Objectives .– To study the feasibility of quantifying left ventricular (LV) function by 2D-speckle tracking of myocardial deformation during exercise echocardiography in normal subjects.

Background .– Accurate assessment of LV functional reserve during stress testing is challenging. For this purpose, the value of LV ejection fraction is limited. 2D-speckle tracking allows accurate quantification of LV regional function at rest. However, no study has evaluated the exercise-induced changes in myocardial deformation in normal subjects.

Methods .– Fifty-three consecutive normal subjects underwent quantitative assessment of LV function using 2D-speckle tracking at rest and during a semi-supine graded exercise echocardiography. All strain and LV rotation parameters were measured at rest and at exercise to assess longitudinal strains in apical views and radial strains in parasternal short-axis view.

Results .– During test, LV ejection fraction increased significantly from rest to peak exercise (64.3 ± 5.6% vs 74.6 ± 6.4%; P < 0.0001) whereas LV end-systolic volume decreased ( P < 0.001). All strains parameters of myocardial deformation (longitudinal 20.1 ± 2.8% to 24.6 ± 3.6%, P < 0.0001, radial 48.4 ± 12.8% to 60.3 ± 10.2%, P < 0.001) increased during exercise. Changes in LV ejection fraction during exercise were well correlated with changes in longitudinal function (R ² = 0.379, P = 0.018). LV apex rotation and rotation rate also increased during test (11.5 ± 3.8 to 21.8 ± 2.5 deg, P < 0.0001 and 122.2 ± 47.7 to 209.5 ± 41.9 deg s-1; P = 0.0001 respectively for rotation and rotation rate). Intra- and inter-observer agreements for strain measurements were good. The variability between observers ranged from 0.5 to 6.4%.

Conclusion .– Evaluation of LV function by 2D-speckle tracking during exercise is feasible. This method can thus be used to accurately assess LV functional reserve during stress.