For the past decade heart rate variability (HRV) analysis has gained a significant interest within medical researchers and health oriented professionals. The amount of research papers on HRV ( heart rate variability)published for the past 5-10 years has grown hundreds times. Nowadays it is hard to find any area of human health studies where HRV ( heart rate variability)would not be considered. There is growing number of health conditions where HRV ( heart rate variability)was found helpful in diagnostic process. Besides HRV method is used in general health assessment of healthy subjects. What is the history of HRV ( heart rate variability)? Why did it gain such high interest? What kind of equipment is available now for HRV analysis? Methods of heart rate variability Analysis. Methods of HRV ( heart rate variability) analysis were conceptualized in 60s of last century. The success in space medicine research has ignited this area of biomedical studies. First manned space flights forced biomedical scientists to develop means to monitor health condition of space crew members. It was impossible to equip spaceships with oversized medical equipment existing at those times. The scientists were forced to design new methods and tools for health assessment which would be as efficient as the existing ones but not requiring to have medical professionals on board to perform data collection and analysis and very compact.
Electrocardiograph (ECG) was found as one of the best technologies suitable for this purpose. ECG measures electric activity of the heart. ECG analysis was well-known at that time. However while analyzing long ECG recordings researchers have noticed that heartbeat intervals keep fluctuating beat-by-beat all the time. Initially researchers were trying to filter those fluctuations out to get averaged heart rate values. However later they wondered if there is any physiologically meaningful information in those fluctuations. Thus new area of biomedical research emerged called HRV ( heart rate variability) analysis. In 1996 a special Task Force of the European Society of Cardiology and North American Society of Pacing and Electrophysiology published first world standards for measurement, analysis, physiological interpretation of HRV and recommendations for its clinical use. After that the amount of HRV ( heart rate variability) research started growing fast. There are many evidences of HRV ( heart rate variability) changes in patients with cardiovascular diseases. Why HRV has become a non-specific marker of development of such different types of health conditions? The answer is because HRV is mainly a reflection of current state of the autonomic nervous system (ANS) function. The ANS controls practically all body’s vital organs and functions.