title: Ventricular arrhythmias in super-responders to cardiac resynchronization therapy.
abstract: OBJECTIVE
  Cardiac resynchronization therapy is associated with improved quality of life and reduced morbidity and mortality in patients with severe ventricular dysfunction and wide QRS. However, its role in the reduction of ventricular arrhythmias is more controversial.
  
  
  METHODS
  We compared the incidence of ventricular arrhythmias in patients who were undergoing cardiac resynchronization therapy with an implantable cardioverter-defibrillator in terms of the degree of echocardiographic response to resynchronization. Patients were classified in 3 subgroups;super-responders, responders, and nonresponders.
  
  
  RESULTS
  We included 196 patients who were followed up for a median 30.1 months [interquartile range, 18.0-55.1 months]. We recorded the presence of ventricular arrhythmias in 37 patients (18.8%); 3 patients (5.9%) in the super-responder group had ventricular arrhythmias vs 14 (22.2%) among the responders and 20 (24.4%) in the group of nonresponders (P = .025). In multivariate analysis, the only independent predictors of the appearance of ventricular arrhythmias were secondary-prevention device implantation (odds ratio = 4.04; 95% confidence interval, 1.52-10.75; P=.005), absence of echocardiographic super-response (odds ratio=3.81; 95% confidence interval, 1.04-13.93; P=043), QRS >160 ms (odds ratio=2.39; 95% confidence interval, 1.00-1.35; P=.049) and treatment with amiodarone (odds ratio=2.47; 95% confidence interval, 1.03-5.91; P=.041).
  
  
  CONCLUSIONS
  The patients classified as super-responders to cardiac resynchronization therapy had a significant reduction in incidence of ventricular arrhythmias by comparison with the other patients. Despite this, arrhythmic episodes do not completely disappear in this subgroup.
authors.affiliation: Unidad de Arritmias, Servicio de Cardiología, Hospital Universitario Puerta de Hierro Majadahonda, Majadahonda, Madrid, Spain; Servicio de Cardiología, Hospital Universitario Quirón, Universidad Europea de Madrid, Madrid, Spain; Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain.
authors.forename: Inés
authors.initials: I
authors.lastname: García-Lunar
authors.affiliation: Unidad de Arritmias, Servicio de Cardiología, Hospital Universitario Puerta de Hierro Majadahonda, Majadahonda, Madrid, Spain. Electronic address: vcastrou14@me.com.
authors.forename: Víctor
authors.initials: V
authors.lastname: Castro-Urda
authors.affiliation: Unidad de Arritmias, Servicio de Cardiología, Hospital Universitario Puerta de Hierro Majadahonda, Majadahonda, Madrid, Spain.
authors.forename: Jorge
authors.initials: J
authors.lastname: Toquero-Ramos
authors.affiliation: Unidad de Imagen Cardiaca, Servicio de Cardiología, Hospital Universitario Puerta de Hierro Majadahonda, Majadahonda, Madrid, Spain.
authors.forename: Susana
authors.initials: S
authors.lastname: Mingo-Santos
authors.affiliation: Unidad de Imagen Cardiaca, Servicio de Cardiología, Hospital Universitario Puerta de Hierro Majadahonda, Majadahonda, Madrid, Spain.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Moñivas-Palomero
authors.affiliation: Unidad de Imagen Cardiaca, Servicio de Cardiología, Hospital Universitario Puerta de Hierro Majadahonda, Majadahonda, Madrid, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Daniela Mitroi
authors.affiliation: Unidad de Arritmias, Servicio de Cardiología, Hospital Universitario Puerta de Hierro Majadahonda, Majadahonda, Madrid, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Sánchez-García
authors.affiliation: Unidad de Arritmias, Servicio de Cardiología, Hospital Universitario Puerta de Hierro Majadahonda, Majadahonda, Madrid, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Pérez-Pereira
authors.affiliation: Unidad de Arritmias, Servicio de Cardiología, Hospital Universitario Puerta de Hierro Majadahonda, Majadahonda, Madrid, Spain.
authors.forename: Hugo E
authors.initials: HE
authors.lastname: Delgado
authors.affiliation: Unidad de Arritmias, Servicio de Cardiología, Hospital Universitario Puerta de Hierro Majadahonda, Majadahonda, Madrid, Spain.
authors.forename: Ignacio
authors.initials: I
authors.lastname: Fernández-Lozano
mesh_terms: D001145:Arrhythmias, Cardiac / Q000503:physiopathology / Q000628:therapy*; D058406:Cardiac Resynchronization Therapy; D017147:Defibrillators, Implantable; D004452:Echocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: Arritmias ventriculares; Cardiac resynchronization therapy; Super-responders; Superrespondedores; Terapia de resincronización cardiaca; Ventricular arrhythmias