Sinus rhythm duration after direct current cardioversion for persistent atrial fibrillation and long-term outcomes after subsequent catheter ablation.
Tang P-T., Almorad A., Vetta G., Chan JH., Hampshire J., Eastwick-Jones K., Eaton H., Robertson CA., Griffiths RLM., Hurst A., Leo M., Kirubakaran S., Arockiam S., Aldred M., Mercer B., Ahluwalia N., Assadi R., Hunter RJ., Valli H., Ali K., Haldar S., Betts TR., Pedersen M., Rajappan K., Bashir Y., Wijesurendra RS., Ginks MR.
BACKGROUND: Patients undergoing catheter ablation (CA) for persistent atrial fibrillation (PsAF) experience high rates of AF recurrence. Direct current cardioversion (DCCV) is often performed prior to CA, with variable post-DCCV duration of sinus rhythm (SR). OBJECTIVE: We aimed to determine whether shorter SR duration after DCCV is associated with AF recurrence after subsequent CA. METHODS: We performed an international multicentre retrospective study of patients undergoing first-time CA for PsAF between 2015 and 2024 with a prior DCCV. SR duration after the last DCCV preceding CA was recorded. The primary outcome was freedom from atrial arrhythmia after CA (after a 56-day postablation blanking period). RESULTS: 938 patients undergoing first-time CA for PsAF were identified from six centres and categorised by post-DCCV SR duration: <7 days (group 1, n=212); 7-31 days (group 2, n=236); and >31 days (group 3, n=490). Over median post-CA follow-up of 511 days, 512 patients (55%) experienced atrial arrhythmia recurrence. There was no significant between-group difference in freedom from atrial arrhythmia (log-rank p=0.10). When analysed as a continuous variable in a Cox regression model, there was no association between post-DCCV SR duration and time to first recurrence of atrial arrhythmia (HR per 10-day increment 1.00, 95% CI 1.00 to 1.01, p=0.07). In secondary analyses, there were significantly more blanking period arrhythmias in groups 1 and 2 compared with group 3 (both pairwise p<0.001), and presentation for CA in persistent atrial arrhythmia was associated with a time-dependent increased risk of atrial arrhythmia recurrence compared with presentation in SR. CONCLUSION: In this large multicentre cohort, shorter duration of SR after DCCV was associated with blanking period arrhythmia after subsequent CA, but we did not find evidence of an association with long-term AF recurrence. Clinicians should consider these findings when making decisions regarding suitability for CA or predicting long-term CA success.