Long-term outcomes following atrioventricular node ablation in a single centre - the importance of symptom resolution after pace and ablate strategy in AF

Abstract Atrial fibrillation (AF) is the commonest clinical arrhythmia worldwide with rising incidence, as are populations living with concomitant comorbidities such as heart failure. The so-called pace and ablate strategy is normally reserved for individuals with symptomatic atrial fibrillation whom have failed AF ablation or are at higher risks from atrial ablation due to comorbidities or have another pacing indication. Despite its use, patients may remain symptomatic after atrioventricular node (AVN) ablation and selection of patients for AV node ablation has been challenging due to the irreversible nature and risks of heart failure or pacemaker syndromes.(1) We describe a single centre long-term follow-up of patients undergoing AV node ablation after device implantation. Methods: From an electrophysiology (EP) registry of 1380 patients in a single centre in the UK over 2007-2025, 134 patients whom undergone AVN ablation after device implant for symptomatic AF were included in this study. Baseline characteristics on demographics, comorbidities, medication use, device type, imaging results (echo, ECG, Holter), EP parameters, and follow-up data on symptoms, heart failure admission, mortality, stroke, MI, Ejection fraction were collected. Ethical approval was obtained from the hospital ethics committee(Ref N5273). Results: Of 134 patients, the mean age was 73.7(10.3)years, 51.9% female, with a high proportion of heart failure 65(48.5%), mean EF% 44.41(16.0), LA size 44.9(17.34)ml/m2, with a mean follow-up of 6.38(3.6)years. 130 (97.0%) achieved successful AVN ablation and atrio-ventricular dysynchrony. Resolution of symptoms occurred in 64(47.8%) of individuals after AVN ablation, while symptoms remained present in 70(52.2%) of individuals. All-cause mortality occurred in 34 (25.4%) of individuals (Figure1). When compared to those with resolution of AF symptoms, residual symptoms was associated with a higher risk of heart failure admissions (p=0.019), and mortality (p=0.0013). Kaplan-Meier survival analysis illustrates a higher mortality risk with residual symptoms HR 2.71(1.33-5.50) (p=0.0059 via Log-rank test) (Figure2). Univariate regression analyses identified symptoms being inversely linked to Cardiac Resynchronisation Therapy(CRT) device use HR0.73(0.53-0.98)(p=0.041), and a trend of symptoms associated with ischaemic cardiomyopathy HR2.77 p=0.093, and heart failure admissions HR2.9 (p=0.060), these were maintained in a multivariate logistic regression including ischaemic cardiomyopathy HR6.5(p=0.042) and Device Type HR0.33 (p=0.043). Conclusions: Despite prior evidence suggesting improvement in symptoms after AVN ablation for AF, persistence of symptoms despite AVN ablation may highlight underlying risks of mortality or heart failure admissions, which suggest reports of symptoms after AVN ablation warrants further investigation and management. Careful selection of patient and device type prior to pace and ablate is recommended.Figure1.Study Population Figure2.KM Curve Symptoms Mortalityrisk