Enhancing the implantation of mechanical circulatory support devices using computational simulations

Area of Science:

• Biomedical Engineering
• Cardiovascular Research
• Computational Fluid Dynamics

Background:

• End-stage heart failure often requires mechanical circulatory support with left ventricular assist devices (LVADs).
• LVAD implantation carries risks, including aortic regurgitation and thrombus formation.
• Optimizing surgical technique may mitigate these complications.

Purpose of the Study:

• To assess if optimizing LVAD outflow graft (OG) implantation technique can minimize the risk of aortic complications.
• To evaluate the impact of different geometrical parameters of OG anastomosis on aortic flow patterns.

Main Methods:

• Computational fluid dynamics (CFD) was used to simulate aortic flow patterns.
• A 3D aortic model was created, varying OG distance from the ventriculo-arterial junction, cardinal position, and angle.
• LVAD continuous flow and native cardiac cycle were used as inlet boundaries.

Main Results:

• Specific OG positioning significantly impacts hemodynamic parameters like wall shear stress (WSS).
• Attaching the OG to the coronal side at a 45° ± 10° angle, 55 mm from the AVJ, reduced aortic root WSS by approximately 50%.
• CFD analysis quantified the influence of OG placement on velocity, pressure, vorticity, and turbulent kinetic energy.

Conclusions:

• Outflow graft placement is a critical factor influencing hemodynamic patterns in LVAD patients.
• CFD modeling offers a valuable tool for optimizing OG positioning to reduce cardiovascular complications post-LVAD implantation.
• This approach holds potential for improving long-term outcomes in patients with mechanical circulatory support.