P2845Recurrent atrial flutter and incidence of atrial fibrillation ablation after first-time ablation for typical atrial flutter: a nation-wide Danish cohort study

Abstract

Abstract Introduction Cavo tricuspid isthmus ablation (CTIA) is an effective first-line treatment for typical atrial flutter (AFL). However, many patients develop atrial fibrillation (AF) after successful CTIA. Knowledge about recurrent arrhythmia after CTIA mainly comes from small cohort studies with limited follow-up. Purpose To describe incidences of AFL re-ablation and AF-ablation after first-time CTIA in a nation-wide cohort. Method In the Danish National Ablation Registry we identified patients undergoing first-time CTIA during 2010–2016. Subsequent CTIA and AF-ablation procedures were identified until March 1st, 2018. We gathered information on patient comorbidities in the Danish National Patient Registry. Results We identified 2409 patients undergoing first-time CTIA. Median age was 66 (IQR 58–72) years, and 1952 (81%) were men. 78 (3%) had a history of AF. Acute procedural succes was achieved in 2288 (95%) patients. During mean follow-up of 4±1.7 years, 242 (10%) patients underwent CTI re-ablation and 326 (13.5%) ablation for AF. Baseline characteristics associated with CTI re-ablation included prolonged procedural time, unsuccessful first CTIA, age<75 years and CHA2DS2-VASc score<2. Hypertension, history of AF, age<65 years and CHA2DS2-VASc score<2 were associated with later AF-ablation (Table). Predictive characteristics Characteristics associated with CTI re-ablation HR 95% CI p-value Procedural time 1.003 (1.001–1.006) 0.01 Unsuccesful first CTIA procedure 3.42 (2.10–5.55) <0.0001 Age <75 years 1.52 (1.03–2.26) 0.04 CHA2DS-VAS2c score <2 1.45 (1.11–1.90) 0.01 Characteristics associated with later AF-ablation Hypertension 1.31 (1.02–1.69) 0.04 History of AF 1.70 (1.07–2.71) 0.03 Age <65 years 2.38 (1.89–3.01) <0.0001 CHA2DS-VAS2c score <2 1.77 (1.40–2.45) <0.0001 AF: Atrial fibrillation; HR: Hazard ratio. All HR's are adjusted for age, gender, hypertension, diabetes, heart failure, iscemic heart disease, valvular heart disease, chronic obstructive lung disease, chronic kidney disease and history of AF using Cox regression analysis. Conclusion In a nation-wide cohort undergoing CTIA for AFL, 10% of patients underwent CTI re-ablation and 13.5% were ablated for AF during mean follow-up of 4±1.7 years. Probability of undergoing a second ablation procedure was higher in younger patients with less comorbidity.