Cardiac Hemodynamic Status: An Interpretable One-Look Windkessel Index of Arterial Health

Objective: Cardiovascular assessment typically relies on fragmented single-parameter measures that fail to capture the coordinated interplay between cardiac output (CO), systemic vascular resistance (SVR), and arterial compliance (AC). The Cardiac Hemodynamic Status (CHS) was developed as a practical index integrating these parameters into a single “one-look” assessment of arterial health suitable for bedside monitoring. Approach: CHS was represented as a physiologically scaled vector in CO-SVR-AC space, yielding magnitude (CHSmag) and inclination angle (CHSθ) coordinates. Healthy aging simulations (HA Sim, n=4374), aneurysm simulations (AA-Sim, n=8748), and two young in-vivo cohorts (YH-Vivo, n=140; UY-Vivo, n=12) were analyzed. Group differences were assessed using ANOVA/Tukey tests, distributions were visualized in polar space, and discrimination was evaluated via ROC/AUC analysis. Main results: CHSθ provided exceptional discrimination between pathological and healthy states (AUC = 0.866; 95% CI 0.859–0.873), while CHSmag showed physiological variation across cohorts. Arterial status was shifted toward higher CHSθ (approaching 90°) with aging, indicating progressive stiffening without proportional hemodynamic load increases. CHSθ was confirmed to be dominated by arterial compliance through sensitivity analysis, while CHSmag was found to reflect primarily SVR-CO balance. Rapid assessment of whether cardiovascular changes stem from arterial stiffening versus altered flow-resistance dynamics is enabled by this two-coordinate system. Significance: CHS provides a two-coordinate, physiologically grounded fingerprint that separates stiffness orientation from overall hemodynamic load. The index complements established stiffness measures and may support screening, triage, and longitudinal tracking, while enabling future bedside estimation from common biosignals.