Identification Of The Premature Ventricular Contractions Originated From The Outflow Tract By Electrocardiogram

Objective: To explore the ECG characteristics of premature ventricular contraction(PVC)originates from out flow tract and their location value for out flow tract originated PVC.Methods: A retrospective analysis was made in 60 cases of PVCs patients originating from ventricular out flow tract who underwent successful catheter ablation.We measured transitional zone,transitional zone index,amplitude and duration index of R wave in V2 lead,then we discussed the location value for out flow tract originated PVC and and calculated the specificity and sensitivities.Results: There was no significant difference in general circumstances between 48 RVOT-PVC and 12 LVOT-PVC paitients.Transitional zone of LVOT-PVC is earlier than RVOT-PVC,and it is most located between V1 and V3.There was significant difference in transitional zone,transitional zone index,amplitude and duration index of R wave in V2 lead between 48RVOT-PVC and 12 LVOT-PVC paitients.According to ROC,the sensitivity and specificity of transitional zone index are 83.3% and 89.6%;the sensitivity and specificity of transitional zone index and duration index combined diagnosis are 97.3% and 79.2%;the sensitivity and specificity of all are 98.6%and 91.7%.Conclusion : Transitional zone,transitional zone index,amplitude and duration index of R wave in V2 lead played important roles in identifying theorigin sites of PVC-OVT.