Does stroke volume influence heartbeat evoked responses?

Area of Science:

• Neuroscience
• Cardiology
• Biomedical Engineering

Background:

• Heartbeat-evoked responses (HERs) are neural signals influenced by cardiac activity.
• Understanding the relationship between cardiac parameters and HERs is crucial for accurate neuroimaging analysis.
• Current knowledge on how stroke volume affects HERs is limited.

Purpose of the Study:

• To investigate the relationship between stroke volume and HER amplitude.
• To assess the impact of cardiac artifact correction on HERs.
• To identify reliable proxies for stroke volume in magnetoencephalography (MEG) studies.

Main Methods:

• Simultaneous measurement of stroke volume using impedance cardiography and HER amplitude using magnetoencephalography (MEG) in 21 participants.
• Analysis of beat-to-beat fluctuations in HER amplitude in relation to stroke volume.
• Evaluation of the necessity and effectiveness of Independent Component Analysis (ICA) for cardiac artifact correction.
• Assessment of interbeat intervals and ECG amplitude as potential stroke volume proxies.

Main Results:

• HER amplitude co-fluctuated with stroke volume on a beat-to-beat basis when cardiac artifacts were not corrected.
• ICA correction tailored to cardiac artifacts is essential for accurate HER analysis.
• Interbeat intervals and ECG amplitude were found to be sensitive to stroke volume fluctuations, serving as potential proxies.
• Interindividual differences in stroke volume were detectable in MEG data, though their heartbeat-locked nature remains uncertain.

Conclusions:

• The study demonstrates a beat-to-beat link between stroke volume and HERs, contingent on proper artifact correction.
• Simple cardiac parameters can be utilized as effective proxies for stroke volume in MEG.
• The findings challenge existing assumptions regarding the direct relationship between stroke volume and HERs, emphasizing the need for artifact-aware analysis.