Assessment of haemolysis models for a positive-displacement total artificial heart.

The assessment and reduction of haemolysis within mechanical circulatory support (MCS) remains a concern with regard to device safety and regulatory approval. Numerical methods for predicting haemolysis have typically been applied to rotary MCS devices and the extent to which these methods apply to positive-displacement MCS is unclear. The aim of this study was to evaluate the suitability of these methods for assessing haemolysis in positive-displacement blood pumps.

Fluid-structure interaction modelling of a positive-displacement Total Artificial Heart.

For those suffering from end-stage biventricular heart failure, and where a heart transplantation is not a viable option, a Total Artificial Heart (TAH) can be used as a bridge to transplant device. The Realheart TAH is a four-chamber artificial heart that uses a positive-displacement pumping technique mimicking the native heart to produce pulsatile flow governed by a pair of bileaflet mechanical heart valves. The aim of this work was to create a method for simulating haemodynamics in positive-displacement blood pumps, using computational fluid dynamics with fluid-structure interaction to eliminate the need for pre-existing in vitro valve motion data, and then use it to investigate the performance of the Realheart TAH across a range of operating conditions.

In vitro hemolytic performance of the Realheart® V11C TAH prototype with porcine blood.

Background: Hemolysis testing of new devices to treat heart failure is a regulatory requirement. The ASTM F1841-97 standard for hemolysis testing was developed for continuous flow pumps and does not specify test rig design. When research groups use different methodologies, results are difficult to compare.

Hemodynamic characterization of the Realheart® total artificial heart with a hybrid cardiovascular simulator.

Background: Heart failure is a growing health problem worldwide. Due to the lack of donor hearts there is a need for alternative therapies, such as total artificial hearts (TAHs). The aim of this study is to evaluate the hemodynamic performance of the Realheart® TAH, a new 4-chamber cardiac prosthesis device.

Video-based valve motion combined with computational fluid dynamics gives stable and accurate simulations of blood flow in the Realheart total artificial heart.

Background: Patients with end-stage, biventricular heart failure, and for whom heart transplantation is not an option, may be given a Total Artificial Heart (TAH). The Realheart® is a novel TAH which pumps blood by mimicking the native heart with translation of an atrioventricular plane. The aim of this work was to create a strategy for using Computational Fluid Dynamics (CFD) to simulate haemodynamics in the Realheart®, including motion of the atrioventricular plane and valves.

Preclinical Device Thrombogenicity Assessments: Key Messages From the 2018 FDA, Industry, and Academia Forum.

Device-related thrombosis and thromboembolic complications remain a major clinical concern and often impact patient morbidity and mortality. Thus, improved preclinical thrombogenicity assessment methods that better predict clinical outcomes and enhance patient safety are needed. However, there are several challenges and limitations associated with developing and performing preclinical thrombogenicity assessments on the bench and in animals (e.

Hemodilution Increases the Susceptibility of Red Blood Cells to Mechanical Shear Stress During In Vitro Hemolysis Testing.

The American Society for Testing and Materials (ASTM) F1841 standard for the assessment of hemolysis in blood pumps recommends using phosphate-buffered saline (PBS) for hemodilution to standardize hematocrit (HCT). However, PBS increases red blood cell mechanical fragility and hemolysis. Herein, we investigated diluents and dilutions during in vitro testing to reduce hemodilution bias when assessing hemolysis.