A Discrete Hemodynamic Control System: Proof-of-Concept In-Vivo Study in Canine Heart Failure Using a Pulmonary Artery Catheter.

Objective: Managing heart failure requires simultaneous regulation of mean arterial pressure, cardiac output, and left atrial pressure, which is challenging due to complex cardiovascular interactions and limited monitoring. This study presents a proof-of-concept in-vivo evaluation of a discrete two-degree-of-freedom hemodynamic control system designed to regulate these three hemodynamic variables through titration of cardiovascular interventions under pulmonary artery catheter monitoring. Results: Across five consecutive trials in three canine models of heart failure induced by tachycardia pacing, the cohort-averaged mean arterial pressure, cardiac output, and left atrial pressure were each within ±10% of their respective targets when evaluated using the final three intervention measurements, with absolute percentage errors decreasing from 16.8% to 9.0%, 23.4% to 3.8%, and 87.5% to 5.5%, respectively. In a more severely complicated heart failure model with coronary embolization, outcomes revealed control limitation primarily due to pharmacological resistance, highlighting the importance of choosing the appropriate target value. Conclusions: This proof-of-concept in-vivo study demonstrates the feasibility of implementing discrete two-degree-of-freedom hemodynamic control under pulmonary artery catheter-based monitoring and phlebotomy-mediated volume removal in anesthetized canine models of tachycardia-pacing-induced heart failure. Further studies are required to evaluate the effects of inter-subject variability and clinical generalizability.