Paced P-wave duration as a significant predictor for atrial high-rate
episodes in patients with cardiac implantable electronic devices
Abstract
Introduction: Atrial pacing can unmask or aggravate a
preexisting interatrial block (IAB). Our study aimed to determine
whether atrial pacing is associated with the development of atrial
high-rate episodes (AHRE) during follow-up. Methods and
Results: Patients with dual-chamber cardiac implantable electronic
devices (CIED), no previous documented atrial fibrillation, and with a
6-month minimum follow-up were included. In all patients, sinus and
paced P-wave duration was measured. AHRE was defined as an episode of
atrial rate ≥ 225 bpm with a minimum duration of 5 min, excluding those
documented during the first three months after implantation. Two hundred
twenty patients were included (75 ± 10 years, 61% male). After a mean
follow-up of 59±25 months, 46% of patients presented AHRE. Mean paced
P-wave duration was significantly longer than the sinus P-wave duration
(154±27 vs 115±18 ms; p < 0.001). Sinus and paced P-waves were
significantly longer in those who developed AHRE (sinus: 119±20 vs
112±16; p = 0.006; paced: 161±29 vs 148±23; p < 0.001). A
paced P-wave ≥160 ms was the best predictor of AHRE, especially those
lasting >24 h (OR 4.2 (95% CI) [1.6-11.4]; p = 0.004).
Conclusion: Atrial pacing significantly prolongs P-wave
duration and is associated with further development of AHRE. A paced
P-wave ≥160 ms is a strong predictor of AHRE and should be taken into
consideration as a new definition of IAB in the presence of atrial
pacing.