Paced P-wave duration as a significant predictor for atrial high-rate episodes in patients with cardiac implantable electronic devices

Abstract

Funding Acknowledgements Type of funding sources: None. Background Atrial pacing can unmask or aggravate a preexisting interatrial block (IAB). Purpose The purpose of our study was to determine whether atrial pacing is associated with the development of atrial high-rate episodes (AHRE) during follow-up. Methods Patients with cardiac implantable electronic devices (CIED), no previous documented atrial fibrillation, and with a 6-month minimum follow-up were included. Sinus and paced P-wave duration were 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. Results 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 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). In a multivariate analysis, a paced P-wave ≥160 ms (OR: 1.84; 95% CI [1.03–3.28]; p = 0.038), a CHA2DS2-VASc score ≥4 (OR: 2.01; 95% CI [1.13–3.55]; p = 0.016), and a LA SI dimension ≥ 55 mm (OR 2.69; 95% CI [1.48–4.90]; p = 0.001) were independent predictors augmenting AHRE. 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.