title: Noninvasive electrocardiographic mapping to improve patient selection for cardiac resynchronization therapy: beyond QRS duration and left bundle branch block morphology.
abstract: OBJECTIVE
  This study sought to investigate whether noninvasive electrocardiographic activation mapping is a useful method for predicting response to cardiac resynchronization therapy (CRT).
  
  
  BACKGROUND
  One third of the patients appear not to respond to CRT when they are selected according to QRS duration.
  
  
  METHODS
  We performed electrocardiographic activation mapping in 33 consecutive CRT candidates (QRS duration ≥120 ms). In 18 patients, the 12-lead electrocardiographic morphology was left bundle branch block (LBBB), and in 15, it was nonspecific intraventricular conduction disturbance (NICD). Three indexes of electrical dyssynchrony were derived from intrinsic maps: right and left ventricular total activation times and ventricular electrical uncoupling (VEU) (difference between the left ventricular [LV] and right ventricular mean activation times). We assessed the ability of these parameters to predict response, measured using a clinical composite score, after 6 months of CRT.
  
  
  RESULTS
  Electrocardiographic maps revealed homogeneous patterns of activation and consistently greater VEU and LV total activation time (LVTAT) in patients with LBBB compared with heterogeneous activation sequences and shorter VEU and LVTAT in NICD patients (VEU: 75 ± 12 ms vs. 40 ± 22 ms; p < 0.001; LVTAT: 115 ± 21 ms vs. 91 ± 34 ms; p = 0.03). LBBB and NICD patients had similar right ventricular total activation times (62 ± 30 ms vs. 58 ± 26 ms; p = 0.7). The area under the receiver-operating characteristic curve indicated that VEU (area under the curve [AUC]: 0.88) was significantly superior to QRS duration (AUC: 0.73) and LVTAT (AUC: 0.72) for predicting CRT response (p < 0.05). With a 50-ms cutoff value, VEU identified CRT responders with 90% sensitivity and 82% specificity whether LBBB was present or not.
  
  
  CONCLUSIONS
  Ventricular electrical uncoupling measured by electrocardiographic mapping predicted clinical CRT response better than QRS duration or the presence of LBBB.
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, CHU Bordeaux, LIRYC, L'Institut de rythmologie et modélisation cardiaque, Université de Bordeaux, Bordeaux, France. Electronic address: sylvain.ploux@free.fr.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Ploux
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, CHU Bordeaux, LIRYC, L'Institut de rythmologie et modélisation cardiaque, Université de Bordeaux, Bordeaux, France; Maastricht University, Cardiovascular Research Institute Maastricht (CARIM), Maastricht, the Netherlands.
authors.forename: Joost
authors.initials: J
authors.lastname: Lumens
authors.affiliation: Imperial College London, London, United Kingdom.
authors.forename: Zachary
authors.initials: Z
authors.lastname: Whinnett
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, CHU Bordeaux, LIRYC, L'Institut de rythmologie et modélisation cardiaque, Université de Bordeaux, Bordeaux, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Montaudon
authors.affiliation: CardioInsight Technologies Inc., Cleveland, Ohio.
authors.forename: Maria
authors.initials: M
authors.lastname: Strom
authors.affiliation: CardioInsight Technologies Inc., Cleveland, Ohio.
authors.forename: Charu
authors.initials: C
authors.lastname: Ramanathan
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, CHU Bordeaux, LIRYC, L'Institut de rythmologie et modélisation cardiaque, Université de Bordeaux, Bordeaux, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Derval
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, CHU Bordeaux, LIRYC, L'Institut de rythmologie et modélisation cardiaque, Université de Bordeaux, Bordeaux, France.
authors.forename: Adlane
authors.initials: A
authors.lastname: Zemmoura
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, CHU Bordeaux, LIRYC, L'Institut de rythmologie et modélisation cardiaque, Université de Bordeaux, Bordeaux, France.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Denis
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, CHU Bordeaux, LIRYC, L'Institut de rythmologie et modélisation cardiaque, Université de Bordeaux, Bordeaux, France.
authors.forename: Maxime
authors.initials: M
authors.lastname: De Guillebon
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, CHU Bordeaux, LIRYC, L'Institut de rythmologie et modélisation cardiaque, Université de Bordeaux, Bordeaux, France.
authors.forename: Ashok
authors.initials: A
authors.lastname: Shah
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, CHU Bordeaux, LIRYC, L'Institut de rythmologie et modélisation cardiaque, Université de Bordeaux, Bordeaux, France.
authors.forename: Mélèze
authors.initials: M
authors.lastname: Hocini
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, CHU Bordeaux, LIRYC, L'Institut de rythmologie et modélisation cardiaque, Université de Bordeaux, Bordeaux, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Jaïs
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, CHU Bordeaux, LIRYC, L'Institut de rythmologie et modélisation cardiaque, Université de Bordeaux, Bordeaux, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Ritter
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, CHU Bordeaux, LIRYC, L'Institut de rythmologie et modélisation cardiaque, Université de Bordeaux, Bordeaux, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Haïssaguerre
authors.affiliation: Heart and Vascular Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Wilkoff
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, CHU Bordeaux, LIRYC, L'Institut de rythmologie et modélisation cardiaque, Université de Bordeaux, Bordeaux, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Bordachar
mesh_terms: D000368:Aged; D002037:Bundle-Branch Block / Q000503:physiopathology*; D058406:Cardiac Resynchronization Therapy / Q000379:methods*; D015331:Cohort Studies; D017147:Defibrillators, Implantable; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006333:Heart Failure / Q000503:physiopathology* / Q000628:therapy*; D006352:Heart Ventricles / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008955:Models, Cardiovascular; D018579:Patient Selection; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016277:Ventricular Function, Left / Q000502:physiology