Interferences between Baroreflex and Respiration

Summary

Background: The baroreflex is one of the most important short-term cardiovascular autonomic control mechanisms. Its interactions with other reflexes, mainly cardio-pulmonary reflexes, are of paramount importance in controlling heart rate.

Objectives: This study assesses the coupling between baroreflex and respiration during a progressive bicycle mild dynamical exercise.

Methods: The coupling was assessed by symbolic analysis and conditional entropy.

Results: Findings suggested the close relationship between the baroreflex sequences and the phase of respiratory signal and, thus, the interference between baroreflex and cardiopulmonary reflexes.

Conclusions: Indexes describing baroreflex based on spontaneous variability are strongly affected by cardiopulmonary influences.

Keywords

Baroreflex - cardiopulmonary reflexes - symbolic analysis - conditional entropy

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