title: Evaluation of left ventricular longitudinal function and synchrony after dual chamber pacemaker implantation.
abstract: OBJECTIVE
  To evaluate left ventricular (LV) longitudinal function and dyssynchrony mechanisms after dual chamber pacemaker implantation.
  
  
  METHODS
  The speckle tracking imaging technique was used for quantification of global longitudinal function of the left ventricle and for dyssynchrony evaluation before pacemaker implantation and after 3-month follow-up. The study group consisted of 98 patients with conventional indications for dual chamber pacemaker implantation.
  
  
  RESULTS
  Speckle tracking echocardiographic methods and image postprocessing revealed impairment of global longitudinal strain and significant LV dyssynchrony derived from 12 basal and mid-septum segments usually untraceable with conventional echocardiographic methods. Despite good physical performance and ejection fraction, global longitudinal strain significantly decreased in all patients from -15.08±0.46 to -13.56±0.5 (P<0.05) as well as mitral annulus movement decreased from 11.57±2.41 to 8.46±1.74cm/s (P<0.001) and from 12.55±2.75 to 10.78±2.82mm (P<0.001). It was expected that patients with dual chamber pacemaker will develop inter- and intraventricular dyssynchrony, but our study showed that pacing lead position did not prevent from LV dysynchronisation and only changed the mechanism.
  
  
  CONCLUSIONS
  Global longitudinal strain and LV dyssynchrony assessment enables us to detect early signs of LV dysfunction. Mechanisms of dyssynchrony development will be useful for pacemaker programing choices in order to prevent further dyssynchronisation.
authors.affiliation: Department of Cardiology, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania. Electronic address: kristinabar@gmail.com.
authors.forename: Kristina
authors.initials: K
authors.lastname: Baronaitė-Dūdonienė
authors.affiliation: Institute of Cardiology, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania.
authors.forename: Jolanta
authors.initials: J
authors.lastname: Vaškelytė
authors.affiliation: Department of Cardiology, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania.
authors.forename: Aras
authors.initials: A
authors.lastname: Puodžiukynas
authors.affiliation: Department of Cardiology, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania.
authors.forename: Vytautas
authors.initials: V
authors.lastname: Zabiela
authors.affiliation: Department of Cardiology, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania.
authors.forename: Tomas
authors.initials: T
authors.lastname: Kazakevičius
authors.affiliation: Department of Cardiology, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania.
authors.forename: Gintarė
authors.initials: G
authors.lastname: Šakalytė
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D054537:Atrioventricular Block / Q000601:surgery*; D058409:Cardiac Resynchronization Therapy Devices; D004452:Echocardiography; D005260:Female; D006801:Humans; D008297:Male; D019919:Prosthesis Implantation; D012804:Sick Sinus Syndrome / Q000601:surgery*; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology*; D020257:Ventricular Remodeling / Q000502:physiology*
keywords: Biomedical electronics; Dual chamber pacemaker; Dyssynchrony; Myocardial deformation imaging