CARDIOVASCULAR MALADAPTIVE CHANGES DURING EXERTION IN YOUNG HYPERTENSIVE PATIENTS

Background: The ability of the heart to adequately respond to the increase of metabolic demand during exertion relies on several adaptive changes leading to augmented cardiac output without any rise of filling pressures. The impairment of these compensatory mechanisms, as found in various heart diseases including systemic hypertension, can translate to reduced functional capacity. In this study, we sought to investigate the cardiovascular adaptation to exertion in a cohort of asymptomatic hypertensive patients, with the aim to identify early cardiac abnormalities. Methods: We enrolled 54 subjects including 30 patients (45.1±11.9 years, 19 males) and 24 age-matched healthy controls (44.4±9.6 years, 14 males). A comprehensive echocardiographic and vascular evaluation, implemented by speckle-tracking imaging (STI) and echo-tracking analysis to assess, respectively, myocardial deformation and arterial stiffness, has been performed at rest and during exertion (100 W). Results: Hypertensive patients showed higher E/E' (p=0.001) at peak exercise (p=0.001) than controls. Global longitudinal strain (GLS) remained substantially unchanged (p=0.761) from rest to peak stage in patients, whereas it increased in controls (p=0.009). LV untwist increased in both groups (p=0.031 and 0.015 in patients and controls, respectively), with a minor increase in patients than in controls (p=0.029 between groups, at peak stage). Beta index and pulse wave velocity (PWV) were higher in patients than in controls, at rest and during exertion (respectively, p=0.0046 and 0.001). Conclusions: Exercise echocardiography implemented by STI and echo-tracking may allow the early detection of cardiovascular maladaptive changes to exercise, including impaired longitudinal function reserve and increased arterial stiffness, in asymptomatic hypertensive patients. These findings highlight the importance of ventricular-vascular interplay for a physiological cardiac function. Moreover, these results, if confirmed in a larger cohort, may be useful for an early detection of myocardial dysfunction in hypertension and for an early begin of cardioprotective therapy.