Heart rate (HR) variability (HRV; beat-to-beat changes in the R-wave to R-wave interval) has
attracted considerable attention during the past 30+ years (PubMed currently lists> 17 000 …

Low heart rate (HR) variability is a risk factor for cardiac mortality in various patient
populations, but it has not been well established whether patients with long-standing …

Heart rate variability (HRV) is a useful noninvasive tool to assess cardiac autonomic
function. The purpose of this study was to (1) compare measures of HRV between …

OBJECTIVES The objectives of this review are to discuss the diversity of mechanisms that
may explain the association between heart rate (HR) variability and mortality, to appraise the …

That elevated heart rate (HR) is a risk factor for cardiovascular morbidity and mortality in
healthy people as well as in patients with cardiac diseases is supported by numerous …

Objectives. This study sought to define the effects of age and gender effects on the normal
range of time domain heart rate variability (HRV) over nine decades in healthy subjects …

Heart rate variability (HRV), the beat-to-beat variation in either heart rate or the duration of
the R–R interval–the heart period, has become a popular clinical and investigational tool …

The dynamical fluctuations in the rhythms of biological systems provide valuable information
about the underlying functioning of these systems. During the past few decades analysis of …

There is a linear relationship between resting heart rate (HR) and mortality in normotensive
and untreated hypertensive individuals. However, it is not clear whether HR is a marker of …

Heart rate variability (HRV), the beat-to-beat variation in either heart rate or the duration of
the RR interval, has become a popular clinical and investigational tool (Task Force of the …