title: Acute Effects of Multisite Biventricular Pacing on Dyssynchrony and Hemodynamics in Canines With Heart Failure.
abstract: BACKGROUND
  Multisite biventricular pacing (MSP) has been proposed as an alternative strategy to improve the efficiency of conventional biventricular pacing (BVP), but its utility remains unclear. This study sought to investigate whether MSP induced better synchrony and hemodynamic effects in canines with heart failure.
  
  
  RESULTS
  After 3 weeks' rapid right ventricular pacing, 7 canines were sutured with 4 left ventricular (LV) leads on the anterior, lateral, posterior, and apical walls and followed by MSP and BVP. Hemodynamic, electrocardiographic, and echocardiographic parameters were measured. Dyssynchrony was assessed by tissue Doppler imaging for Yu-index (longitudinal direction) and speckle tracking imaging for the standard deviation of time to peak radial strains (SDε, radial direction). Compared with BVP, mean MSP reduced QRS width (P < .05), Yu-index (25.3 ± 1.9 ms vs 31.6 ± 4.3 ms, P = .008), SDε(32.8 ± 5.9 ms vs 37.3 ± 7.9 ms, P = .032), and LV end-diastolic pressure (P < .05). The optimal pacing site combination improved QRS width, Yu-index, SDε, LV end-diastolic pressure, and the maximum derivative of LV pressure (dP/dtmax) significantly (all P < .05), but the worst MSP (with the smallest dP/dtmax) did not show any improvement to BVP.
  
  
  CONCLUSIONS
  MSP is superior to BVP in reducing dyssynchrony and improving hemodynamics. The pacing site combination has a potential effect on MSP response.
authors.affiliation: Department of Cardiology, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510120, China; Key Laboratory of Cardiac Electrophysiology and Arrhythmia in Guangdong Province, 107 Yanjiang West Road, Guangzhou 510120, China.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Qiu
authors.affiliation: Department of Cardiology, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510120, China.
authors.forename: Li
authors.initials: L
authors.lastname: Yang
authors.affiliation: Department of Cardiology, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510120, China; Key Laboratory of Cardiac Electrophysiology and Arrhythmia in Guangdong Province, 107 Yanjiang West Road, Guangzhou 510120, China.
authors.forename: Jing-Ting
authors.initials: JT
authors.lastname: Mai
authors.affiliation: Department of Cardiology, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510120, China; Key Laboratory of Cardiac Electrophysiology and Arrhythmia in Guangdong Province, 107 Yanjiang West Road, Guangzhou 510120, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Cardiology, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510120, China; Key Laboratory of Cardiac Electrophysiology and Arrhythmia in Guangdong Province, 107 Yanjiang West Road, Guangzhou 510120, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Xie
authors.affiliation: Department of Cardiology, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510120, China; Key Laboratory of Cardiac Electrophysiology and Arrhythmia in Guangdong Province, 107 Yanjiang West Road, Guangzhou 510120, China. Electronic address: tjcyx1995@163.com.
authors.forename: Yang-Xin
authors.initials: YX
authors.lastname: Chen
authors.affiliation: Department of Cardiology, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510120, China; Key Laboratory of Cardiac Electrophysiology and Arrhythmia in Guangdong Province, 107 Yanjiang West Road, Guangzhou 510120, China. Electronic address: dr_wjf@hotmail.com.
authors.forename: Jing-Feng
authors.initials: JF
authors.lastname: Wang
mesh_terms: D000818:Animals; D058406:Cardiac Resynchronization Therapy / Q000379:methods*; D004195:Disease Models, Animal; D004285:Dogs; D004452:Echocardiography; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods*; D006333:Heart Failure / Q000503:physiopathology / Q000628:therapy; D006339:Heart Rate; D006352:Heart Ventricles / Q000503:physiopathology; D006439:Hemodynamics / Q000502:physiology*; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology
keywords: Cardiac resynchronization therapy; hemodynamic; mechanical dyssynchrony; multisite biventricular pacing