Disease progression after ablation for atrial flutter compared with atrial fibrillation: A nationwide cohort study

Aims: The aim of this study was to study the risk of death and development of arrhythmia and/or subsequently heart failure after an atrial flutter ablation procedure compared with an atrial fibrillation (AF) ablation procedure. Methods: This observational study is based on data from Danish nationwide health databases. Patients with a first-time ablation procedure for either atrial flutter or AF in the period 2000-2016 were included. Rates of renewed arrhythmia, heart failure or death were compared and reported as adjusted hazard ratios (HR). Results: The study population consisted of 2,004 and 3,803 patients with an incident atrial flutter or AF ablation procedure, respectively. All-cause mortality among atrial flutter patients was significantly higher compared with the AF group (HR 1.80, 95% confidence interval [CI] 1.39-2.35). The incidence of renewed arrhythmia without heart failure was lower in atrial flutter (HR 0.76, 95% CI 0.69-0.84). Renewed atrial flutter ablation and pacemaker implantations were significantly more frequent (HR 2.42, 95% CI 2.02-2.91 and HR 1.42, 95% CI 1.13-1.79, respectively) in atrial flutter compared with AF. The risk of heart failure was higher for atrial flutter, both after the initial ablation (HR 1.48, 95% CI 1.08-2.03), and after a further arrhythmia management event (HR 1.98, 95% CI 1.33-2.94). Conclusion: There was a higher mortality risk after atrial flutter ablation procedures compared with patients undergoing AF ablation. Rates of heart failure and further renewed (non-AF) arrhythmia management were higher in atrial flutter.