A research project supported by the National Institutes of Health is seeking to create a cavopulmonary assist device (CPAD) to support patients with single-ventricle heart defects and potentially lead to improved quality and longevity of life.
Dr. Alan Palazzolo, James J. Cain I Professor in the J. Mike Walker '66 Department of Mechanical Engineering at Texas A&M University, is working with principal investigator Dr. Mark Rodefeld, a thoracic surgeon at Indiana University. Alongside Palazzolo, Texas A&M mechanical engineering doctoral candidates Shreyas Sarfare and MD Shujan Ali are participating in the project.
Those born with a single ventricle heart defect have just one of their two pumping chambers, known as ventricles, that is large or strong enough to properly function — leading to an over-working of the heart.
The goal of the research is to specifically assist the patients who undergo Fontan reconstruction surgery, a procedure that seeks to aid with single ventricle defects of the heart. The Fontan procedure is most commonly performed on infants and children.
"Survivors of the single-ventricle Fontan procedure have lifelong chronic circulatory inefficiency," Palazzolo said. "Therapies to prevent or reverse this circulatory decline remain extremely limited. The proposed ventricular assist device would shift the univentricular circulation toward more stable biventricular equivalency.”
The research team's approach is to design the internal flow path for the heart in a manner that inhibits thrombosis and hemolysis, and to mitigate CPAD-induced vibration experienced by patients. Palazzolo said the greatest challenges facing their research include determining a way to minimize the risk of blood clots (thrombus), hemolysis (the rupture or destruction of red blood cells) and power consumption of the device's motor.
"We are utilizing computational fluid dynamics to design a hydraulically efficient motor/pump matched with the hydraulics of the overall body’s circulatory system, with low propensity for thrombus formation and hemolysis in the high-speed rotating motor/pump, low vibrations and low hot spot temperature in the internal drive motor," Palazzolo said.
As the project continues, Palazzolo said a long-term objective of the project will be to use computational fluid dynamics to model the formation of thrombus more accurately.