Does upright exercise alter left ventricular longitudinal motion in healthy male endurance athletes?
In healthy male endurance athletes, upright exercise significantly increases mitral annular motion due to a decrease in axial end-systolic length, equalizing septal and lateral excursion at peak exercise.
The aim of the present study was to quantify the left ventricular (LV) longitudinal motion during exercise at rest and during upright exercise in 24 healthy male endurance athletes. By using M-mode and two-dimensional echocardiography, the relative mitral annular motion and the absolute LV longitudinal axis was measured at end-diastole and end-systole at rest and during exercise. From rest to peak exercise at a heart rate of 160 beats per minute (bpm) the mitral annular motion increased in the septal and lateral annular borders by 68% and 49% respectively. At rest, mitral annular excursion was significantly (13%) higher in the lateral than in the septal wall but at peak exercise at a heart rate of 160 bpm there was no difference between the septal and lateral annular motion. The total end-diastolic LV axial length did not increase from rest to peak exercise. In conclusion, during upright exercise, mitral annular motion increased significantly with no difference between the septal and lateral annular excursion at peak exercise. The absolute increase in mitral annular motion during exercise was explained by a decrease in axial end-systolic length.
Sundstedt et al. (Thu,) studied this question.