학술논문

P873Assessment of left ventricular twist and torsion in elite athletes using speckle tracking echocardiography
Document Type
Academic Journal
Source
European Journal of Echocardiography. Dec 01, 2011 12(suppl_2 Suppl 2):ii125-ii155
Subject
Language
English
ISSN
1525-2167
Abstract
Left ventricular (LV) contraction is the result of a complex three-dimensional deformation of the heart during systole. In addition to longitudinal shortening and radial thickening, LV twist motion evolved by apical counterclockwise and basal clockwise rotation is a crucial element in effective LV contraction. The aim of our study was to analyze LV torsion dynamics by speckle tracking echocardiography in elite athletes and healthy sedentary volunteers as negative controls. Twenty elite athletes in kayaking, canoeing, or rowing (age: 22.4±3.3 years) and eleven healthy, regularly not exercising volunteers (age: 26.4±4.5 years) underwent cardiac MRI, as well as conventional and speckle tracking echocardiography. LV volume and mass indices and ejection fraction (LVEF) were determined by MRI (Philips Achieva 1.5T, Dual Nova HP). Beside basic echocardiographic evaluation, LV peak systolic rotations were also measured in parasternal short-axis images by speckle tracking echocardiography at a frame rate of 60-80 frames/s (Philips iE33). LV twist was defined as the net difference of LV rotations at the basal and apical planes, while LV torsion was defined as LV twist normalized for LV end-diastolic length. Analysis of the datasets was performed using QLAB, CMQ, software version 8.0. Our results indicated significantly higher LV septal (SWT) and posterior wall thickness (PWT), LV end-systolic volume (LVESV), LV end-diastolic volume (LVEDV) and LV mass indices in elite athletes compared to sedentary volunteers (SWT: 12.7±0.4 mm vs. 11.2±0.3 mm, PWT: 11.6±0.3 mm vs. 9.0±0.5 mm, LVESV index: 61.2±5.4 ml/m vs. 38.4±2.7 ml/m, LVEDV index: 141.9±12.5 ml/m vs. 99.1±3.6 ml/m, LV mass index: 105.9±8.8 g/m vs. 70.1±2.4g/m, mean±SEM, p<0.05). Analysis of the LV torsion dynamics showed significantly higher LV twist and torsion in the elite athlete group compared to the controls (LV twist: 7.4±0.6° vs. 6.0±0.4°; LV torsion: 0.8±0.07°/cm vs. 0.7±0.03°/cm; mean±SEM, p<0.05). In conclusion, speckle tracking echocardiography is a reliable method for measuring LV twist and torsion, and adds valuable information to the assessment of LV systolic function. Higher LV twist and torsion in elite athletes might contribute to their increased functional reserve capacity.