Background
Left ventricular (LV) torsion has been proposed as a sensitive index for LV diastolic function. We hypothesized that the LV diastolic untwist rate evaluated by two-dimensional ultrasound speckle tracking imaging might reflects the LV diastolic dysfunction.
Methods Echocardiography was performed in 85 patients. Two groups were studied. 37 patients have normal LV diastolic function. 48 patients have diastolic dysfunction. To assess LV torsion, LV rotation data was acquired at apical and basal short-axis planes with speckle tracking software. LV torsion was defined as the net deference of LV rotation between the apex and base planes. Diastolic untwist rate was estimated by diastolic torsional deformation slope during the early relaxation period. Systolic torsional dynamics were assessed by minimal torsion (peak negative clockwise torsion in early systole) and maximal torsion (peak positive counterclockwise torsion).
Results Diastolic untwist rate was significantly different between two groups (-1.24짹0.52째/ms in normal diastolic function group vs. -0.98짹0.36째/ms in diastolic dysfunction group, p<0.05). Maximal torsion was significantly different between two groups (28.3짹9.3째 vs. 23.8짹8.6째, p<0.05). Minimal torsion was not different between two groups (-3.4짹1.8째 vs. -2.7짹2.5째, p=0.14). LV ejection fraction was not deferent between two groups (63.7짹6.0% vs. 61.9짹10.7%, p=0.36).
Conclusion Diastolic untwist rate measured by by two-dimensional ultrasound speckle tracking imaging may reflects the LV diastolic dysfunction.