title: Sudden cardiac death in adults with congenital heart disease: does QRS-complex fragmentation discriminate in structurally abnormal hearts?
abstract: Sudden cardiac death (SCD) causes a large portion of all mortality in adult congenital heart disease (ACHD) patients. However, identification of high-risk patients remains challenging. Fragmented QRS-complexes (fQRS) are a marker for SCD in patients with acquired heart disease but data in ACHD patients are lacking. We therefore aim to evaluate the prognostic value of fQRS for SCD in ACHD patients.
  
  
  
  From a multicentre cohort of 25 790 ACHD patients, we included tachyarrhythmic SCD cases (n = 147), and controls (n = 266) matched by age, gender, congenital defect and (surgical) intervention. fQRS was defined as ≥1 discontinuous deflection in narrow QRS-complexes, and ≥2 in wide QRS-complexes (>120 ms), in two contiguous ECG leads. We calculated odds ratios (OR) using univariable and multivariable conditional logistic regression models correcting for impaired systemic ventricular function, heart failure and QRS duration >120 ms. ECGs of 147 SCD cases (65% male, median age of death 34 years) and of 266 controls were assessed. fQRS was present in 51% of cases and 34% of controls (OR 2.0, P = 0.003). In multivariable analysis, fQRS was independently associated with SCD (OR 1.9, P = 0.01). The most common diagnose of SCD cases was tetralogy of Fallot (ToF, 34 cases). In ToF, fQRS was present in 71% of cases vs. 43% of controls (OR for SCD 2.8, P = 0.03).
  
  
  
  fQRS was independently associated with SCD in ACHD patients in a cohort of SCD patients and matched controls. fQRS may therefore contribute to the decision when evaluating ACHD patients for primary prevention of SCD.
authors.affiliation: Department of Cardiology, Heart Center, Academic Medical Center-University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
authors.forename: Jim T
authors.initials: JT
authors.lastname: Vehmeijer
authors.affiliation: Department of Cardiology, Heart Center, Academic Medical Center-University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
authors.forename: Zeliha
authors.initials: Z
authors.lastname: Koyak
authors.affiliation: Department of Cardiology, Heart Center, Academic Medical Center-University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
authors.forename: Jouke P
authors.initials: JP
authors.lastname: Bokma
authors.affiliation: Department of Cardiology, UZ Leuven, and Department of Cardiovascular Sciences, KU Leuven, Herestraat 49, B-3000 Leuven, Belgium.
authors.forename: Werner
authors.initials: W
authors.lastname: Budts
authors.affiliation: Department of Cardiology, Toronto General Hospital, Toronto Congenital Cardiac Centre for Adults, 200 Elizabeth Street, M5G 2C4, Toronto, Ontario, Canada.
authors.forename: Louise
authors.initials: L
authors.lastname: Harris
authors.affiliation: Department of Cardiology, Heart Center, Academic Medical Center-University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.|Netherlands Heart Institute, Moreelsepark 1, 3511 EP Utrecht, The Netherlands.
authors.forename: Barbara J M
authors.initials: BJM
authors.lastname: Mulder
authors.affiliation: Department of Cardiology, Heart Center, Academic Medical Center-University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
authors.forename: Joris R
authors.initials: JR
authors.lastname: de Groot
mesh_terms: D000200:Action Potentials; D000328:Adult; D000367:Age Factors; D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000209:etiology / Q000401:mortality* / Q000503:physiopathology; D001530:Belgium / Q000453:epidemiology; D016757:Death, Sudden, Cardiac / Q000453:epidemiology*; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006330:Heart Defects, Congenital / Q000150:complications / Q000175:diagnosis / Q000401:mortality* / Q000503:physiopathology; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D009864:Ontario / Q000453:epidemiology; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors