HRV IN DIFFERENT MEDICAL AREAS

a) Cardiology and cardiovascular diseases
A reduction of vagal tone is found to be associated with acute myocardial infarction (so HRV can be used as a prognostic tool in post-infact period). HRV has a high association with the risk for sudden cardiac death, and arrhythmic complications (4). Diminished vagal activity is found in patients with coronary artery disease and essential hypertension. After heart transplantation the allograft rejection can be predicted by decreased total spectral power.

b) Neurology
HRV reflects autonomic dysfunction of central origin in patients with parkinsonism, spinocerebellar degeneration, Shy - Drager syndrome, multiple sclerosis, chronic alcoholism, Guillan - Barre syndrome, quadriplegia etc.

c) Diabetes mellitus
Diabetic cardiomiopathy is substantially decreasing HRV. As this decrease is often preceding clinical symptoms, HRV can be used for early prediction of the diabetic pathology (5), especially in children.

d) Glomerulonephrites with renal insufficiency
Decrease of vagal tone was found in uremic patients, revealed namely by the diminution of the short waves-associated spectral power.

e) Pharmacological influence
Calcium channel blockers (as atenolol f.e.), beta-blockers (as diltiazem f.e.), tranquilisers, relaxants, scopolamine (vagomimetic), etc. are increasing the time as well as the frequency-domain HRV measures. Contrary, atropine is decreasing vagal activity (2). It is interesting to note, that nifidipine (Ca-blocker) has not effect upon HRV.

f) Toxicology
HRV analysis can reveal the severity of autonomic dysfunction caused by environmental neurotoxic agents as organic solvents, pesticides, nitrates, organophosfates, leads etc.

g) Work-related stress
Vibratory tool operations, inconvenient regimes of work and rest, dust of different kinds, ergonomical disadvantages, overload, bad psychological microclimate etc. can decrease HRV. This is used for their quantitative assessment and control (3).

h) Medical ecology
Ecological hazard needs to be evaluated not only by measuring of the level of ecological noxes, but also by the impact they have upon common functional status of the population living in ecologically contaminated areas. This can be done, before all, by following up the chronically increased sympathetical tone by HRV measurements.

i) Sport
The status of overtraining as well as the effect of relaxation procedures and the use of forbidden medicaments (doping) can be successfully controlled by HRV.

j) Applied psychology
By multiple step regression analysis is found that phenomena as depression, burnout, lack of social support, uncontrolled locus of control, bad family or social relations etc. are increasing the long waves spectral power and decreasing the total spectral power.

k) Unconventional medical treatments
The effect of manual therapy, traditional Chinese therapies, aromatherapy, massages, sauna, auto gene training, yoga, Silva method etc. is difficult to be assessed without following their impact upon common functional status, which is reflected by HRV.

l) Transport, army and cosmic medicine
All these professions or activities presuppose a high level of health reserves and adaptation capacities. It was found, that the physical as well as the mental effort (6) required in these cases can be reliably evaluated by HRV measurement.

m) Health (life) insurance
Recently some attempts to use HRV as a predictor of overall health risk (as a factor influencing insurance conditions) are done in Norway and Japan.

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