AIM To propose an ECG diagnostic method to distinguish ventricular arrhythmias originating from HIS bundle area (HIS), posterior right ventricular outflow tract (pRVOT) and anterolateral of tricuspid annulus (TA-AL).
METHODS Seventy-five consecutive patients with ventricular arrhythmias (VA) that were successfully ablated from HIS (n=18), pRVOT (n=42) or TA-AL (n=15) were enrolled in this study. The measurements of ECG parameters showed highest diagnostic performance were used to develop the diagnostic criterion.
RESULTS Among the ECG parameters, R wave amplitude in lead Ⅰ and QRS duration were found to have the best diagnostic performance in distinguishing these different origins. The best ECG identification method was the combination of R wave amplitude in lead Ⅰ and QRS duration: HIS, R wave amplitude in lead Ⅰ>0.49 mV and QRS duration≤125.5 ms (sensitivity 72.2%, specificity 100%); pRVOT, R-wave amplitude in lead Ⅰ≤0.49 mV and QRS duration >125.5 ms (sensitivity 88.1%, specificity 81.8%) and TA-AL, R-wave amplitude in lead I > 0.49 mV and QRS duration >125.5 ms (sensitivity 66.7%, specificity 95.0%). The overall accuracy of these diagnostic criteria in determining the site of origin of VA was 88.9%.
CONCLUSION The VAs originating near HIS usually show positive R wave in lead Ⅰ and short QRS duration. The combined application of R wave amplitude in lead Ⅰ and QRS duration can be used to distinguish VAs originating from HIS, pRVOT or TA-AL.