The RV1-V3 transition ratio: A novel electrocardiographic criterion for the differentiation of right versus left outflow tract premature ventricular complexes

Figures

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  Figure 1. The RV1-V3 transition ratio [(RV1+RV2+RV3)PVC / (RV1+RV2+RV3)SR] was defined as the sum of R-wave amplitude in leads V1, V2, and V3 during premature ventricular contraction divided by the sum of R-wave amplitude in leads V1, V2, and V3 during sinus rhythm.

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  Figure 2. The RV1-V3 transition ratio [(RV1+RV2+RV3)PVC / (RV1+RV2+RV3)SR] was significantly lower for right ventricular outflow tract origins than left ventricular outflow tract origins.

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  Figure 3. The RV1-V3 transition ratio was compared with 3 already known electrocardiography indices: the V2 transition ratio, the V2S/V3R index, and the V1-V3 transition index. The novel ratio displayed an area under the curve (AUC) of 0.856 with a cut-off value of ≥0.9 predicting a left ventricular outflow tract (LVOT) origin with 94% sensitivity and 73% specificity. The RV1-V3 transition ratio was significantly lower for right ventricular outflow tract (RVOT) origins than LVOT origins (median [interquartile range (IQR)], 0.6953 [0.4818–1.0724] vs 1.5219 [1.1582–2.4313], P < .001). The V2 transition ratio had an AUC of 0.818, with a cut-off value of ≥0.60 predicting LVOT origin with 81% sensitivity and 64% specificity. The V2 transition ratio was significantly lower for RVOT origins than LVOT origins (median [IQR], 0.4392 [0.2587–0.7795] vs 1.2429 [0.6435–1.7757], P < .001). The V2S/V3R index had an AUC of 0.8283, with a cut-off value of ≤1.5 predicting LVOT origin with 75% sensitivity and 82% specificity. The V2S/V3R index was significantly higher for RVOT origins than LVOT origins (median [IQR], 2.1591 [1.7134–2.9135] vs 1.0426 [0.7290–1.5516], P < .001]. The V1-V3 transition index had…

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  Figure 4. A: An electroanatomical map in posteroanterior (PA) projection with clipped view showing the positions of the left coronary cusp (LCC) and endocardial left ventricular outflow tract (LVOT) regions. Activation mapping delineates the site of origin of premature ventricular contraction (PVC) at the LCC. Surface electrocardiogram (12 leads), distal bipolar (MAP 1–2), intracardiac electrograms recorded from the early site are shown. Local activation precedes QRS by 30 ms. Our novel RV1-V3 transition ratio was 4.07 (≥0.9), predicting an LVOT origin. V2 transition ratio was 4.18, predicting an LVOT origin; V2S/V3R index was 0.61 predicting an LVOT origin; and V1-V3 transition index was -9.6, predicting an LVOT origin. B: An electroanatomical map in left anterior oblique projection with clipped view showing the positions of the LCC, great cardiac vein (GCV), and right ventricular outflow tract (RVOT) regions. Activation mapping delineates the site of origin of the PVC at the right coronary cusp (RCC)-LCC. Surface electrocardiogram (12 leads), distal bipolar (MAP 1–2), intracardiac electrograms recorded from the earliest site are shown. Local activation precedes QRS by 20 ms. We…