Characterisation of thigh-based electrocardiography (ECG) across different pathologies

Area of Science:

• Biomedical Engineering
• Cardiology
• Medical Devices

Background:

• Cardiovascular diseases are a leading global health concern.
• Continuous electrocardiographic (ECG) monitoring is crucial for managing cardiovascular conditions.
• Current ECG monitoring methods can be uncomfortable and limit long-term adherence.

Purpose of the Study:

• To assess the feasibility of acquiring ECG signals using a toilet seat interface with dry electrodes.
• To analyze the quality and diagnostic potential of thigh-acquired ECGs compared to conventional methods.
• To explore the application of thigh-based ECGs for patient stratification and disease-specific autonomic pattern identification.

Main Methods:

• 30 hospitalized patients with diverse cardiovascular conditions were enrolled.
• ECG signals were acquired simultaneously from a toilet seat interface (posterior thighs) and conventional limb leads.
• Analysis included ECG morphology, heart rate variability (HRV) metrics, and principal component/hierarchical clustering for disease-related grouping.

Main Results:

• Thigh-acquired ECGs demonstrated clear P-QRS-T complexes with preserved morphology, enabling reliable HRV analysis.
• Patients with post-surgical aortic repair showed ECG profiles closest to the normal cluster, while aortic stenosis (AS) patients were most distant.
• Disease-specific autonomic patterns were identified: higher HRV in tricuspid/mitral valve disease, reduced parasympathetic indices in aortic valve disease.
• Clustering analysis differentiated conditions with severe hemodynamic disruption (e.g., PS, AS) and identified overlapping groups for Acute Coronary Syndrome, Unstable Angina, and Ascending Aortic Aneurysm.

Conclusions:

• Unobtrusive thigh-based ECG monitoring via a toilet-seat interface is feasible.
• This method allows reliable ECG signal acquisition and heart rate variability analysis.
• The approach shows potential for preliminary patient stratification and future home-based cardiovascular screening and telemedicine applications.