Hemodynamic Performance and Blood Damage of the Intra-Aortic Pumps: A CFD-Based Investigation

TL;DR

This CFD-based study compares three intra-aortic blood pumps, introducing the Hemolytic Number as a new metric, and finds the impeller-driven pump superior in performance and hemocompatibility.

Contribution

The paper introduces the Hemolytic Number (HN) as a standardized metric for comparing pump hemolysis and demonstrates the superior performance of the impeller-driven pump.

Findings

Impeller pump achieved highest pressure head (~800 Pa at 4 L/min).

Impeller pump had the best hydraulic efficiency (~6% at 14 L/min).

Impeller pump showed lowest hemolysis (NIH = 0.0035 g/100L).

Abstract

Three intra-aortic blood pumps were evaluated and compared using CFD simulations. The aim of this study is to evaluate the hemodynamic performance and calculate the hemolytic potential of the pumps. The flow fields generated by the pumps were simulated using CFD with a wall-modeled large eddy simulation (WMLES) approach. The simulations produced pressure-flow curves, hydraulic efficiency, shear stress distributions, and hemolysis predictions. A grid study was conducted using the Grid Convergence Index (GCI) method, and a new dimensionless parameter, the Hemolytic Number (HN), was introduced as a standardized metric to compare hemolysis and universal pump performance. The impeller-driven pump had the highest-pressure head (~800 Pa at 4 L/min) and the best hydraulic efficiency (~6% at 14 L/min), outperforming both the single (maximum 2.7%) and triplet (maximum 2.2%) pumps. The NIH values were also lowest for the impeller pump (NIH = 0.0035 g/100L), indicating high hemocompatibility. Both the single and triplet pumps showed regions of recirculation, particularly at lower flow rates. A smaller HN indicates better hemocompatibility; for the impeller-driven pump, HN remains below 1 across the investigated flow rates. Overall, the impeller-driven pump outperformed the other designs in terms of both hemodynamic and hemolytic measurements. The findings provide valuable insights for the future development of intra-aortic pumps and the personalized selection of devices for individual patients.