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Jeremy E. Kaslow, MD
Heart Rate
Variability (HRV)
Heart Rate Variability (HRV): Welcome
The Autonomic Nervous System
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Your nervous system is divided into a nervous system that controls voluntary movements (mainly muscles) and the Autonomic Nervous System (ANS). The ANS regulates individual organ function and homeostasis, and for the most part is not subject to voluntary control. The ANS is divided into two separate divisions called the Parasympathetic Nervous System (think rest and digest) and the Sympathetic System (think fight or flight).
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Most of your organs are controlled by both divisions of the ANS and the influence is usually opposing (e.g. the vagus slows the heart; the sympathetic nerves increase the heart’s rate and contractility). In physiological terms, the parasympathetic system is concerned with conservation and restoration of energy. It causes a reduction in heart rate and blood pressure, and facilitates digestion and absorption of nutrients, and consequently the excretion of waste products.
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In contrast your sympathetic system enables you to be prepared for mobilization e.g., for flight or fight. Sympathetic responses include an increase in heart rate, blood pressure and cardiac output, a diversion of blood flow from the skin and organs to those supplying skeletal muscle, increased pupil size, bronchial dilation, contraction of sphincters and metabolic changes such as the mobilization of fat and glycogen for immediate energy.
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It is important to realize that the tissue between individual cells is where the ANS ends. This connective issue bathes every cell and regulates their function. ANS messages travel both directions and become a dialogue between tissues throughout the body and your central nervous system (CNS). Thus, your ANS controls immune support, nutrient delivery, detoxication, blood flow, and oxygenation (via vasodilation/constriction). Monitoring the state of your ANS thus becomes a powerful tool that guides us toward optimizing cellular function and thus your overall health, even when you seem to “feel fine.”
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Using Heart Rate Variability (HRV)
To Measure Your Autonomic Nervous System
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Our Nerve-Express program provides a “fingerprint” of your ANS based on HRV analysis. Nerve-Express is the only system that enables precise recognition and classification of 74 ANS states with a corresponding qualitative description for each one. The algorithms used by Nerve-Express have been developed and tested for over twenty years in studies involving more than twenty thousand patients.
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HRV analysis is based on measuring variability in heart rate (specifically, variability in intervals between your heart beat). It is a measurement of the interaction between sympathetic (i.e., “fight or flight” energy mobilization) and parasympathetic (i.e., the opposite of the sympathetic activity or “relaxation” response) activity in autonomic functioning (i.e., the nervous system that controls the heart, intestines, and other organs).
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A proper evaluation requires measurements in at least two different situations. Nerve Express uses a popular method to provoke an autonomic response – stand upright from a lying (supine) position. Any physical or mental dysfunction will reflect as an inadequate ANS response. in the vagal tone upon standing (Ideally you would want a . . . . . . . .. ) Those with an ANS component to their GI distress will show a decrease in vagal tone while lying down (ideally you would want . . . . . .) to an insufficient tone (< 0) when standing upright (Ideally you would want a . . . . . in vagal tone upon standing.
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Why use the HRV?
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Measurement HRV provides a non-invasive method to obtain reliable and reproducible information on the autonomic nervous system’s influence on the heart and has become an important tool for risk assessment. Measurement of HRV may also be used to evaluate the effects of drug treatments in these patients.
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Research has shown that emotions are reflected in our heart rhythm patterns. The analysis of Heart Rate Variability (HRV), or heart rhythms, is recognized as a powerful measure that reflects heart-brain interactions and autonomic nervous system dynamics, which are particularly sensitive to changes in the emotional state. Clinical research identifies HRV as a key indicator of preventable stress and shows correlation with a broad range of related health problems. For example, studies have shown that smokers have increased sympathetic and reduced vagal activity as measured by HRV analysis. HRV is reduced following acute ingestion of alcohol suggesting sympathetic activation and/or parasympathetic withdrawal.
Heart Rate Variability (HRV): Welcome
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