title: Impact of earliest activation site location in the septal right ventricular outflow tract for identification of left vs right outflow tract origin of idiopathic ventricular arrhythmias.
abstract: BACKGROUND
  The earliest activation site (EAS) location in the septal right ventricular outflow tract (RVOT) could be an additional mapping data predictor of left ventricular outflow tract (LVOT) vs RVOT origin of idiopathic ventricular arrhythmias (VAs).
  
  
  OBJECTIVE
  The purpose of this study was to assess the impact of EAS location in predicting LVOT vs RVOT origin.
  
  
  METHODS
  Macroscopic and histologic study was performed in 12 postmortem hearts. Electroanatomic maps (EAMs) from 37 patients with outflow tract (OT) VA with the EAS in the septal RVOT were analyzed. Pulmonary valve (PV) was defined by voltage scanning after validation of voltage thresholds by image integration. EAM measurements were correlated with those of macroscopic/histologic study.
  
  
  RESULTS
  A cutoff value of 1.9 mV discriminated between subvalvular and supravalvular positions (90% sensitivity, 96% specificity). EAS ≥1 cm below PV excluded RVOT site of origin (SOO). According to anatomic findings (distance PV-left coronary cusp = 5 ± 3 vs PV-right coronary cusp = 11 ± 5 mm), EAS-PV distance was significantly shorter in VAs arising from left coronary cusp than from the other LVOT locations (4.2 ± 5.4 mm vs 9.2 ± 7 mm; P = .034). The 10-ms isochronal longitudinal/perpendicular diameter ratio was higher in the RVOT vs the LVOT SOO group (1.97 ± 1.2 vs 0.79 ± 0.49; P = .001). An algorithm based on EAS-PV distance and the 10-ms isochronal longitudinal/perpendicular diameter ratio predicted LVOT SOO with 91% sensitivity and 100% specificity.
  
  
  CONCLUSIONS
  An algorithm based on the EAS-PV distance and the 10-ms isochronal longitudinal/perpendicular diameter ratio accurately predicts LVOT vs RVOT SOO in outflow tract VAs with EAS in the septal RVOT.
authors.affiliation: Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Catalonia, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Acosta
authors.affiliation: Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Catalonia, Spain.
authors.forename: Diego
authors.initials: D
authors.lastname: Penela
authors.affiliation: Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Catalonia, Spain.
authors.forename: Csaba
authors.initials: C
authors.lastname: Herczku
authors.affiliation: Department of Anatomy and Cell Biology, Faculty of Medicine, University of Extremadura, Badajoz, Spain.
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Macías
authors.affiliation: Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Catalonia, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Andreu
authors.affiliation: Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Catalonia, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Fernández-Armenta
authors.affiliation: Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Catalonia, Spain.
authors.forename: Laura
authors.initials: L
authors.lastname: Cipolletta
authors.affiliation: Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Catalonia, Spain.
authors.forename: Andrés
authors.initials: A
authors.lastname: Díaz
authors.affiliation: Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Catalonia, Spain.
authors.forename: Viatcheslav
authors.initials: V
authors.lastname: Korshunov
authors.affiliation: Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Catalonia, Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: Brugada
authors.affiliation: Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Catalonia, Spain.
authors.forename: Lluis
authors.initials: L
authors.lastname: Mont
authors.affiliation: Department of Anatomy and Cell Biology, Faculty of Medicine, University of Extremadura, Badajoz, Spain.
authors.forename: Jose A
authors.initials: JA
authors.lastname: Cabrera
authors.affiliation: Department of Anatomy and Cell Biology, Faculty of Medicine, University of Extremadura, Badajoz, Spain.
authors.forename: Damián
authors.initials: D
authors.lastname: Sánchez-Quintana
authors.affiliation: Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Catalonia, Spain. Electronic address: berruezo@clinic.ub.es.
authors.forename: Antonio
authors.initials: A
authors.lastname: Berruezo
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D018780:Body Surface Potential Mapping / Q000379:methods; D017115:Catheter Ablation / Q000379:methods; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006352:Heart Ventricles / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008953:Models, Anatomic; D011664:Pulmonary Valve / Q000473:pathology / Q000503:physiopathology; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D054088:Ventricular Septum / Q000473:pathology / Q000503:physiopathology
keywords: Idiopathic ventricular tachycardia; Left ventricular outflow tract; Pulmonary valve; Right ventricular outflow tract; Site of origin