HEART rate variability biofeedback for long COVID symptoms (HEARTLOC): protocol for a feasibility study

Area of Science:

• Cardiology
• Neurology
• Rehabilitation Medicine

Background:

• Long COVID (LC) affects up to 14% of individuals post-SARS-CoV2 infection, presenting diverse symptoms.
• Many LC symptoms, including fatigue, palpitations, and brain fog, are linked to autonomic nervous system (ANS) dysregulation (dysautonomia).
• Current rehabilitation strategies for LC are evolving, necessitating exploration of novel therapeutic approaches.

Purpose of the Study:

• To assess the feasibility of a 4-week heart rate variability biofeedback (HRV-B) intervention for LC patients.
• To estimate the efficacy of HRV-B, combined with slow diaphragmatic breathing, in improving symptoms associated with dysautonomia in LC.
• To gather qualitative user feedback on the technology and intervention's practicality in a home setting.

Main Methods:

• A 4-week feasibility study involving 30 adult LC patients with palpitations or dizziness and abnormal NASA Lean Test results.
• Participants engaged in a standardized slow diaphragmatic breathing program with HRV-B using a chest strap and smartphone application twice daily.
• Quantitative data collected included HRV metrics, validated questionnaires (e.g., COVID-19 Yorkshire Rehabilitation Scale, Composite Autonomic Symptom Score), and quality of life measures (EQ-5D-5L).

Main Results:

• The study is designed to analyze quantitative data using standard statistical tests for correlation and significant difference.
• Qualitative feedback will provide insights into the user experience and technological feasibility.
• Results will inform the potential of HRV-B as a therapeutic tool for autonomic dysfunction in Long COVID.

Conclusions:

• HRV-B, coupled with controlled breathing, presents a potential non-pharmacological intervention for managing Long COVID symptoms linked to dysautonomia.
• This study's findings will contribute to evidence-based rehabilitation strategies for post-viral syndromes.
• Further research may explore larger cohorts and longer intervention periods to confirm efficacy.