Elastic Thinking: Open-Source Computational Dynamic Arterial Elastance as a Research Tool in Cardiac Surgery

PURPOSE The purpose of this new technology is to compute dynamic arterial elastance (Eadyn), E a d y n = p u l s e p r e s s u r e v a r i a t i o n strokevolumevariation which reflects ventricular–arterial coupling and is indicative of vasoplegia but remains underused in translational cardiac surgery research. DESCRIPTION We developed an open-source program that computes Eadyn from any arterial pressure waveform for cardiac surgery research. The framework includes: (1) heart rate detection; (2) systolic/diastolic assignment; (3) stroke-volume estimation using the Liljestrand–Zander model; (4) calibration of derived stroke volume with echocardiography; (5) respiratory-cycle identification; (6) computation of Eadyn. EVALUATION Feasibility was evaluated in a translational large animal model. The algorithm consistently detected physiologic heart rate, pressures, and respiratory rate. Average echo-calibrated stroke volume closely matched echocardiographic measurements. Post-bypass Eadyn decreased (pre-bypass median ∼0.86 vs post-bypass median ∼0.37), consistent with vasodilatory physiology and decoupling. CONCLUSIONS This program provides a feasible method to quantify Eadyn from arterial waveforms. The device-agnostic approach enables reproducible ventricular-arterial coupling assessment for cardiac surgery research and may have future clinical applications.