Investigating Aortic Root Hemodynamics With EVAHEART2 Pump Speed Modulation.

Area of Science:

• Cardiovascular Engineering
• Biomedical Engineering
• Hemodynamics

Background:

• Left ventricular assist device (LVAD) therapy is crucial for heart failure but can impede aortic valve opening (AVO).
• Reduced AVO increases risks of blood stagnation and thrombus formation in the aortic root.
• EVAHEART2 (EVA2) pump speed modulation (PSM) offers a potential strategy to promote AVO.

Purpose of the Study:

• To investigate the impact of PSM on aortic root hemodynamics.
• To quantify the transaortic valve flow necessary for effective aortic root washout.
• To evaluate how PSM influences LVAD flow pulsatility.

Main Methods:

• Computational fluid dynamics (CFD) simulations were employed.
• Quantified aortic root washout and washout progression.
• Utilized platelet tracking to assess thrombogenic potential.

Main Results:

• A closed aortic valve resulted in only 60% blood washout in 4 seconds.
• Aortic valve opening (AVO) improved washout efficiency to over 80% within 3 seconds.
• Platelet stagnation risk decreased by up to 60% with transaortic flow compared to a nonfunctional AV.
• Higher transaortic flow correlated with the lowest thrombogenic potential score.

Conclusions:

• Transaortic valve flow is the key determinant of aortic root washout.
• Utilizing EVA2 PSM to increase transaortic flow can enhance aortic root washout.
• Strategies promoting a functional aortic valve are vital for LVAD patients.