RESUMO
AIMS: Recent studies have tested different atrial pacing rates, modes, and sites for preventing atrial fibrillation (AF) recurrence. Present generation pacemakers offer reliable electrograms (EGMs) storage for optimizing the arrhythmia diagnosis. Based on these EGMs, the study objective was to assess the rate of AF recurrence at two different pacing rates. METHODS: Thirty patients suffering exclusively from symptomatic brady-tachy syndrome (BTS) resistant to > or =2 drugs, were implanted with a DDDR pacemaker. After a 5-days observation period, the DDD pacing rate was randomly programmed at 60 bpm (-15 bpm hysteresis) or at 80 bpm for 12 weeks. The two sequences were crossed over at the end of this fixed period or when earlier symptomatic AF recurred. Antiarrhythmics were maintained. Stored EGMs of > or =4 s duration identified all AF recurrence. RESULTS: Thirty patients (17 males, 77.2 +/- 8.1 years old) were included. One patient withdrew prematurely for severe heart failure associated with AF recurrence and rapid ventricular response. For the remainder of the 29 patients, fast atrial pacing neither provoked symptoms nor haemodynamic change. AF recurred in 16 patients paced at 60 (-15) bpm (mean time: 29 days; range 1-61) and in 9 patients paced at 80 bpm (mean time: 55 days; range 5-83) (P < 0.05). AF recurrence was asymptomatic in 50% of patients. CONCLUSIONS: These results confirm that rapid atrial pacing is 1) significantly effective for preventing AF recurrence in symptomatic BTS patients, and 2) haemodynamically well tolerated.
