title: Renal sympathetic denervation inhibits the development of left ventricular mechanical dyssynchrony during the progression of heart failure in dogs.
abstract: BACKGROUND
  The purpose of this study was to investigate whether transcatheter renal sympathetic denervation (RSD) interfere with the development of left ventricular (LV) mechanical dyssynchrony during the progression of heart failure (HF).
  
  
  METHODS
  Nineteen beagles were randomly divided into sham-operated group (six dogs), control group (seven dogs), and RSD group (six dogs). Sham-operated group were implanted with pacemakers without pacing; Control group were implanted with pacemakers and underwent 3 weeks of rapid right ventricular pacing; and RSD group underwent catheter-based RSD bilaterally and were simultaneously implanted with pacemakers. Both LV strain and LV dyssynchrony were analyzed via 2D speckle-tracking strain echocardiography to evaluate LV function. Longitudinal dyssynchrony was determined as the standard deviation for time-to-peak speckle-tracking strain on apical 4- and 2-chamber views. Radial and circumferential dyssynchrony was determined as the standard deviation for time-to-peak speckle-tracking strain in mid- and base-LV short-axis views. Each myocardial function was also evaluated by averaging the peak systolic strains. LV systolic pressure (LVSP) and LV end-diastolic pressure (LVEDP) were measured. The LV interstitial fibrosis was determined by histological analysis. Plasma angiotensin II (Ang II), aldosterone and norepinephrine (NE) levels were also measured.
  
  
  RESULTS
  After 3 weeks, all of the dogs in both the control and RSD groups showed greater LV end-diastolic volume compared with the sham-operated group; however, the dogs in the RSD group had a higher LV ejection fraction (LVEF) than the dogs in the control group (p<0.001). The LV systolic strains were higher in the RSD group than in the control group (p<0.001 for longitudinal, circumferential and radial strain, respectively). The levels of LV dyssynchrony were lower in the RSD group than in the control group (p<0.001 for longitudinal, circumferential and radial dyssynchrony, respectively). Compared with dogs with control alone, RSD dogs had lower LV end-diastolic pressures and less fibrous tissue. The levels of plasma Ang II, aldosterone and NE were lower in the RSD group than in the control group.
  
  
  CONCLUSIONS
  RSD inhibites the development of left ventricular mechanical dyssynchrony during the progression of heart failure in dogs.
authors.forename: Wei
authors.initials: W
authors.lastname: Hu
authors.forename: Qing-yan
authors.initials: QY
authors.lastname: Zhao
authors.forename: Sheng-bo
authors.initials: SB
authors.lastname: Yu
authors.forename: Bin
authors.initials: B
authors.lastname: Sun
authors.forename: Liao
authors.initials: L
authors.lastname: Chen
authors.forename: Sheng
authors.initials: S
authors.lastname: Cao
authors.affiliation: Department of Ultrasound, Renmin Hospital of Wuhan University, Jiefang Road 238#, Wuchang District, Wuhan 430060, China. gzrdoct@163.com.
authors.forename: Rui-qiang
authors.initials: RQ
authors.lastname: Guo
mesh_terms: D000818:Animals; D018450:Disease Progression; D004285:Dogs; D004452:Echocardiography; D054459:Elasticity Imaging Techniques; D006333:Heart Failure / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D007668:Kidney / Q000294:innervation* / Q000601:surgery*; D013318:Stroke Volume; D013562:Sympathectomy / Q000379:methods*; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging / Q000209:etiology* / Q000517:prevention & control*