Work

Structural identifiability of single-beat estimation of the ventricular end-systolic pressure–volume relationship

Year: 2026

Type: article

Abstract: Single-beat (SB) approaches for estimating the end-systolic pressure–volume relationship (ESPVR) from a single pressure–volume ( P – V ) loop are widely used in experimental and clinical research, yet their structural foundations remain insufficiently formalized. ESPVR is a phenomenological construct defined from multi-beat (MB) measurements across varying loading conditions, and its SB estimation therefore constitutes an inverse problem. We show that SB estimation of the ESPVR slope ( E es ) is intrinsically underdetermined, as a single P – V loop provides fewer independent constraints than unknown parameters. Consequently, any SB method requires auxiliary information to achieve mathematical closure. Using nine high-fidelity P – V loops obtained during vena cava occlusion in a porcine model as a demonstrator dataset, we quantify (i) the sensitivity of the MB-derived E es,MB to the selection of the P – V loop subset, and (ii) the sensitivity of E es to representative classes of auxiliary information. The analysis reveals that auxiliary information based solely on population-averaged normalized elastance curves is structurally inconsistent with the MB reference definition. Among the examined candidates, the normalized elastance at the onset of ejection ( E N,dia ) exhibits the most favorable structural properties, combining low sensitivity of E es to estimation errors with a strong empirical association captured by regression modeling. By reframing SB estimation of ESPVR as a structural identifiability problem rather than a purely numerical task, this study establishes criteria for physiologically consistent auxiliary relations and highlights the necessity of large, standardized MB databases for future data-driven SB methodologies.

Source: Biomedical Physics & Engineering Express

DOI: 10.1088/2057-1976/ae5f9b

Authors: Fabijan Lulić, Severino Krizmanić, Igor Vodopija, Zdravko Virag

Institutions: University Hospital Centre Zagreb, University of Zagreb, Faculty of Mechanical Engineering and Naval Architecture in Zagreb

Language: English

Topic: Cardiovascular Function and Risk Factors

Subfield: Cardiology and Cardiovascular Medicine

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: hybrid

Estimated APC paid: $2,400