Abstract
Introduction
Left Ventricular (LV) torsion is an important component of LV performance. With the development of speckle tracking echocardiography, it became possible and feasible to measure rotation and twisting with a high degree of accuracy. No standard normal values are defined for peak torsion, although mean values around 10° are found in normal subjects with a slight increase with age.
Purpose
In this study we aimed to evaluate torsion in the different types of severe valvular disease.
Methods
We conducted a retrospective, observational study including patients with severe valvular disease with suitable images for torsion analysis. We included 61 patients (21 with severe aortic stenosis (AS), 20 with severe aortic regurgitation (AR) and 20 with severe mitral regurgitation (MR). Circumferential basal and apical strain was performed, and peak torsion was calculated. Results were compared between groups and were related with echocardiographic parameters, including left ventricle ejection fraction (LVEF).
Results
Mean age was 70.3 ± 13.6 years with a male preponderance (66%). Mean LVEF was within normal range in the aortic valve disease group; no significant difference was found in LVEF between AS and AR patients (57 ± 7.7% vs 55 ± 9.7%, p = 0.57). In comparison with the aortic disease group, MR patients had a reduced LVEF (48 ± 17.3% vs 56 ± 8.7%, p = 0.05). Mean peak torsion was 8.9 ± 5.1° in AS, 12.6 ± 4.9° in AR and 7.9 ± 3.2° in MR (p = 0.004). Comparing with aortic valve disease patients, MR patients had a reduced mean peak torsion (7.9 ± 3.2° vs 10.7 ± 5.3°, p = 0.03). In relation with patients with AS, those with AR had a higher peak torsion (12.6 ± 4.9° vs 8.9 ± 5.1°, p = 0.024) and a higher left ventricle end-diastolic volume (87.3 ± 29.1 mL.m-² vs 64.5 ± 24.9 mL.m-², p = 0.011). Circumferential apical strain showed a negative correlation with peak torsion (r²=0.203, p = 0.006) and with LVEF (r²=0.290, p < 0.001). Peak torsion did not demonstrate any significant correlation neither LVEF nor circumferential basal strain.
Conclusion
LV function and peak torsion are more associated with apical than basal circumferential movement. Aortic valve disease is responsible for LV torsion variations in patients with normal ejection fraction, showing an increase in AR and a reduction in AS. In MR patients a reduced LVEF could entails a decrease in peak torsion.