Purpose: We aimed to investigate the predictive value of coupling interval variability (ΔCI) in determining the origin of idiopathic outflow tract ventricular tachycardia (OTVT) with V3 transition.
Methods: We reviewed data from 126 patients who underwent catheter ablation of OTVT between 2015 and 2018 at our institution. We identified 32 patients of successful OTVT ablation with a precordial transition at V3 derivation. The ΔCI (maximum - minimum CI) was measured.
Results: CI variability was significantly smaller for right ventricular (RV) OT than left ventricular (LV) OT premature ventricular contractions (PVCs) (p = 0.004). In multivariate analysis, including QRS duration, R-wave duration in lead V1, R-wave amplitude in V1, PVC burden, and ΔCI, ΔCI was the only independent predictor of PVC origin (OR 0.963, 95% CI, 0.939-0.988, p < 0.001). A CI variability ≥ 30 predicted a PVC from LVOT origin with a sensitivity of 83% and specificity of 89%. ΔCI was compared with other previously proposed ECG criteria used to differentiate LVOT from RVOT PVCs. ΔCI exhibited a greater area under the curve (AUC) (0.867) than the other ECG criteria. A ΔCI ≥ 30 ms exhibited a high sensitivity of 89% and a specificity of 83%.
Conclusions: ΔCI is outperformed other ECG criteria to differentiate LVOT from RVOT PVCs, and this parameter may be useful for planning the ablation strategy.
Keywords: Coupling interval; Electrocardiogram; Premature ventricular contractions; V3 transition.