English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Using a three-compartment model of blood pressure dynamics, we analyzetheoretically the short term cardiovascular variability: how therespiratory-related blood pressure fluctuations are buffered by appropriateheart rate changes: i.e. the respiratory sinus arrhythmia. The buffering isshown to be crucially dependent on the time delay between the stimulus (such ase.g. the inspiration onset) and the application of the control (the moment intime when the efferent response is delivered to the heart). This theoreticalanalysis shows that the buffering mechanism is effective only in the uprightposition of the body. It explains a paradoxical effect of enhancement of theblood pressure fluctuations by an ineffective control. Such a phenomenon wasobserved experimentally. Using the basis of the model, we discuss the bloodpressure variability and heart rate variability under such clinical conditionsas the states of expressed adrenergic drive and the tilt-test during theparasympathetic blockade or fixed rate atrial pacing. From the results of thevariability analysis we draw a conclusion that the control of blood pressure inthe HF band does not directly obtain the arterial baroreceptor input. We alsodiscuss methodological issues of baroreflex sensitivity and sympathovagalbalance assessment.

Buffering blood pressure fluctuations by respiratory sinus arrhythmia may in fact enhance them: a theoretical analysis