To compare the clinical value of opposing QRS complex on limb leads (OQL) criteria and ventricular tachycardia (VT) score in identifying pre-excited tachycardia.

Twelve-lead electrocardiograph results were obtained from 18 patients at pre-excited tachycardia attacking stage who were diagnosed by electrophysiology. Pre-excited tachycardia was scored based on the OQL criteria and the VT score. The specificities of OQL criteria and VT score (≥2 points and ≥3 points) in identifying pre-excited tachycardia were compared by chi-square test. The specificities of the two modalities in different pre-excitation types and different bypass positions were analyzed.

The specificity of OQL criteria for patients with pre-excited tachycardia was 38.89%. The specificity of VT score (≥2 points and ≥3 points) for patients with pre-excited tachycardia were 55.56% and 100.00%, respectively. Comparing the results of the OQL criteria with the VT score ≥2 points, there was no statistical difference in the two groups (P＞0.05). Comparing the results of the OQL criteria with the VT score ≥3 points, the difference was statistically significant (P＜0.05). There was no significant difference in the specificities of the two modalities in different pre-excitation types and different bypass positions (P＞0.05).

VT score ≥3 points can completely identify pre-excited tachycardia and VT. The OQL criteria and VT score ≥2 points cannot completely distinguish pre-excited tachycardia from VT.