Related Experiment Video
Updated: Jun 15, 2026

Simultaneous Recordings of Cortical Local Field Potentials, Electrocardiogram, Electromyogram, and Breathing Rhythm from a Freely Moving Rat
Published on: April 2, 2018
Synchronization between cardiac and respiratory rhythms in healthy subjects and patients
Masaki Shimane1, Yutaka Tomita, Toshihiro Shinbo
1Department of Respiratory Medicine, Kitasato University Kitasato Institute Medical Center Hospital 364-8501, Saitama, Japan.
Abstract:
Synchronization between cardiac and respiratory rhythms may be important for oxygen transport to tissues. The aim of this study was to investigate the synchronization between cardiac and respiratory rhythms. We evaluated the rhythms in 12 healthy males and 24 patients. The incidence rates of heart beats were obtained in each time interval relative to the initiation time point of inspiration. A simple index of timing variability of heart beats was defined. When the variability is large, the link between cardiac and respiratory rhythms was considered to be strong. The variability value of patients with disorder in the autonomic nervous system was larger than that of healthy subjects (p < 0.05). The variability of patients on controlled ventilation was lower than that of healthy subjects (p < 0.01), whereas the value on cardiac pacemaker did not differ from healthy subjects. In conclusion, the synchronization between cardiac and respiratory rhythms was confirmed, and it is suggested that the synchronization is enhanced when feed-back signals from respiratory movement to respiratory center were decreased.
Related Concept Videos
Pulse rhythm
Conversely, an irregular pulse pattern is termed dysrhythmia, stemming from disruptions in cardiac muscle...
Electrophysiology of Normal Cardiac Rhythm
Respiratory Volumes and Capacities I
Assessment of Ventilation II: Respiratory Depth and Rhythm
Respiratory depth measures the volume of air inhaled or exhaled during a breath. It can vary from shallow to deep and typically remains consistent when a person is at rest or asleep. Occasionally, individuals will automatically inhale deeply, known as sighing, which inflates the lungs with more air than normal breathing.
To assess respiratory depth, observe the degree of chest excursion or movement:
Special considerations while measuring oxygen saturation
Ensuring accuracy in vital sign recordings while prioritizing patient comfort and minimizing anxiety is important.
Correlation between ECG and Cardiac Cycle
A cardiac action potential originates in the SA node and spreads throughout the atria and the AV node in approximately 0.03 seconds. This results in the P wave in an ECG and triggers atrial contraction. The action potential is then briefly slowed at the AV node, allowing the atria to contract and fill the ventricles with blood before...
