Dynamic Arterial Elastance: Physiologic Basis, Current Clinical Evidence, and Future Directions.

Restoring arterial pressure in hypotensive shock is a primary resuscitation goal, yet increases in cardiac output after fluid administration do not consistently produce meaningful increases in arterial pressure. This dissociation highlights the importance of understanding pressure-flow interactions during hemodynamic interventions. Dynamic arterial elastance (EaDyn) is a functional hemodynamic index proposed to characterize these interactions. Rather than reflecting static vascular resistance, EaDyn is hypothesized to describe the dynamic relationship between cardiac output and arterial load within the framework of ventriculo-arterial coupling. Clinically, EaDyn has been investigated as a predictor of the arterial pressure response to fluid administration in preload-responsive patients and as a marker of pressure stability during vasopressor reduction. However, current clinical evidence remains limited, heterogeneous, and derived largely from selected populations. This review summarizes the physiologic basis of EaDyn, critically appraises the available clinical evidence, and highlights current limitations and priorities for future research.