Heart rate variability (HRV) is generated by the interaction of multiple regulatory mechanisms that operate on different time scales. This article examines the regulation of the heart, the meaning of HRV, Thayer and Lane’s neurovisceral integration model, the sources of HRV, HRV frequency and time domain measurements, Porges’s polyvagal theory, and resonance frequency breathing. The medical imp...

The effect of one-year physical training on heart rate variability in older adults was evaluated in 14 healthy men (age > 55 year). Measures of heart rate variability were obtained in both time and frequency domain. Tenminute ECG recordings were made in supine position and in standing position. A progressive climbing exertion test till exhaustion was performed to estimate maximal oxygen consump...

Introduction Familial Mediterranean fever (FMF) is characterized by acute and recurrent attacks of fever and polyserositis. It is associated with conduction disturbances and rhythm abnormalities. Heart rate variability (HRV) is the term used to indicate the fluctuation in cardiac frequency over time. HRV analysis is used to evaluate the condition of the autonomous nervous system, which regulate...

Following a previous investigation on the therapeutic effects of Extremely Low Frequency in pulsed form Pulsed Extremely Low Frequency (PELF) [1] this research explores the possibility of detecting the effects of PELF on the biological system by the use of the Heart Rate Variability (HRV) analysis. There is no overall change in HRV in presence of very weak less than 25 μT PELF. However when the...

Background: Heart rate variability is actually a misnomer for R to R variability in cardiac cycle. Variation in successive cycle length is called the heart rate variability (HRV). Head-up tilt is a model of studying cardiovascular haemodynamics, which refl ects in heart rate variability (HRV). Objectives: To study the effect of 10° and 70° head-up tilt on HRV. Materials and methods: The study w...

BACKGROUND Heart rate variability is actually a misnomer for R to R variability in cardiac cycle. Variation in successive cycle length is called the heart rate variability (HRV). Head-up tilt is a model of studying cardiovascular haemodynamics, which reflects in heart rate variability (HRV). OBJECTIVES To study the effect of 10 degrees and 70 degrees head-up tilt on HRV. MATERIALS AND METHO...

A common cause of death in end-stage renal disease (ESRD) patients on dialysis is sudden cardiac death (SCD). Compared to the general population, the percentage of cardiovascular deaths that are attributed to SCD is higher in patients treated by dialysis. While coronary artery disease (CAD) is the predominant cause of SCD in dialysis patients, reduced heart rate variability (HRV) may play a rol...

In this paper are presented the current results of scientific research of heart rate variability (HRV) analysis based on digital electrocardiograms (ECG). This analysis is a non-invasive and effective technique to reflect the autonomic nervous system regulation of the heart. HRV is used to diagnose and estimate of alterations in heart rate by measuring the variation of RR intervals (time interv...

Introduction Familial Mediterranean fever (FMF) is characterized by acute and recurrent attacks of fever and polyserositis. It is associated with conduction disturbances and rhythm abnormalities. Heart rate variability (HRV) is the term used to indicate the fluctuation in cardiac frequency over time. HRV analysis is used to evaluate the condition of the autonomous nervous system, which regulate...