Thousands of infants are born each year with abnormal physiology due to heart defects and structural disorders. The incidence of congenital heart defects is approximately 4–10 of every 10,000 live births. Those defects having the highest complexity, such as hypoplastic left heart syndrome and tricuspid atresia, lead to single ventricle physiology (SVP), requiring invasive heart surgery in the first year of life. Healthcare expenditures on the treatment of these disorders exceed $1.4 billion annually. Patients exhibiting SVP typically undergo three staged palliative cardiac surgeries that progressively offload the single ventricle while allowing time for growth, development, and adaptation to the altered physiology. The culminating Fontan procedure separates the pulmonary and systemic circulations and creates a total cavopulmonary connection (TCPC) where the inferior vena cava (IVC) and superior vena cava (SVC) are joined directly to feed the pulmonary arteries. In this configuration blood flows passively from the venous system into the lungs without a subpulmonary power source or right ventricle to provide a pressure boost to push blood to the left atrium. After the Fontan, elevated central venous pressures have been linked to mounting complications, such as liver disorders, cardiac arrhythmias, and thrombosis or clot formations. The main therapeutic alternative is a heart transplant, if patients survive the waiting period. Clinically approved blood pumps or ventricular assist devices (VADs) are not ideal treatment options since these have been designed for patients with normal anatomy, not for patients having dysfunctional or failing SVP.

As a new treatment strategy, Drexel’s biomedical engineers in collaboration with cardiac surgeons from the Children’s Hospital of Philadelphia have designed a collapsible, percutaneously-inserted, axial flow blood pump to support the cavopulmonary circulation of adolescent and adult Fontan patients. The design of this device takes into account biophysical factors such as hemolysis, biocompatibility, implantability, pump performance, biomaterials, and thrombosis. For Fontan patients, the target performance for this pump is to produce flow rates of 1–4 L/min with pressure rises of 2–25 mmHg for 1000–9000 RPM.

Impellers of varying designs have been produced and tested. Several impeller designs produced blood pressure rises of 4–26 mmHg for flow rates of 1–4 L/min for 6000–8000 RPM. A data regression analysis was completed and found the impeller with 400 °of blade twist to be the superior performer. A hydraulic test conducted on the prototype of the 400 ° impeller demonstrated pressure rises of 7–28 mmHg for flow rates of 1–4 L/min at 6000–8000 RPM.