Effects of physical training on autonomic cardiac modulation in hypertension: assessment by heart rate variability analysis

摘要

The autonomic nervous system is the primary mechanism for short-term blood pressure (BP) regulation on a beat-by-beat basis. In normal physiological conditions, very precise control of BP levels is achieved through a complex combination between central neural and reflex influences, leading to a continuous modulation of efferent sympathetic and parasympathetic nerve activity and the associated activity of neuro-hormonal systems primarily regulated by the hypothalamus. Several studies using direct methodologies for the assessment of overall and regional sympathetic cardiovascular (CV) drive have demonstrated the association between chronic activation of the sympathetic nervous system and the development, establishment and progression of essential hypertension. Most studies supporting this concept have consistently confirmed an increase in central sympathetic drive in essential hypertension through the use of dedicated techniques for the direct assessment of sympathetic activity (that is, regional nora-drenaline spillover or the direct recording of efferent postganglionic muscle sympathetic nerve activity via microneurography).