Engineering New Treatments for Cardiovascular Disease Via Optimal Design and Physiologic Simulation

Alison L. Marsden, Ph.D. Postdoctoral Fellow
Stanford University
Stanford, CA Rigorous modeling and optimization of treatments for cardiovascular disease according to engineering principles provide a framework for testing new surgeries and interventions at no risk to patients. Ultimately these tools have the potential to complement doctors' clinical judgement and experience to improve outcomes for patients suffering from both congenital and acquired heart disease. In this talk I will discuss the application of computational fluid dynamics to the Fontan surgery, a treatment for severe congenital heart defects in which a patient is born with only one functioning ventricle. Patient specific geometric models were used to evaluate the performance of current Fontan surgical designs by quantifying fluid-mechanical efficiency under physiologic conditions including rest, graded exercise, and respiration (Marsden, et. al, Ann Biomed Eng, to appear). This work inspired a new "y-graft" design of the Fontan surgery. Evaluation of the new design demonstrates improved efficiency and lower Fontan pressures. Optimization is commonly used in engineering industry for design, but neither simulation or optimization are currently used to test surgical designs in advance of trying them on patients. Optimization of new surgical designs for patient specific models such as the Fontan surgery requires methods that are appropriate for expensive fluid mechanics problems with little or no gradient information. Efficient derivative-free surrogate-based optimization methods have been previously successful in reducing aerodynamic noise generated by airfoils in turbulent flow (Marsden, et. al J Fluid Mech, to appear). A similar set of tools is now being applied to fully couple optimization algorithms with time-dependent simulations of blood flow. I will present two model problems for optimization that are representative of important cardiovascular problems, a vessel bifurcation and an end-to-side anastomosis. Next, I will discuss the application of optimization tools in future work for the design of the Fontan surgery. Finally, I will describe the potential broad impact of optimization in designing devices and surgical procedures for congenital heart disease, coronary artery disease, and peripheral vascular disease.

Location: Grace Ford Salvatori Hall (GFS), Room 107

Audiences: Everyone Is Invited

Contact: April Mundy