title: Electroanatomic Correlates of Depolarization Abnormalities in Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy.
abstract: BACKGROUND
  Epsilon waves and other depolarization abnormalities in the right precordial leads are thought to represent delayed activation of the right ventricular outflow tract in arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C). However, no study has directly correlated cardiac electrical activation with the surface ECG findings in ARVD/C.
  
  
  RESULTS
  Thirty ARVD/C patients (mean age 32.7 ± 11.2 years, 16 men) underwent endocardial and epicardial electroanatomical activation mapping in sinus rhythm. Twelve-lead ECGs were classified into 5 patterns: (1) normal QRS (11 patients); (2) terminal activation delay (TAD) (3 patients); (3) incomplete right bundle branch block (IRBBB) (5 patients); (4) epsilon wave (5 patients); (5) complete right bundle branch block (CRBBB) (6 patients). Timing of local ventricular activation and extent of scar was then correlated with surface QRS. Earliest endocardial and epicardial RV activation occurred on the mid anteroseptal wall in all patients despite the CRBBB pattern on ECG. Total RV activation times increased from normal QRS to prolonged TAD, IRBBB, epsilon wave, and CRBBB, respectively (103.9 ± 5.6, 116.3 ± 6.5, 117.8 ± 2.7, 146.4 ± 16.3, and 154.3 ± 6.3, respectively, P < 0.05). The total epicardial scar area (cm(2) ) was similar among the different ECG patterns. Median endocardial scar burden was significantly higher in patients with epsilon waves even compared with patients with CRBBB (34.3 vs. 11.3 cm(2) , P < 0.01). Timing of epsilon wave corresponded to activation of the subtricuspid region in all patients.
  
  
  CONCLUSIONS
  We found that epsilon waves are often associated with severe conduction delay and extensive endocardial scarring in addition to epicardial disease. The timing of epsilon waves on surface ECG correlated with electrical activation of the sub-tricuspid region.
authors.affiliation: Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: Tanyanan
authors.initials: T
authors.lastname: Tanawuttiwat
authors.affiliation: Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.|Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Anneline S J M
authors.initials: AS
authors.lastname: Te Riele
authors.affiliation: Section of Cardiac Electrophysiology, Cardiovascular Institute, Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA.
authors.forename: Binu
authors.initials: B
authors.lastname: Philips
authors.affiliation: Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: Cynthia A
authors.initials: CA
authors.lastname: James
authors.affiliation: Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: Brittney
authors.initials: B
authors.lastname: Murray
authors.affiliation: Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: Crystal
authors.initials: C
authors.lastname: Tichnell
authors.affiliation: Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: Abhishek C
authors.initials: AC
authors.lastname: Sawant
authors.affiliation: Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: Hugh
authors.initials: H
authors.lastname: Calkins
authors.affiliation: Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: Harikrishna
authors.initials: H
authors.lastname: Tandri
mesh_terms: D000328:Adult; D019571:Arrhythmogenic Right Ventricular Dysplasia / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology*; D002037:Bundle-Branch Block / Q000175:diagnosis* / Q000503:physiopathology*; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006329:Heart Conduction System / Q000002:abnormalities / Q000503:physiopathology*; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: arrhythmogenic right ventricular; catheter ablation; dysplasia/cardiomyopathy; epicardial mapping; epsilon wave; right bundle branch block