title: Non-invasive electromechanical activation imaging as a tool to study left ventricular dyssynchronous patients: Implication for CRT therapy.
abstract: Electromechanical de-coupling is hypothesized to explain non-response of dyssynchrony patient to cardiac resynchronization therapy (CRT). In this pilot study, we investigated regional electromechanical uncoupling in 10 patients referred for CRT using two non-invasive electrical and mechanical imaging techniques (CMR tissue tracking and ECGI).
  
  
  
  Reconstructed regional electrical and mechanical activation captured delayed LBBB propagation direction from septal to anterior/inferior and finally to lateral walls as well as from LV apical to basal. All 5 responders demonstrated significantly delayed mechanical and electrical activation on the lateral LV wall at baseline compared to the non-responders (P<.05). On follow-up ECGI, baseline electrical activation patterns were preserved in native rhythm and global LV activation time was reduced with biventricular pacing.
  
  
  
  The combination of novel imaging techniques of ECGI and CMR tissue tracking can be used to assess spatial concordance of LV electrical and mechanical activation to gain insight into electromechanical coupling.
authors.affiliation: Division of Cardiology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA. Electronic address: fady.dawoud@gmail.com.
authors.forename: Fady
authors.initials: F
authors.lastname: Dawoud
authors.affiliation: Division of Cardiology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: David D
authors.initials: DD
authors.lastname: Spragg
authors.affiliation: Division of Cardiology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Ronald D
authors.initials: RD
authors.lastname: Berger
authors.affiliation: Division of Cardiology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Alan
authors.initials: A
authors.lastname: Cheng
authors.affiliation: Department of Electrical and Computer Engineering, Dalhousie University, Halifax, NS, Canada.
authors.forename: B Milan
authors.initials: BM
authors.lastname: Horáček
authors.affiliation: Division of Cardiology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Henry R
authors.initials: HR
authors.lastname: Halperin
authors.affiliation: Division of Cardiology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA; Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Albert C
authors.initials: AC
authors.lastname: Lardo
mesh_terms: D000465:Algorithms; D057791:Cardiac Imaging Techniques / Q000379:methods*; D058406:Cardiac Resynchronization Therapy / Q000379:methods; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012984:Software; D013318:Stroke Volume; D013382:Subtraction Technique; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000517:prevention & control* / Q000628:therapy
keywords: CRT; ECGI; dyssynchrony; electromechanical uncoupling