title: QRS complex widening as a predictor of appropriate implantable cardioverter-defibrillator (ICD) therapy and higher mortality risk in primary prevention ICD patients.
abstract: OBJECTIVE
  Effectiveness of implantable cardioverter-defibrillators (ICD) in patients with reduced left ventricular ejection fraction after myocardial infarction has been documented in large randomised trials. We analysed the predictive value of clinical factors at the time of implantation for adequate ICD interventions and mortality risk.
  
  
  METHODS
  We analysed 121 consecutive patients (15 women, 106 [88%] men; mean age 62 ± 10 years) with coronary artery disease in whom ICD was implanted for primary prevention between 2001 and 2007. Mean duration of follow-up was 876 ± 538 days.
  
  
  RESULTS
  Forty-four (36.4%) patients had adequate ICD interventions. In the Cox analysis, wider QRS complexes (hazard ration [HR] per each 10 ms increment: 1.13, confidence interval [CI] 1.039-1.229, p = 0.0045) and younger age at the time of ICD implantation (HR per each 10 year increment: 0.7, CI 0.5-0.9, p = 0.0081) were associated with a higher probability of adequate intervention. Wider QRS complexes were associated with a higher probability of electrical storm (HR 1.059, CI 1.014-1.045, p = 0.0002). During follow-up, 21 (17.4%) patients died. In the Cox analysis, wider QRS complexes (HR per each 10 ms increment: 1.123, CI 1.011-1.248, p = 0.0306 [in univariate analysis only]), older age at the time of implantation (HR per each 10 year increment: 1.7, CI 1.1-2.8, p = 0.0396) and higher NYHA class (HR 4.4, CI 1.7-11.5, p = 0.0022) were associated with increased mortality. Mortality was reduced by previous revascularisation (HR 0.3, CI 0.1-0.7, p = 0.006).
  
  
  CONCLUSIONS
  Patients with wider QRS complexes at the time of ICD implantation had a higher probability of adequate device intervention and mortality risk. QRS complex widening was also associated with a higher incidence of electrical storm.
authors.affiliation: 2nd Coronary Artery Disease, Institute of Cardiology, Warsaw, Poland. maciag_o@poczta.onet.pl
authors.forename: Aleksander
authors.initials: A
authors.lastname: Maciąg
authors.forename: Andrzej
authors.initials: A
authors.lastname: Przybylski
authors.forename: Maciej
authors.initials: M
authors.lastname: Sterliński
authors.forename: Michał
authors.initials: M
authors.lastname: Lewandowski
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Gepner
authors.forename: Ilona
authors.initials: I
authors.lastname: Kowalik
authors.forename: Paweł
authors.initials: P
authors.lastname: Derejko
authors.forename: Mariusz
authors.initials: M
authors.lastname: Pytkowski
authors.forename: Lukasz
authors.initials: L
authors.lastname: Szumowski
authors.forename: Hanna
authors.initials: H
authors.lastname: Szwed
mesh_terms: D000368:Aged; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000401:mortality / Q000628:therapy*; D011237:Predictive Value of Tests; D011322:Primary Prevention; D016016:Proportional Hazards Models; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000401:mortality / Q000628:therapy*