IntroductionDrivers are increasingly studied ablation targets for atrial fibrillation (AF). Focal and rotational activities (FAs/RAs) have been identified in various mapping methods and recent meta-analyses suggest that ablation at these sites has both short term and long term efficacy in treating AF. Most of these sites lay remote to the pulmonary veins, which may explain the limited success of pulmonary vein isolation (PVI) ablation alone.PurposeThe main objective was to compare the outcomes, extended to 30-months follow-up period, with regards to freedom from atrial arrythmia after PVI and FAs/RAs ablation vs. standard approach PVI with additional lines as per operator judgement. Secondly, to study the anatomical distribution of FAs/RAs and their frequency across the left atrium (LA) post PVI.MethodsWe conducted a single-centre retrospective observational study of 60 cases with persistent AF, having undergone de novo radiofrequency (RF) ablation by a single operator- 40 patients had standard PVI ablation and 20 had FAs/RAs mapped and subsequently ablated in addition to PVI. Sequential high-density mapping of LA in AF was performed post PVI using validated automated algorithm CARTOFINDER in CARTO 3 (multielectrode catheter applied for 30 seconds at each anatomical location) to detect FAs/RAs. Follow up information post index procedures were collected using electronic hospital records. The primary outcome was freedom from atrial arrythmia identified using Alive Cor remote monitoring, Holter and ECGs. All data were analysed using SPSS software program v.29 and XLSTAT.ResultsBaseline cohort demographics were comparable in both groups, importantly for age, gender and LA size (table 1). The Kaplan Meier survival analysis at the 30-months end-point (figure 1) suggests that trends in maintaining sinus rhythm was superior in those who had FAs/RAs ablated. The log-rank test confirmed that there was statistically significant difference in AF freedom between the two ablation strategies (p=0.035). There was no significant difference in the number of additional ablation lines created in both groups (p=0.54). A total of 279 areas of interest (AOIs) were mapped (average 13.95 applications per patient), with a total of 84 FAs and 3 RAs detected. The left atrial appendage (LAA) hosted the majority (n=35, 41.6%) of FAs/RAs among all 9 segments of LA -anterior (n=15), roof (n=13), floor (n=6), posterior, septal, lateral, RPVA and LPVA (figure 2).Abstract 12 Table 1Demographics of study and control groupsAbstract 12 Figure 1Kaplan Meier survival analysis showing AF freedom at end pointFigure omitted. See PDFAbstract 12 Figure 2Frequency of focal and rotational activities as per anatomical segments of left atriumFigure omitted. See PDFConclusionLong term follow up revealed the addition of FAs/RAs ablation with PVI in persistent AF resulted in significantly lower AF recurrence compared to PVI with additional lines only, both short and long term. Further studies with a larger cohort looking at this innovative technology with such improvement in AF burden is recommended.