Prolonged P-wave duration is associated with increased left atrial volume and delayed atrial conduction assessed by...

Atrial remodeling contributes to atrial fibrillation through structural and electrical alterations. Prolonged P-wave duration indicates conduction delay, while 3D mapping quantifies left atrial (LA) volume and conduction time.

This study enrolled 27 patients with atrial fibrillation (mean age 63 ± 10 years, 18 men) who underwent catheter ablation. Post-ablation 3D mapping was performed to assess atrial conduction time and LA volume. LA volume was also measured by transthoracic echocardiography. Electrocardiograms for analysis were obtained the following day while all patients were in sinus rhythm. Standard 12‑lead ECGs were recorded, and P-wave duration was digitally measured in each lead; the maximum value (Pmax) was used for analysis. Atrial conduction time and LA volume were compared between patients with Pmax ≥140 ms and those with Pmax <140 ms.

Pmax was significantly correlated with LA conduction time (R = 0.51, p = 0.016), total atrial conduction time (R = 0.62, p < 0.001), and the LA volume index (R = 0.48, p = 0.034). Patients with Pmax ≥140 ms showed delayed conduction and a larger LA volume index compared with those with Pmax <140 ms (LA conduction time 137.3 ± 41.0 vs. 104.5 ± 19.9, p = 0.010; total atrial conduction time 178.8 ± 40.0 vs. 140.8 ± 24.2, p = 0.007; LA volume index 73.7 ± 8.4 vs. 53.6 ± 16.0 mL/m², p = 0.014). Moreover, Pmax was significantly correlated with the LA volume index measured by echocardiography (R = 0.52, p = 0.013).

Prolongation of Pmax on electrocardiography was significantly associated with delayed atrial conduction and increased LA volume as measured by electro-anatomic mapping.