Referenced Criteria
The V2 transition ratio: a new electrocardiographic criterion for distinguishing left from right ventricular outflow tract tachycardia origin
Circulation: Arrhythmia and Electrophysiology · 2011 · PMID 21616286
Developed for outflow-tract ventricular arrhythmias with a V3 precordial transition. A ratio at or above 0.60 favored LVOT origin in the study population.
A novel electrocardiographic criterion for differentiating a left from right ventricular outflow tract tachycardia origin: the V2S/V3R index
Journal of Cardiovascular Electrophysiology · 2014 · PMID 24612087
DOI 10.1111/jce.12392
Studied in LBBB-pattern, inferior-axis outflow-tract arrhythmias. An index at or below 1.5 favored LVOT origin.
Idiopathic epicardial left ventricular tachycardia originating remote from the sinus of Valsalva
Circulation · 2006 · PMID 16567566
A maximum deflection index at or above 0.55 identified an epicardial-origin feature in the original study population.
Evidence Boundary
Thresholds were derived in selected cohorts and may not generalize to all substrates, baseline conduction patterns, lead placements, or recording conditions.