title: LV mechanical dispersion as a predictor of ventricular arrhythmia in patients with advanced systolic heart failure : A pilot study.
abstract: BACKGROUND
  Myocardial mechanical dyssynchrony induced by the presence of postinfarction scar and/or conduction abnormalities in patients with a left ventricular ejection fraction (LVEF) of < 35 % may be associated with a greater propensity toward inducing serious ventricular arrhythmia [(ventricular tachycardia (VT), ventricular fibrillation (VF)] and sudden cardiac death. The assessment of regional myocardial function using tissue Doppler echocardiography (TDE) allows for noninvasive analysis of regional mechanical dysfunction (LV mechanical dispersion).
  
  
  OBJECTIVE
  The aim of this study was to evaluate the TDE-based mechanical dispersion as a potential echocardiographic predictor of VT/VF.
  
  
  METHODS
  The study group consisted of 47 consecutive ambulatory patients with implanted cardiac resynchronization therapy-defibrillator (CRT-D) devices who were divided into two groups: Group 1 (n = 29) comprised patients with recorded episodes of VT/VF, in whom baseline TDE data were available, and group 2 (n = 18) comprised patients without registered VT/VF in the device memory within 4 years after implantation. LV mechanical dispersion was defined as the standard deviation of the time measured from the beginning of the QRS complex to the peak longitudinal strain in apical four-chamber and two-chamber views. A retrospective quantitative assessment of LV regional deformation was based on the color tissue velocity recordings.
  
  
  RESULTS
  The average time to event after implantation was 345 days. Patients with electrical events demonstrated greater mechanical dispersion: 99.14 ± 33.60 vs. 72.98 ± 19.70, p=0.002.
  
  
  CONCLUSIONS
  During the 4-year follow-up, patients with documented VT/VF were characterized by significantly higher LV mechanical dispersion as compared with patients without electrical events. Measurement of LV mechanical dispersion might be helpful in determining the risk of sudden cardiac death.
authors.affiliation: Medical University of Silesia in Katowice, School of Medicine with the Division of Dentistry in Zabrze, Zabrze, Poland. macgrzegorz@gmail.com.
authors.forename: G
authors.initials: G
authors.lastname: Banasik
authors.affiliation: Medical University of Silesia in Katowice, School of Medicine with the Division of Dentistry in Zabrze, Zabrze, Poland.
authors.forename: O
authors.initials: O
authors.lastname: Segiet
authors.affiliation: Medical University of Silesia in Katowice, School of Medicine with the Division of Dentistry in Zabrze, Zabrze, Poland.
authors.forename: M
authors.initials: M
authors.lastname: Elwart
authors.affiliation: Department of Cardiology, Congenital Heart Disease and Electrotherapy, Silesian Center for Heart Diseases, Zabrze, Poland.
authors.forename: M
authors.initials: M
authors.lastname: Szulik
authors.affiliation: Department of Cardiology, Congenital Heart Disease and Electrotherapy, Silesian Center for Heart Diseases, Zabrze, Poland.
authors.forename: R
authors.initials: R
authors.lastname: Lenarczyk
authors.affiliation: Department of Cardiology, Congenital Heart Disease and Electrotherapy, Silesian Center for Heart Diseases, Zabrze, Poland.|Medical University of Silesia in Katowice, Katowice, Poland.
authors.forename: Z
authors.initials: Z
authors.lastname: Kalarus
authors.affiliation: Department of Cardiology, Congenital Heart Disease and Electrotherapy, Silesian Center for Heart Diseases, Zabrze, Poland.|Medical University of Silesia in Katowice, Katowice, Poland.
authors.forename: T
authors.initials: T
authors.lastname: Kukulski
mesh_terms: D000368:Aged; D015984:Causality; D015897:Comorbidity; D016757:Death, Sudden, Cardiac / Q000453:epidemiology*; D004452:Echocardiography / Q000706:statistics & numerical data; D004562:Electrocardiography / Q000379:methods / Q000706:statistics & numerical data; D005260:Female; D006333:Heart Failure / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D008297:Male; D010865:Pilot Projects; D011044:Poland / Q000453:epidemiology; D015995:Prevalence; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D012680:Sensitivity and Specificity; D015996:Survival Rate; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000401:mortality*; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000401:mortality*; D014693:Ventricular Fibrillation / Q000175:diagnosis / Q000401:mortality*
keywords: Dilated cardiomyopathy; Implantable cardioverter–defibrillator; Mechanical dyssynchrony; Sudden cardiac death; Ultrasound strain