title: Ventricular Tachycardia and Early Fibrillation in Patients With Brugada Syndrome and Ischemic Cardiomyopathy Show Predictable Frequency-Phase Properties on the Precordial ECG Consistent With the Respective Arrhythmogenic Substrate.
abstract: BACKGROUND
  Ventricular fibrillation (VF) has been proposed to be maintained by localized high-frequency sources. We tested whether spectral-phase analysis of the precordial ECG enabled identification of periodic activation patterns generated by such sources.
  
  
  RESULTS
  Precordial ECGs were recorded from 15 ischemic cardiomyopathy and 15 Brugada syndrome (type 1 ECG) patients during induced VF and analyzed in the frequency-phase domain. Despite temporal variability, induced VF episodes lasting 19.6±7.9 s displayed distinctly high power at a common frequency (shared frequency, 5.7±1.1 Hz) in all leads about half of the time. In patients with Brugada syndrome, phase analysis of shared frequency showed a V1-V6 sequence as would be expected from patients displaying a type 1 ECG pattern (P<0.001). Hilbert-based phases confirmed that the most stable sequence over the whole VF duration was V1-V6. Analysis of shared frequency in ischemic cardiomyopathy patients with anteroseptal (n=4), apical (n=3), and inferolateral (n=4) myocardial infarction displayed a sequence starting at V1-V2, V3-V4, and V5-V6, respectively, consistent with an activation origin at the scar location (P=0.005). Sequences correlated with the Hilbert-based phase analysis (P<0.001). Posterior infarction (n=4) displayed no specific sequence. On paired comparison, phase sequences during monomorphic ventricular tachycardia correlated moderately with VF (P<0.001). Moreover, there was a dominant frequency gradient from precordial leads facing the scar region to the contralateral leads (5.8±0.8 versus 5.4±1.1 Hz; P=0.004).
  
  
  CONCLUSIONS
  Noninvasive analysis of ventricular tachycardia and early VF in patients with Brugada syndrome and ischemic cardiomyopathy shows a predictable sequence in the frequency-phase domain, consistent with anatomic location of the arrhythmogenic substrate.
authors.affiliation: From the Arrhythmia Unit, Hospital Universitario Central de Asturias, Oviedo, Spain (D.C., J.R.); Center for Arrhythmia Research, University of Michigan, Ann Arbor (J.J., O.B.); Arrhythmia Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain (F.A., P.Á., Á.A.); Centro de Investigación e Innovación en Bioingeniería, Ci2B, Universitat Politècnica de Valencia, Valencia, Spain (J.S., L.M., A.F.); Arrhythmia Unit, Hospital Río Hortega de Valladolid and Universitario de Burgos, Valladolid-Burgos, Spain (B.H., J.G.-F.); Universitat de Valencia, Valencia, Spain (R.S.); and Department of Statistics, Hospital Universitario Central de Asturias, Oviedo, Spain (P.M.-C.).
authors.forename: David
authors.initials: D
authors.lastname: Calvo
authors.affiliation: From the Arrhythmia Unit, Hospital Universitario Central de Asturias, Oviedo, Spain (D.C., J.R.); Center for Arrhythmia Research, University of Michigan, Ann Arbor (J.J., O.B.); Arrhythmia Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain (F.A., P.Á., Á.A.); Centro de Investigación e Innovación en Bioingeniería, Ci2B, Universitat Politècnica de Valencia, Valencia, Spain (J.S., L.M., A.F.); Arrhythmia Unit, Hospital Río Hortega de Valladolid and Universitario de Burgos, Valladolid-Burgos, Spain (B.H., J.G.-F.); Universitat de Valencia, Valencia, Spain (R.S.); and Department of Statistics, Hospital Universitario Central de Asturias, Oviedo, Spain (P.M.-C.).
authors.forename: Felipe
authors.initials: F
authors.lastname: Atienza
authors.affiliation: From the Arrhythmia Unit, Hospital Universitario Central de Asturias, Oviedo, Spain (D.C., J.R.); Center for Arrhythmia Research, University of Michigan, Ann Arbor (J.J., O.B.); Arrhythmia Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain (F.A., P.Á., Á.A.); Centro de Investigación e Innovación en Bioingeniería, Ci2B, Universitat Politècnica de Valencia, Valencia, Spain (J.S., L.M., A.F.); Arrhythmia Unit, Hospital Río Hortega de Valladolid and Universitario de Burgos, Valladolid-Burgos, Spain (B.H., J.G.-F.); Universitat de Valencia, Valencia, Spain (R.S.); and Department of Statistics, Hospital Universitario Central de Asturias, Oviedo, Spain (P.M.-C.).
authors.forename: Javier
authors.initials: J
authors.lastname: Saiz
authors.affiliation: From the Arrhythmia Unit, Hospital Universitario Central de Asturias, Oviedo, Spain (D.C., J.R.); Center for Arrhythmia Research, University of Michigan, Ann Arbor (J.J., O.B.); Arrhythmia Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain (F.A., P.Á., Á.A.); Centro de Investigación e Innovación en Bioingeniería, Ci2B, Universitat Politècnica de Valencia, Valencia, Spain (J.S., L.M., A.F.); Arrhythmia Unit, Hospital Río Hortega de Valladolid and Universitario de Burgos, Valladolid-Burgos, Spain (B.H., J.G.-F.); Universitat de Valencia, Valencia, Spain (R.S.); and Department of Statistics, Hospital Universitario Central de Asturias, Oviedo, Spain (P.M.-C.).
authors.forename: Laura
authors.initials: L
authors.lastname: Martínez
authors.affiliation: From the Arrhythmia Unit, Hospital Universitario Central de Asturias, Oviedo, Spain (D.C., J.R.); Center for Arrhythmia Research, University of Michigan, Ann Arbor (J.J., O.B.); Arrhythmia Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain (F.A., P.Á., Á.A.); Centro de Investigación e Innovación en Bioingeniería, Ci2B, Universitat Politècnica de Valencia, Valencia, Spain (J.S., L.M., A.F.); Arrhythmia Unit, Hospital Río Hortega de Valladolid and Universitario de Burgos, Valladolid-Burgos, Spain (B.H., J.G.-F.); Universitat de Valencia, Valencia, Spain (R.S.); and Department of Statistics, Hospital Universitario Central de Asturias, Oviedo, Spain (P.M.-C.).
authors.forename: Pablo
authors.initials: P
authors.lastname: Ávila
authors.affiliation: From the Arrhythmia Unit, Hospital Universitario Central de Asturias, Oviedo, Spain (D.C., J.R.); Center for Arrhythmia Research, University of Michigan, Ann Arbor (J.J., O.B.); Arrhythmia Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain (F.A., P.Á., Á.A.); Centro de Investigación e Innovación en Bioingeniería, Ci2B, Universitat Politècnica de Valencia, Valencia, Spain (J.S., L.M., A.F.); Arrhythmia Unit, Hospital Río Hortega de Valladolid and Universitario de Burgos, Valladolid-Burgos, Spain (B.H., J.G.-F.); Universitat de Valencia, Valencia, Spain (R.S.); and Department of Statistics, Hospital Universitario Central de Asturias, Oviedo, Spain (P.M.-C.).
authors.forename: José
authors.initials: J
authors.lastname: Rubín
authors.affiliation: From the Arrhythmia Unit, Hospital Universitario Central de Asturias, Oviedo, Spain (D.C., J.R.); Center for Arrhythmia Research, University of Michigan, Ann Arbor (J.J., O.B.); Arrhythmia Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain (F.A., P.Á., Á.A.); Centro de Investigación e Innovación en Bioingeniería, Ci2B, Universitat Politècnica de Valencia, Valencia, Spain (J.S., L.M., A.F.); Arrhythmia Unit, Hospital Río Hortega de Valladolid and Universitario de Burgos, Valladolid-Burgos, Spain (B.H., J.G.-F.); Universitat de Valencia, Valencia, Spain (R.S.); and Department of Statistics, Hospital Universitario Central de Asturias, Oviedo, Spain (P.M.-C.).
authors.forename: Benito
authors.initials: B
authors.lastname: Herreros
authors.affiliation: From the Arrhythmia Unit, Hospital Universitario Central de Asturias, Oviedo, Spain (D.C., J.R.); Center for Arrhythmia Research, University of Michigan, Ann Arbor (J.J., O.B.); Arrhythmia Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain (F.A., P.Á., Á.A.); Centro de Investigación e Innovación en Bioingeniería, Ci2B, Universitat Politècnica de Valencia, Valencia, Spain (J.S., L.M., A.F.); Arrhythmia Unit, Hospital Río Hortega de Valladolid and Universitario de Burgos, Valladolid-Burgos, Spain (B.H., J.G.-F.); Universitat de Valencia, Valencia, Spain (R.S.); and Department of Statistics, Hospital Universitario Central de Asturias, Oviedo, Spain (P.M.-C.).
authors.forename: Ángel
authors.initials: Á
authors.lastname: Arenal
authors.affiliation: From the Arrhythmia Unit, Hospital Universitario Central de Asturias, Oviedo, Spain (D.C., J.R.); Center for Arrhythmia Research, University of Michigan, Ann Arbor (J.J., O.B.); Arrhythmia Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain (F.A., P.Á., Á.A.); Centro de Investigación e Innovación en Bioingeniería, Ci2B, Universitat Politècnica de Valencia, Valencia, Spain (J.S., L.M., A.F.); Arrhythmia Unit, Hospital Río Hortega de Valladolid and Universitario de Burgos, Valladolid-Burgos, Spain (B.H., J.G.-F.); Universitat de Valencia, Valencia, Spain (R.S.); and Department of Statistics, Hospital Universitario Central de Asturias, Oviedo, Spain (P.M.-C.).
authors.forename: Javier
authors.initials: J
authors.lastname: García-Fernández
authors.affiliation: From the Arrhythmia Unit, Hospital Universitario Central de Asturias, Oviedo, Spain (D.C., J.R.); Center for Arrhythmia Research, University of Michigan, Ann Arbor (J.J., O.B.); Arrhythmia Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain (F.A., P.Á., Á.A.); Centro de Investigación e Innovación en Bioingeniería, Ci2B, Universitat Politècnica de Valencia, Valencia, Spain (J.S., L.M., A.F.); Arrhythmia Unit, Hospital Río Hortega de Valladolid and Universitario de Burgos, Valladolid-Burgos, Spain (B.H., J.G.-F.); Universitat de Valencia, Valencia, Spain (R.S.); and Department of Statistics, Hospital Universitario Central de Asturias, Oviedo, Spain (P.M.-C.).
authors.forename: Ana
authors.initials: A
authors.lastname: Ferrer
authors.affiliation: From the Arrhythmia Unit, Hospital Universitario Central de Asturias, Oviedo, Spain (D.C., J.R.); Center for Arrhythmia Research, University of Michigan, Ann Arbor (J.J., O.B.); Arrhythmia Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain (F.A., P.Á., Á.A.); Centro de Investigación e Innovación en Bioingeniería, Ci2B, Universitat Politècnica de Valencia, Valencia, Spain (J.S., L.M., A.F.); Arrhythmia Unit, Hospital Río Hortega de Valladolid and Universitario de Burgos, Valladolid-Burgos, Spain (B.H., J.G.-F.); Universitat de Valencia, Valencia, Spain (R.S.); and Department of Statistics, Hospital Universitario Central de Asturias, Oviedo, Spain (P.M.-C.).
authors.forename: Rafael
authors.initials: R
authors.lastname: Sebastián
authors.affiliation: From the Arrhythmia Unit, Hospital Universitario Central de Asturias, Oviedo, Spain (D.C., J.R.); Center for Arrhythmia Research, University of Michigan, Ann Arbor (J.J., O.B.); Arrhythmia Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain (F.A., P.Á., Á.A.); Centro de Investigación e Innovación en Bioingeniería, Ci2B, Universitat Politècnica de Valencia, Valencia, Spain (J.S., L.M., A.F.); Arrhythmia Unit, Hospital Río Hortega de Valladolid and Universitario de Burgos, Valladolid-Burgos, Spain (B.H., J.G.-F.); Universitat de Valencia, Valencia, Spain (R.S.); and Department of Statistics, Hospital Universitario Central de Asturias, Oviedo, Spain (P.M.-C.).
authors.forename: Pablo
authors.initials: P
authors.lastname: Martínez-Camblor
authors.affiliation: From the Arrhythmia Unit, Hospital Universitario Central de Asturias, Oviedo, Spain (D.C., J.R.); Center for Arrhythmia Research, University of Michigan, Ann Arbor (J.J., O.B.); Arrhythmia Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain (F.A., P.Á., Á.A.); Centro de Investigación e Innovación en Bioingeniería, Ci2B, Universitat Politècnica de Valencia, Valencia, Spain (J.S., L.M., A.F.); Arrhythmia Unit, Hospital Río Hortega de Valladolid and Universitario de Burgos, Valladolid-Burgos, Spain (B.H., J.G.-F.); Universitat de Valencia, Valencia, Spain (R.S.); and Department of Statistics, Hospital Universitario Central de Asturias, Oviedo, Spain (P.M.-C.).
authors.forename: José
authors.initials: J
authors.lastname: Jalife
authors.affiliation: From the Arrhythmia Unit, Hospital Universitario Central de Asturias, Oviedo, Spain (D.C., J.R.); Center for Arrhythmia Research, University of Michigan, Ann Arbor (J.J., O.B.); Arrhythmia Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain (F.A., P.Á., Á.A.); Centro de Investigación e Innovación en Bioingeniería, Ci2B, Universitat Politècnica de Valencia, Valencia, Spain (J.S., L.M., A.F.); Arrhythmia Unit, Hospital Río Hortega de Valladolid and Universitario de Burgos, Valladolid-Burgos, Spain (B.H., J.G.-F.); Universitat de Valencia, Valencia, Spain (R.S.); and Department of Statistics, Hospital Universitario Central de Asturias, Oviedo, Spain (P.M.-C.). oberen@umich.edu.
authors.forename: Omer
authors.initials: O
authors.lastname: Berenfeld
mesh_terms: D000328:Adult; D000368:Aged; D053840:Brugada Syndrome / Q000503:physiopathology*; D009202:Cardiomyopathies / Q000503:physiopathology*; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D006801:Humans; D008875:Middle Aged; D017180:Tachycardia, Ventricular / Q000503:physiopathology*; D014693:Ventricular Fibrillation / Q000503:physiopathology*
keywords: Brugada syndrome; electrocardiography; myocardial infarction; tachycardia, ventricular; ventricular fibrillation