Porcine and bovine aortic valve comparison for surgical optimization: A fluid-structure interaction modeling study.

BACKGROUND

Porcine aortic valve (PAV) and bovine aortic valve (BAV) are commonly used in aortic valve replacement (AVR) surgeries. A detailed comparison for their hemodynamic and structural stress/strain performances would help to better understand valve cardiac function and select valve type and size for AVR outcome optimizations.

METHODS

Eight fluid-structure interaction models were constructed to compare hemodynamic and stress/strain behaviors of PAV and BAV with 4 sizes (19, 21, 23, and 25 mm). Blood flow velocity, systolic cross-valve pressure gradient (SCVPG), geometric orifice area (GOA), flow shear stresses (FSS), and stress/strain were obtained for comparison.

RESULTS

Compared with PAV, BAV has better hemodynamic performance, with lower maximum flow velocity (7.17%) and pressure (9.82%), smaller pressure gradient (mean and peak SCVPG: 8.92% and 9.28%), larger GOA (9.56%) and lower FSS (6.61%). The averages of the mean and peak net pressure gradient values from 4 BAV models were 8.10% and 8.35% lower than that from PAV models. Larger valve sizes for both PAV and BAV had improved hemodynamic performance. Maximum flow velocity, pressure, mean SCVPG and maximum FSS from 25 mm BAV were 36.80%, 15.81%, 39.05% and 38.83% lower than those from 19 mm BAV. The GOA of PAV and BAV 25 mm Valve were 43.75% and 33.07% larger than 19 mm valves, respectively. BAV has lower stress on the leaflets than PAV.

CONCLUSIONS

BAV had better hemodynamic performance and lower leaflets stress than PAV. More patient studies are needed to validate our findings.