Distinguishing Wolff-Parkinson-White Syndrome From Fasciculoventricular Pathway Using QRS-T Angle Analysis

Wolff-Parkinson-White (WPW) syndrome and fasciculoventricular pathway (FVP) present electrocardiographic manifestations characterized by delta waves, differentiating these two is challenging. Specifically, WPW type B with QRS width ≤120 ms, resembles typical FVP features. Because of the presence of repolarization abnormalities in WPW syndrome, our hypothesis centered on the potential utility of the QRS-T angle for distinguishing WPW syndrome from FVP. To determine the discriminative value of the QRS-T angle for delineating WPW syndrome from FVP.

We included cases of WPW syndrome treated with catheter ablation and FVP diagnosed via adenosine triphosphate administration between 2007 and 2023. We excluded cases with WPW type A, QRS width >120 ms, intermittent WPW, congenital heart disease or myocardial damage, ablation history, tachycardia, palpitations within 3 months, and WPW syndrome featuring an accessory pathway on the left lateral wall. Eventually, we identified 40 and 54 patients from the WPW and FVP groups, respectively. The QRS-T angle was compared between the WPW and FVP cohorts.

The QRS-T angle in the WPW group was significantly larger than in the FVP group (45.7 ± 46.3° vs. 17.8 ± 13.9°, p < 0.001). Receiver operating characteristic curve analysis with a sensitivity and specificity of 65.0% and 72.6%, respectively, demonstrated that the optimal cut-off value for the QRS-T angle was 22° for distinguishing WPW from FVP. Remarkably, all cases with a QRS-T angle >65° were within the WPW group.

The QRS-T angle can offer promising utility in differentiating WPW syndrome from FVP.