The RV 1 -V 3 transition ratio: A novel electrocardiographic criterion for the differentiation of right versus left outflow tract premature ventricular complexes.

Background: Several electrocardiographic (ECG) indices have been proposed to predict the origin of premature ventricular complexes (PVCs) with precordial transition in lead V3 . However, the accuracy of these algorithms is limited.

Objectives: We sought to evaluate a new ECG criterion differentiating the origin of outflow tract with precordial transition in lead V3 .

Methods: We included in our study patients exhibiting outflow tract PVCs with precordial transition in lead V3 referred for ablation. We analyzed a novel new ECG criterion, RV1 -V3 transition ratio, for distinguishing right from left idiopathic outflow tract PVCs with precordial transition in lead V3 . The RV1 -V3 transition ratio was defined as (RV1+RV2+RV3) PVC / (RV1+RV2+RV3) SR (sinus rhythm).

Results: We included 58 patients in our study. The ratio was lower for right ventricular outflow tract origins than left ventricular outflow tract (LVOT) origins (median [interquartile range], 0.6953 [0.4818-1.0724] vs 1.5219 [1.1582-2.4313], P < .001). Receiver operating characteristic analysis revealed an area under the curve of 0.856 for the ratio, and a cut-off value of ≥0.9 predicting LVOT origin with 94% sensitivity and 73% specificity. This ratio was superior to any previously proposed ECG criterion for differentiating right from left outflow tract PVCs.

Conclusion: The RV1 -V3 transition ratio is a simple and accurate novel ECG criterion for distinguishing right from left idiopathic outflow tract PVCs with precordial transition in lead V3 .