Background: Aim of our study was to evaluate the exercise-induced changes in left ventricular (LV) mechanics and arterial stiffness (AS), assessed by use of 2D-strain and echo-tracking, in young patients affected by essential hypertension (EH) and in age-matched healthy subjects. Methods: 19 asymptomatic patients with EH (mean age 38±7 years) and 11 healthy controls (mean age 37±1 years) underwent echocardiographic and carotid ultrasonographic study during a semisupine bicycle exercise test. An incremental exercise protocol with an increase of 25 W every 2 minutes up to 100 W was employed. Echocardiographic and carotid ultrasonographic images were acquired at rest, 50 W, 100 W and during recovery. 2D strain analysis was performed, offline, by use of a dedicated software (GE, EchoPac) and LV global longitudinal strain (GLS) as well as basal/apical rotations and twist were measured. AS parameters (β and pulse wave velocity [PWV]) were obtained by use of an echotracking software (Aloka, Japan). Results: Standard echocardiographic parameters were comparable between groups. At baseline patients showed lower values of GLS compared to healthy subjects (-19.2±1.9 vs -20.8±2.5, p ns); at 50 W GLS increased in both groups, but the increase of GLS was significantly lower in patients than in controls (-19.9±2.3 vs -22.3±2; p = 0.01), whereas no significant differences were observed at 100 W and during recovery, Figure. Apical rotation and twist increased during exercise in both groups with higher values in patients than in controls, particularly at 50 W (10.8±5.5 vs 6.2±2.5; p = 0.02 and 16.0±3.1 vs 13.2±4.1; p = 0.04, respectively). No significant differences between groups were observed with regards to basal rotation. Furthermore, patients showed, at baseline, higher values of β and PWV than healthy subjects (6.4±2.6 vs 4.4±1.5; p = 0.01 and 5.7±1.1 vs 4.5±0.9; p <0.001, respectively); AS parameters increased throughout the exercise in both groups, with a greater rise, at 50 W, in patients than in controls (β 6.4±2.1 vs 4.8±1.4; p = 0.009. PWV 6.1±0.9 vs 4.8±0.8; p<0.001), whereas no significant differences were found at 100 W and during recovery. Conclusions. Through the combined use of 2D strain and echotracking it is possible to better understand the mechanisms of adaptation of the cardiovascular system to physical effort in healthy subjects and, particularly, in patients with EH. In this respect, LV twist may play a particular compensatory role to both impaired systolic longitudinal function and increased arterial stiffness in order to preserve stroke volume during exercise.
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