Insights into Left Ventricular Function from the Time Course of Regional and Global Rotation by Speckle Tracking Echocardiography

Background: Description and quantification of regional left ventricular (LV) rotation and the time course of LV rotation might provide further insight into LV function. Methods: The study comprised 60 healthy volunteers (age 39 ± 15 years, 31 men) in whom complete global and regional LV rotation could be assessed at both the basal and apical LV level with speckle tracking echocardiography, using QLAB advanced quantification software version 6.0 (Philips, Best, The Netherlands). Results: At the LV basal level, a brief counterclockwise rotation from aortic valve opening until 25% ejection was seen in the anterior segments (anterior, anteroseptal, anterolateral) only. Clockwise rotation in the anterior segments at the basal level was decreased as compared to the posterior segments (inferior, inferoseptal, inferolateral) from 25% ejection until aortic valve closure. At the LV apical level, all segments showed a brief clockwise rotation during the isovolumic contraction phase. Also, at this level there were no differences in regional LV rotation at any other moment during the cardiac cycle. There was a marked de-rotation from the moment of maximal rotation until E-peak at the LV basal level (79 ± 18%) whereas de-rotation during this interval was less pronounced at the LV apical level (55 ± 21%). Only at the LV basal level significant linear relationships were seen between the E/A ratio and de-rotation extent and velocity from mitral valve opening until E-peak (R²= 0.42 and R²= 0.40, respectively, both P < 0.001). Conclusion: In the normal human heart significant regional differences in LV rotation and de-rotation exist.