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

Area of Science:

• Cardiology
• Electrophysiology
• Medical Diagnostics

Background:

• Wolff-Parkinson-White (WPW) syndrome and fasciculoventricular pathway (FVP) share electrocardiographic delta wave characteristics, complicating differential diagnosis.
• WPW type B with narrow QRS complexes can mimic FVP, necessitating improved diagnostic methods.

Purpose of the Study:

• To evaluate the QRS-T angle's effectiveness in differentiating WPW syndrome from FVP.
• To determine a specific QRS-T angle cut-off value for distinguishing between WPW syndrome and FVP.

Main Methods:

• Retrospective analysis of 40 WPW syndrome and 54 FVP cases diagnosed between 2007 and 2023.
• Exclusion criteria included WPW type A, wide QRS, intermittent WPW, cardiac abnormalities, and recent symptoms.
• Comparison of QRS-T angles between the WPW and FVP groups using receiver operating characteristic (ROC) curve analysis.

Main Results:

• The mean QRS-T angle was significantly larger in the WPW group (45.7 ± 46.3°) compared to the FVP group (17.8 ± 13.9°, p < 0.001).
• An optimal QRS-T angle cut-off of 22° achieved 65.0% sensitivity and 72.6% specificity for differentiating WPW from FVP.
• All cases with a QRS-T angle >65° were identified as WPW syndrome.

Conclusions:

• The QRS-T angle is a valuable tool for differentiating WPW syndrome from FVP.
• A QRS-T angle of 22° serves as a potential threshold for distinguishing these two conditions.