Abstract 640: Clinical studies in New Onset versus Established Persistent Atrial Fibrillation: Insights from Device Based Monitoring of Total Atrial Fibrillation Burden
BACKGROUND: Device based monitoring of total atrial fibrillation (AF) burden in paroxysmal AF has suggested significant discordance in detection of recurrent AF when compared with intermittent monitoring.
OBJECTIVES: To examine behaviour of recurrent AF after the initial development of persistent AF to optimize methods for AF detection in clinical practice or trials.
METHODS: 330 pts with history of paroxysmal AF & bradycardia (mean age 70 ± 10 yrs; 61% male) were implanted with a pacemaker that automatically recorded the cumulative daily AT/AF burden during a followup period of 401 ± 123 days. Persistent AT/AF was defined as 7 consecutive days with ≥ 23 hours of AT/AF on the device data logs. Antiarrhythmic drug therapy must be stable for at least 7 months.
RESULTS: 78 pts (24%) progressed to persistent AT/AF at a mean interval of 147 ± 149 days. Follow up after initial detection of persistent AF ranged from 14 to 499 days. In 54 pts with 180 days or more follow-up after initial detection of persistent AF, 4 pts (8%) never returned to sinus rhythm (SR). After 90 days, 32 of 51 pts (63%) either remained in or returned to persistent AF & 30 of 45 pts (67%) did so at 6 mos. AF recurrence in the subgroup of patients with SR restoration is shown in figure⇓.
A single persistent AF event predicts a high likelihood of failure to maintain SR within 90 days.
Event rates of recurrent persistent AF can be high even in new onset persistent AF populations within six months.
Intermittent AF monitoring techniques could be increasingly accurate and/or even adequate in persistent AF populations with a minimum follow up of six months since the onset of the first episode of persistent AF.