Heart Rate Variability (HRV) is already used in many research areas as a noninvasive method for risk stratification. But what is the connection between the HRV and a stroke?

Introduction 

EA stroke is now the world’s leading cause of disability and the second most common cause of death after a heart attack. A stroke is the result of vascular occlusion or hemorrhage in the brain. It is associated with high mortality and serious consequences. During a stroke, the nerve cells in the brain get too little oxygen and nutrients. Because of that they die. This can lead to a persistent failure of the central nervous system functions and disorders such as speech disorders and paralysis.

That’s why everybody wants an inexpensive and effective non-invasive method for risk stratification and treatment. According to Lees and colleagues (2018), the Heart Rate Variability (HRV) is a non-invasive measure of the function of the autonomic nervous system. Their dynamic nature can provide many clues about the risk of a stroke.

Research

Lee’s research group from Australia examined in their systematic review the predictive power of HRV in terms of the occurrence and monitoring of the therapeutic success. Therefore the researchers investigated the results of 22 worldwide studies on strokes and HRV.

The review showed that short-term HRV measurements need to be further investigated due to the small number of studies to clearly demonstrate their prognostic power. However, the studies indicate that both, the time-dependent HRV parameters, such as SDNN, and the frequency-dependent HRV parameters, such as low-frequency or high-frequency, are changed in patients with a stroke compared to healthy patients. Hence this field of research represents an area with many future perspectives.

Results

Long-term HRV measurements show that there are differences in the time and frequency-dependent HRV parameters between healthy patients and patients with a stroke. Furthermore, Poincare-plots and circadian oscillations of HRV have been identified as predictive factors. The post-stroke complications also demonstrated the validity of HRV and some parameters such as LF/HF ratio.

The current state of knowledge offers evidence for the usefulness of HRV as a prognostic marker for strokes. Various HRV parameters act as biomarkers for stroke occurrence and can also identify many of the complications that occur after such an event. It is possible that some serious consequences of a stroke, such as motor impairment and death, can be better estimated. The functional effects can also be reliably predicted using frequency-dependent parameters such as low-frequency and high-frequency (Lees et al., 2018).

Conclusion

HRV is not only a useful measurement tool in many treatment strategies, but also a good way to detect health warnings on time.

Literature

LEES, T., SHAD-KANEEZ, F., SIMPSON, A. M., NASSIF, N. T., LIN, Y. & LAL, S. 2018. Heart Rate Variability as a Biomarker for Predicting Stroke, Post-stroke Complications and Functionality. Biomark Insights, 13, 1177271918786931.

Image source

Adobe Stock Photo: freshidea – Datei Nr. 37726081