P6576Use of atrioventricular nodal ablation after atrial fibrillation ablation failure: a nationwide cohort study

Atrial fibrillation (AF) catheter ablation is a validated therapy for patients with symptomatic AF after failure or intolerance to antiarrhythmic drug therapy. Despite improvements in ablation technique, 30 to 50% of the patients may have AF recurrences. The APAF-CRT trial recently demonstrated that atrio-ventricular node ablation (AVNA) and cardiac resynchronization pacing was superior to pharmacological therapy in reducing HF and hospitalization in patients with permanent AF. The purpose of the study was to quantify the use of AVNA after AF catheter ablation and to find independent predictors factors associated with AVNA in this setting. Methods This French longitudinal cohort study was based on the national hospitalization database covering hospital care from the entire population. The data for all patients admitted in France from January 2010 to December 2015 were collected from the national administrative database, the PMSI (Programme de Médicalisation des Systèmes d'Information). We included all patients, over 18 years old, with AF and at least one AF catheter ablation. Routinely collected medical information includes the principal or secondary diagnoses and procedures performed. Items from the baselines characteristics were pooled into a multivariate Cox model to identify predictors of AV node ablation. Results Of 1,663,284 patients identified with AF, 28,018 patients were treated with AF ablation (28% female, mean age 60±10 yo, 22,837 with 1 procedure, 4,576 with 2 procedures and 605 with 3 procedures). Of those 28,018 patients, there were only 369 patients (1.3%) treated with AVNA after a mean follow-up of 374±488 days (median 210, interquartile 15–798). AVNA was less commonly performed than redo AF ablation with 3 procedures, and among these latter patients, only 3.8% were treated with AVNA during follow-up. Most powerful independent predictors of AV node ablation (HR >1.7) were age≥75 yo, heart failure at baseline, abnormal renal function and valve disease. Other independent predictors for AV node ablation (HR 1.2–1.7) were age 65–74 yo, female gender, obesity, coronary artery disease, thyroid disorders, lung disease and hypertension. Conclusion Our findings indicate that AVNA is rarely used after AF ablation failure and is probably an underrated strategy in these patients for now. Considering evidence from the APAF-CRT trial indicating a beneficial effect on mortality of this treatment in symptomatic AF patients, a wider use of AVNA should be more widely proposed in these patients. Its optimal timing during rate and rhythm control management still remains to be established.