanking period or sustained AF or AT at the time of repeat ablation. Patient follow-up was censored for the purposes of survival analyses at time of last follow up if less than 3 years after their first procedure, but did not have a second ablation.