title: Prognostic importance of postoperative QRS widening in patients with heart failure receiving cardiac resynchronization therapy.
abstract: Landmark reports have suggested that patients with QRS widening immediately after cardiac resynchronization therapy (CRT) experienced less frequently reverse left ventricular remodeling during follow-up.
  
  
  
  We sought to investigate the relationship between postoperative QRS widening relative to baseline and mortality in a prospective cohort of heart failure patients receiving CRT.
  
  
  
  A 12-lead electrocardiogram was recorded for 237 heart failure patients (New York Heart Association class II to IV, left ventricular ejection fraction ≤35%, and QRS width ≥120 ms) before and immediately after CRT device implantation. The relationships between QRS widening, all-cause and cardiovascular mortality, and echocardiographic response to CRT were studied.
  
  
  
  During a median follow-up of 24 months, 39 patients died. Fifty patients (21%) experienced QRS widening after CRT [QRS(+) group]. During follow-up, all-cause mortality was higher in QRS(+) patients than in QRS(-) patients (36-month survival free from death 81% ± 7% vs 64% ± 16%; log rank, P = .029). After adjustment for important prognostic confounders, QRS(+) patients remained associated with an excess overall mortality (adjusted hazard ratio [HR] 2.67; 95% confidence interval 1.07-6.65; P = .035) and cardiovascular mortality (adjusted hazard ratio 3.63; 95% confidence interval 1.13-11.65; P = .03). QRS(+) patients were less frequent responders to CRT than were QRS(-) patients (20 [47%] vs 136 [83%]; P < .0001).
  
  
  
  Postoperative QRS widening relative to baseline after CRT is associated with a considerable increased mortality risk during follow-up. Whether QRS narrowing should be achieved to optimize CRT placement, and thereby increase the rate of CRT responders and improve outcome, deserves further research.
authors.affiliation: GCS-Groupement des hôpitaux de l'institut Catholique de Lille/Faculté Libre de Médecine, Département de Cardiologie, Université Catholique de Lille, Lille, France; INSERM U 1088, Université de Picardie, Amiens, France.
authors.forename: Aymeric
authors.initials: A
authors.lastname: Menet
authors.affiliation: GCS-Groupement des hôpitaux de l'institut Catholique de Lille/Faculté Libre de Médecine, Département de Cardiologie, Université Catholique de Lille, Lille, France; Centre Hospitalier de la région de Saint Omer, Saint Omer, France.
authors.forename: Hélène
authors.initials: H
authors.lastname: Bardet-Bouchery
authors.affiliation: GCS-Groupement des hôpitaux de l'institut Catholique de Lille/Faculté Libre de Médecine, Département de Cardiologie, Université Catholique de Lille, Lille, France.
authors.forename: Yves
authors.initials: Y
authors.lastname: Guyomar
authors.affiliation: GCS-Groupement des hôpitaux de l'institut Catholique de Lille/Faculté Libre de Médecine, Département de Cardiologie, Université Catholique de Lille, Lille, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Graux
authors.affiliation: GCS-Groupement des hôpitaux de l'institut Catholique de Lille/Faculté Libre de Médecine, Département de Cardiologie, Université Catholique de Lille, Lille, France.
authors.forename: François
authors.initials: F
authors.lastname: Delelis
authors.affiliation: GCS-Groupement des hôpitaux de l'institut Catholique de Lille/Faculté Libre de Médecine, Département de Cardiologie, Université Catholique de Lille, Lille, France.
authors.forename: Anne-Laure
authors.initials: AL
authors.lastname: Castel
authors.affiliation: GCS-Groupement des hôpitaux de l'institut Catholique de Lille/Faculté Libre de Médecine, Département de Cardiologie, Université Catholique de Lille, Lille, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Heuls
authors.affiliation: GCS-Groupement des hôpitaux de l'institut Catholique de Lille/Faculté Libre de Médecine, Département de Cardiologie, Université Catholique de Lille, Lille, France.
authors.forename: Estelle
authors.initials: E
authors.lastname: Cuvelier
authors.affiliation: GCS-Groupement des hôpitaux de l'institut Catholique de Lille/Faculté Libre de Médecine, Département de Cardiologie, Université Catholique de Lille, Lille, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Gevaert
authors.affiliation: Département de Cardiologie, CHU de Grenoble, Grenoble, France.
authors.forename: Pierre-Vladimir
authors.initials: PV
authors.lastname: Ennezat
authors.affiliation: INSERM U 1088, Université de Picardie, Amiens, France; Pôle Cardiovasculaire et Thoracique, Centre Hospitalier Universitaire Amiens, Amiens, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Tribouilloy
authors.affiliation: GCS-Groupement des hôpitaux de l'institut Catholique de Lille/Faculté Libre de Médecine, Département de Cardiologie, Université Catholique de Lille, Lille, France; INSERM U 1088, Université de Picardie, Amiens, France. Electronic address: sylvestre.marechaux@yahoo.fr.
authors.forename: Sylvestre
authors.initials: S
authors.lastname: Maréchaux
mesh_terms: D000368:Aged; D058406:Cardiac Resynchronization Therapy / Q000379:methods*; D006348:Cardiac Surgical Procedures; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006333:Heart Failure / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D008297:Male; D011184:Postoperative Period; D011379:Prognosis; D011446:Prospective Studies; D013318:Stroke Volume; D016277:Ventricular Function, Left / Q000502:physiology; D020257:Ventricular Remodeling
keywords: Cardiac resynchronization therapy; Electrocardiogram; Heart failure; Outcome; QRS duration