title: Transient and rapid QRS-widening associated with a J-wave pattern predicts impending ventricular fibrillation in experimental myocardial infarction.
abstract: BACKGROUND
  Certain types of the early repolarization phenomenon, previously considered to be benign, have been reported to be associated with ventricular fibrillation (VF), both in population-based studies and in the myocardial infarction (MI) settings.
  
  
  OBJECTIVE
  To analyze whether QRS widening and appearance of a J-wave pattern in experimental MI settings is predictive of VF.
  
  
  METHODS
  MI was induced in 32 pigs by 40-minute inflation of an angioplasty balloon in the left descending artery, and electrocardiogram was continuously recorded. Multilead QRS boundaries were computed, and QRS duration was calculated on a beat-to-beat basis during the occlusion period for each pig. An association between QRS widening and subsequent VF was studied using receiver operating characteristic curve analysis. Electrocardiograms at maximum QRS duration were reviewed for the presence of a J-wave pattern.
  
  
  RESULTS
  Sixteen animals had VF episodes during the occlusion period. Two peaks of QRS widening were found in all animals: the first peak immediately on left descending artery occlusion and the second peak 19.1 ± 4.0 minutes later. The magnitude of changes in the QRS width over time had significant interindividual differences. A QRS widening of ≥28 ms during a 3-minute time window was observed in 14 animals and predicted impending VF (selectivity 80%, specificity 73%, positive predictive value 57%, and negative predictive value 89%; P = .008). In 10 of 14 (71%) pigs, a J-wave pattern appeared at maximal QRS duration. The appearance of a J-wave pattern predicted VF with selectivity 80%, specificity 68%, positive predictive value 53%, and negative predictive value 88% (P = .02).
  
  
  CONCLUSIONS
  Transient QRS widening, commonly associated with a J-wave pattern, appears to predict impending VF in acute ischemia settings and motivates further clinical studies for monitoring immediate risk of VF in MI.
authors.affiliation: Department of Cardiology, Lund University, Lund, Sweden; Federal Centre of Heart, Blood and Endocrinology, St. Petersburg, Russia. Electronic address: marina.m.demidova@gmail.com.
authors.forename: Marina M
authors.initials: MM
authors.lastname: Demidova
authors.affiliation: Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano, Italy; Aragon Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Aragon, Spain; CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Zaragoza, Spain.
authors.forename: Alba
authors.initials: A
authors.lastname: Martín-Yebra
authors.affiliation: Department of Cardiology, Lund University, Lund, Sweden.
authors.forename: Jesper
authors.initials: J
authors.lastname: van der Pals
authors.affiliation: Department of Cardiology, Lund University, Lund, Sweden.
authors.forename: Sasha
authors.initials: S
authors.lastname: Koul
authors.affiliation: Department of Cardiology, Lund University, Lund, Sweden.
authors.forename: David
authors.initials: D
authors.lastname: Erlinge
authors.affiliation: Aragon Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Aragon, Spain; CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Zaragoza, Spain.
authors.forename: Pablo
authors.initials: P
authors.lastname: Laguna
authors.affiliation: Aragon Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Aragon, Spain; CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Zaragoza, Spain.
authors.forename: Juan Pablo
authors.initials: JP
authors.lastname: Martínez
authors.affiliation: Department of Cardiology, Lund University, Lund, Sweden; Arrhythmiaclinic, Skåne University Hospital, Lund, Sweden.
authors.forename: Pyotr G
authors.initials: PG
authors.lastname: Platonov
mesh_terms: D000818:Animals; D004562:Electrocardiography; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000503:physiopathology; D011237:Predictive Value of Tests; D012372:ROC Curve; D013552:Swine; D014693:Ventricular Fibrillation / Q000175:diagnosis* / Q000503:physiopathology
keywords: Early repolarization; J wave; Myocardial infarction; QRS duration; Ventricular fibrillation