GALCIT Colloquium

Cardiovascular disease continues to be the leading cause of death worldwide.  Each year there are more than one million heart surgeries and procedures conducted in the US alone; about one quarter of all open heart surgeries are performed to remedy heart valve malfunctions. Prosthetic heart valves have been implanted for more than 50 years and, nowadays, such devices are readily available in a wide variety of designs. However, the performance of these prostheses is still far from ideal, as patients have to endure numerous post-operatory complications. Surprisingly, or maybe not, many of the performance problems are related to the fluid flow through such devices. In this talk, an overview of the current state of prosthetic heart valve research will be given. I will present our efforts to find a simplified flow configuration that permits us to make progress in the fundamental understanding of the problem but yet retains the complexities needed for it to be relevant for real heart valves. A pulsatile channel flow interacting with a pair of flexible elastic leaflets is considered. The size-elasticity-flow conditions for which the array functions as a valve are found and analyzed. To complete our study, we also address the need to minimize the amount of stress imposed to the fluid in a given valve design. Finally, some preliminary results of the effect of considering non Newtonian fluids will be presented and discussed.