Left ventricular rotational abnormalities in adult patients with corrected tetralogy of Fallot following different surgical procedures – a three-dimensional speckle-tracking echocardiographic study
Authors: Nemes A , Racz G , Kormanyos A , Domsik P , Kalapos A , Gyenes N , Ambrus N , Hartyanszky I , Bogats G , Havasi K 
Published: November 2020

Abstract

Introduction
Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease. Abnormal aortic dimensions and elasticity parameters have been long described for corrected TOF (cTOF) together with left ventricular (LV) rotational abnormalities. The present study focuses on investigating LV rotational mechanics in cTOF, and possible correlation of these parameters with aortic elastic properties. It was also aimed to be examined whether different surgical strategies has any effect on the results.

Methods
The study involved 26 adult cTOF patients, from which 14 had palliative surgery first [Blaloc-Taussig (n=10), Waterstone-Cooley (n=2) shunts, or Brock procedure (n=2)] (mean age at the repair: 7.3±10.2 years) and a late total correction (mean age at the repair: 10.0±13.3 years) (pcTOF), while the early total correction was the treatment of choice in 12 patients (mean age at the repair: 4.2±3.2 years) (etrTOF). Their results were compared to that of 37 age- and gender-matched healthy adults. Routine transthoracic two-dimensional Doppler echocardiography extended with assessment of aortic elastic properties and three-dimensional speckle-tracking echocardiography (3DSTE) was performed in all cTOF patients and controls.

Results
Sixteen out of 26 cTOF patients showed normally directed LV rotational mechanics, while apical and basal LV rotations were in the same clockwise and counterclockwise directions in 7 and 3 cTOF cases, respectively (38%). This sort of LV movement is called as LV rigid body rotation (RBR). The ratio of LV-RBR between etrTOF and pcTOF patients did not differ significantly (33% vs. 43%, p=0.70). Significantly reduced LV apical rotation (5.2±3.7 degree vs. 10.2±4.5 degree, p&lt;0.05) and twist (9.0±3.3 degree vs. 14.6±4.9 degree, p&lt;0.05) could be demonstrated in cTOF patients with normally directed LV rotational mechanics with preserved LV basal rotation regardless of previous procedure. pcTOF patients showed significantly reduced LV apical rotation as compared to that of etrTOF cases (3.2±3.7 degree vs. 7.1±2.5 degree, p&lt;0.05). From the 7 cTOF patients with clockwise LV-RBR, apical and basal LV rotation proved to be −6.8±5.4 degree and −4.9±2.4 degree, respectively with LV apico-basal gradient of 4.3±3.6 degree. The mean LV apical and basal LV rotation of 3 cTOF patients with counterclockwise LV-RBR prove to be −2.1±3.4 degree and 0.2±0.9 degree, respectively with LV apico-basal gradient of 2.5±2.4 degree. Significant correlations could be demonstrated between LV apical rotation and aortic stiffness index (r=−0.55, p=0.03) and aortic distensibility (r=0.52, p=0.04).

Conclusions
Significant LV rotational abnormalities could be demonstrated in cTOF with the high prevalence of LV-RBR. cTOF patients with early total reconstruction proved to have beneficial results. Abnormal physiologic response of LV rotational mechanics to increased aortic stiffness can be detected in cTOF patients without LV-RBR.

Funding Acknowledgement
Type of funding source: None