title: Long-Term Outcome After CRT in the Presence of Mechanical Dyssynchrony Seen With Chronic RV Pacing or Intrinsic LBBB.
abstract: The aim of this study was to compare the volumetric response and the long-term survival after cardiac resynchronization therapy (CRT) in patients with intrinsic left bundle branch block (LBBB) versus chronic right ventricular pacing (RVP) with respect to the presence of mechanical dyssynchrony (MD).
  
  
  
  Chronic RVP induces an iatrogenic LBBB and asynchronous left ventricular contraction that is potentially reversible by upgrading to CRT.
  
  
  
  A total of 914 patients eligible for CRT (117 with conventional pacemakers and 797 with intrinsic LBBB) were included in the study. MD was visually assessed before CRT and was defined as the presence of either apical rocking and/or septal flash on baseline echocardiograms. Patients with a left ventricular end-systolic volume decrease of ≥15% during the follow-up were considered responders. Patients were followed for all-cause mortality during the median follow-up of 48 months (interquartile range: 29 to 66 months).
  
  
  
  MD was observed in 51% of patients with RVP versus 77% in patients with intrinsic LBBB (p < 0.001). Patients with RVP and MD had a similar likelihood of volumetric response as did patients with intrinsic LBBB and MD (adjusted odds ratio: 0.71; 95% confidence interval: 0.33 to 1.53; p = 0.385). There was no significant difference in long-term survival between patients with RVP and intrinsic LBBB (adjusted hazard ratio: 1.101; 95% confidence interval: 0.658 to 1.842; p = 0.714). Patients with visual MD and either intrinsic LBBB or RVP had a more favorable survival than those without MD (p < 0.001).
  
  
  
  The likelihood of volumetric response and a favorable long-term survival of patients with RVP was similar to those of patients with intrinsic LBBB and were mainly determined by the presence of MD and not by the nature of LBBB.
authors.affiliation: Department of Cardiovascular Diseases, University Hospital Gasthuisberg, Catholic University Leuven, Leuven, Belgium; Department of Cardiology, Clinical Hospital Centre Zemun, Faculty of Medicine, University of Belgrade, Belgrade, Serbia.
authors.forename: Ivan
authors.initials: I
authors.lastname: Stankovic
authors.affiliation: Department of Cardiology, Heart and Diabetes Centre of North-Rhine Westphalia, Ruhr University Bochum, Bad Oeynhausen, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Prinz
authors.affiliation: Department of Cardiovascular Diseases, University Hospital Gasthuisberg, Catholic University Leuven, Leuven, Belgium.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Ciarka
authors.affiliation: Department of Cardiovascular Diseases, University Hospital Gasthuisberg, Catholic University Leuven, Leuven, Belgium; Department of Internal Medicine and Gastroenterology, Clinical Emergency Hospital, University of Medicine and Pharmacy "Carol Davila," Bucharest, Romania.
authors.forename: Ana Maria
authors.initials: AM
authors.lastname: Daraban
authors.affiliation: Cardiovascular Center Aalst, OLV Clinic, Aalst, Belgium.
authors.forename: Yujing
authors.initials: Y
authors.lastname: Mo
authors.affiliation: Department of Cardiology, Oslo University Hospital, Rikshospitalet, Oslo, Norway.
authors.forename: Marit
authors.initials: M
authors.lastname: Aarones
authors.affiliation: Department of Cardiology, Congenital Heart Diseases and Electrotherapy, Silesian Medical University-Katowice, Silesian Center for Heart Diseases, Zabrze, Poland.
authors.forename: Mariola
authors.initials: M
authors.lastname: Szulik
authors.affiliation: Klinik für Innere Medizin und Kardiologie, St. Vinzenz Hospital, Cologne, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Winter
authors.affiliation: Department of Cardiology, Clinical Hospital Centre Zemun, Faculty of Medicine, University of Belgrade, Belgrade, Serbia.
authors.forename: Aleksandar N
authors.initials: AN
authors.lastname: Neskovic
authors.affiliation: Department of Cardiology, Congenital Heart Diseases and Electrotherapy, Silesian Medical University-Katowice, Silesian Center for Heart Diseases, Zabrze, Poland.
authors.forename: Tomasz
authors.initials: T
authors.lastname: Kukulski
authors.affiliation: Department of Cardiology, Oslo University Hospital, Rikshospitalet, Oslo, Norway; Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Svend
authors.initials: S
authors.lastname: Aakhus
authors.affiliation: Department of Cardiovascular Diseases, University Hospital Gasthuisberg, Catholic University Leuven, Leuven, Belgium.
authors.forename: Rik
authors.initials: R
authors.lastname: Willems
authors.affiliation: Klinik für Innere Medizin und Kardiologie, St. Vinzenz Hospital, Cologne, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Fehske
authors.affiliation: Cardiovascular Center Aalst, OLV Clinic, Aalst, Belgium.
authors.forename: Martin
authors.initials: M
authors.lastname: Penicka
authors.affiliation: Department of Cardiology, Clinical Hospital Centre Zemun, Faculty of Medicine, University of Belgrade, Belgrade, Serbia.
authors.forename: Lothar
authors.initials: L
authors.lastname: Faber
authors.affiliation: Department of Cardiovascular Diseases, University Hospital Gasthuisberg, Catholic University Leuven, Leuven, Belgium. Electronic address: jens-uwe.voigt@uzleuven.be.
authors.forename: Jens-Uwe
authors.initials: JU
authors.lastname: Voigt
mesh_terms: D000368:Aged; D002037:Bundle-Branch Block / Q000000981:diagnostic imaging / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D058406:Cardiac Resynchronization Therapy / Q000009:adverse effects / Q000401:mortality; D004452:Echocardiography; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009200:Myocardial Contraction; D016017:Odds Ratio; D012189:Retrospective Studies; D012307:Risk Factors; D013318:Stroke Volume; D013997:Time Factors; D016896:Treatment Outcome; D016277:Ventricular Function, Left; D016278:Ventricular Function, Right
keywords: apical rocking; cardiac resynchronization therapy; mechanical dyssynchrony; right ventricular pacing; septal flash