Left ventricular mechanics in repaired tetralogy of Fallot with and without pulmonary valve replacement: analysis by three-dimensional speckle tracking echocardiography

PLoS One. 2013 Nov 6;8(11):e78826. doi: 10.1371/journal.pone.0078826. eCollection 2013.

Abstract

Background: Altered septal curvature and left ventricular (LV) geometry secondary to right ventricular (RV) dilation render two-dimensional assessment of LV mechanics difficult in repaired tetralogy of Fallot (TOF) patients. The novel three-dimensional (3D) speckle tracking echocardiography enables comprehensive evaluation of true 3D LV mechanics.

Methods and results: Seventy-six patients aged 23.6 ± 8.3 years, 55 with isolated repair (group I) and 21 with subsequent pulmonary valve replacement (group II), and 34 healthy controls were studied. Three-dimensional volume datasets were acquired for assessment of LV global and regional 3D strain, systolic dyssynchrony index (SDI), twist, twist gradient (twist/LV length), and ejection fraction. A global performance index was calculated as (global 3D strain•twist gradient)/SDI. The septal curvature and LV eccentricity were determined from the mid-ventricular short-axis. Compared with controls, group I and II patients had significantly reduced LV global 3D strain, LV twist, twist gradient, septal curvature, and global performance index, and greater LV systolic and diastolic eccentricity and SDI (all p<0.05). All but the four apical LV segments in patients had reduced regional 3D strain compared with controls (all p<0.05). Septal curvature correlated with LV global 3D strain (r=0.41, p<0.001), average septal strain (r=0.38, p<0.001), twist (r=0.32, p<0.001), twist gradient (r=0.33, p<0.001), and global performance index (r=0.43, p<0.001).

Conclusions: Adverse 3D LV mechanics as characterized by impaired global and regional 3D systolic strain, mechanical dyssynchrony, and reduced twist is related to reduced septal curvature in repaired TOF patients with and without pulmonary valve replacement.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Analysis of Variance
  • Echocardiography, Doppler, Color / methods
  • Echocardiography, Three-Dimensional / methods*
  • Female
  • Heart Ventricles / diagnostic imaging
  • Heart Ventricles / physiopathology
  • Humans
  • Male
  • Pulmonary Valve / physiopathology*
  • Pulmonary Valve / surgery
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Tetralogy of Fallot / physiopathology*
  • Tetralogy of Fallot / surgery
  • Ventricular Dysfunction, Left / diagnosis
  • Ventricular Dysfunction, Left / physiopathology*
  • Young Adult

Grant support

The study was funded by Research Grants Council General Research Fund of the Hong Kong Special Administrative Region, China (Project no. HKU 763710M). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.