Significance of fragmented QRS complexes for predicting new-onset atrial fibrillation after cavo-tricuspid isthmus dependent atrial flutter ablation

Abstract Background Atrial fibrillation (AF) and cavo-tricuspid isthmus (CTI) dependent atrial flutter (AFL) are two separate entities that coexist in a significant ratio of patients. In patients with CTI ablation of AFL, the decision to hold anticoagulation often becomes an issue. Objective This study aimed to describe the incidence of the development of AF after CTI ablation in patients without a history of AF and to identify the risk predictors for the occurrence of AF. Methods The present study included 120 consecutive patients (106 males, 68±12 years) who underwent radiofrequency catheter ablation (RFCA) of typical AFL since 2010. Patients with any history of AF prior to RFCA were excluded. The P wave and QRS morphology, characteristics, and duration were evaluated by 12-lead electrocardiography the day after the ablation. Results During 3.6±2.6 years of follow-up after the RFCA, 49 patients (41%) developed new-onset AF. A univariate analysis revealed that the presence of fragmented QRS complexes (fQRS) (Hazard ratio [HR], 4.63; 95%CI 2.31-9.29, P 120ms, and biphasic morphology in the inferior leads (HR, 4.44; 95%CI 2.45-8.01, P Conclusion The present study indicated that new-onset AF developed in a significant proportion of patients undergoing AFL ablation. The presence of fQRS complexes and advanced IAB were predictors of new-onset AF.