Optimizing cerebral perfusion and hemodynamics during cardiopulmonary bypass through cannula design combining in...

Area of Science:

• Biomedical Engineering
• Cardiovascular Surgery
• Medical Device Design

Background:

• Cardiopulmonary bypass (CPB) is essential for cardiac surgery but carries risks of neurological complications like stroke due to embolisms and reduced cerebral blood flow.
• Current aortic cannulas may contribute to these complications by causing suboptimal aortic root washout and high wall shear stress.

Purpose of the Study:

• To develop and evaluate novel aortic cannula designs aimed at mitigating neurological risks associated with CPB.
• To enhance cerebral perfusion and reduce embolic events during cardiopulmonary bypass procedures.

Main Methods:

• Design and in vivo testing of an optiCAN prototype with helical outflow and jet-splitting dispersion.
• In vitro assessment of pressure loss and hemolysis.
• In silico computational fluid dynamics (CFD) simulations of cannula performance in a human aortic model.
• Development of a second-generation design (opti²CAN) based on CFD findings.

Main Results:

• The optiCAN prototype restored cerebral perfusion to 97.5% of physiological flow in vivo, compared to 74.6% for a commercial cannula.
• optiCAN demonstrated unaffected pressure loss and hemolysis in vitro.
• CFD simulations confirmed improved aortic root washout with optiCAN, reducing thromboembolism risk.
• CFD identified high wall shear stress regions linked to plaque rupture risk, informing the opti²CAN design.

Conclusions:

• Novel aortic cannula designs, optiCAN and opti²CAN, show significant potential to reduce neurological complications and stroke prevalence after CPB.
• These designs offer improved cerebral perfusion, better aortic root washout, and optimized hemodynamics, particularly beneficial for high-risk patients.
• The study highlights the value of integrated in vivo, in vitro, and in silico methods for medical device innovation in cardiovascular surgery.