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The RV1-V3 transition ratio: A novel electrocardiographic criterion for the differentiation of right versus left
Michael Efremidis1,2, Konstantinos Vlachos1,2, Maria Kyriakopoulou3,4
1Onassis Cardiac Surgery Centre, Athens, Greece.
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.
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An electrocardiogram (ECG) is a diagnostic tool for identifying cardiac conditions such as arrhythmias, conduction abnormalities, and myocardial ischemia.
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An electrocardiogram (ECG) visualizes the heart's electrical activity by tracing the electrical movement associated with each heartbeat on a graph or monitor. As the heart beats, an electrical wave passes through it, correlating with the cardiac cycle events.
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