Delta wave notching time is associated with accessory pathway localization in patients with Wolff-Parkinson-White syndrome.

Purpose: Our aim was to investigate the relation between delta wave notching time (DwNt) and accessory pathway location in patients with Wolff-Parkinson-White (WPW) syndrome.

Methods: The retrospective study included 149 WPW patients who underwent ablation therapy. DwNt was defined as the duration between the initial point of QRS and the notching in the delta wave. DwNt was divided by QRS duration to obtain the delta wave index (Dwi).

Results: Patients with left-sided accessory pathway (AP) had significantly higher DwNt (p < 0.001) and Dwi (p = 0.027) values. The R wave voltage in lead I (p = 0.037) and S wave voltage in lead V1 (p = 0.005) values were significantly higher in patients with right-sided AP compared to patients with left-sided AP. When 27 ms was taken as the DwNt cut-off value, higher durations determined the left-sided AP location with a sensitivity of 91% and a negative predictive value of 91.4%. Dwi cutoff values ≥ 0.29 were accepted to indicate a left-sided AP location with a sensitivity of 91.2% and a NPV of 91.4%.

Conclusions: WPW patients with left-sided AP have longer DwNt values than patients with right-sided AP.