The development of AF over time in patients with permanent pacemakers: objective assessment with pacemaker diagnostics demonstrates distinct patterns of AF

To describe the long-term patterns of atrial fibrillation (AF) in patients with permanent pacemakers. A total of 2092 pacemaker Holter downloads were analysed in 323 patients with dual chamber permanent pacemakers, describing a cumulative 1031 patient-years of beat-to-beat monitoring. Four subtypes of AF were applied: (i) non-progressive low-burden PAF (NPLB-PAF, n = 120): such patients never have >1% AF burden throughout follow-up; (ii) chronic progressive PAF (CP-PAF, n = 55): AF burden increases but is never 100%; (iii) relapsing-remitting PAF (RR-PAF, n = 78): AF burden has reduced at least once by more than 2% and is never 100%; (iv) persistent AF (PersAF, n = 70): 100% AF burden for at least 28 days. Overall, mean AF burden rose 0.34% per year (P < 0.0001). After accounting for age, heart failure (HF) had a significant interaction with AF burden (P = 0.0022), but HATCH score and CVA/TIA did not. There were no differences in the frequency or duration of monitoring between the four AF subtypes. Atrial fibrillation episode frequency discriminated between subtypes (P = 0.0004). Eighteen of 70 (26%) patients with PersAF had pacemaker documented episodes of sinus rhythm (i.e. reversion to 'paroxysmal AF') after the onset of PersAF. In this cohort, the development of AF over time appears more complex than current definitions suggest. Atrial fibrillation can remain low burden without progression, remit-relapse, or progress as is described in currently accepted definitions. More frequent episodes of AF indicated a favourable subtype. Persistent AF is not inevitable, and can revert to paroxysmal AF. NCT02016950, http://clinicaltrials.gov/show/NCT02016950.