AUTHOR=Lee Jeesoo , Huh Hyungkyu , Scott Michael B. , Elbaz Mohammed S. M. , Puthumana Jyothy J. , McCarthy Patrick , Malaisrie S. Christopher , Markl Michael , Thomas James D. , Barker Alex J. 

TITLE=Valvular and ascending aortic hemodynamics of the On-X aortic valved conduit by same-day echocardiography and 4D flow MRI

JOURNAL=Frontiers in Cardiovascular Medicine

VOLUME=Volume 10 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2023.1256420

DOI=10.3389/fcvm.2023.1256420

ISSN=2297-055X

ABSTRACT=The purpose of this study is to assess whether the On-X aortic valved conduit better restores normal valvular and ascending aortic hemodynamics than other commonly used bileaflet mechanical valved conduit prostheses from St. Jude Medical and Carbomedics by using same-day transthoracic echocardiography (TTE) and 4D flow magnetic resonance imaging (MRI) examination. TTE and 4D flow MRI were acquired back-to-back in 10 patients with On-X, 6 patients with St. Jude (2) and Carbomedics (4) prostheses, and 36 healthy volunteers. TTE evaluated valvular hemodynamic parameters; transvalvular peak velocity (TPV), mean and peak transvalvular pressure gradient (TPG), and effective orifice area (EOA). 4D flow MRI evaluated peak systolic 3D viscous energy loss rate (VELR) density and mean vorticity magnitude in the ascending aorta. While higher TPV and mean and peak TPG were recorded in all patients compared to healthy subjects, the values in On-X patients were closer to those of healthy subjects (TPV 1.9±0.3 vs. 2.2±0.3 vs. 1.2±0.2 m/s, mean TPG 7.4±1.9 vs. 9.2±2.3 vs. 3.1±0.9 mmHg, peak TPG 15.3±5.2 vs. 18.9±5.2 vs. 6.1±1.8 mmHg, p<0.001). Likewise, while higher VELR density and mean vorticity magnitude were recorded in all patients compared to healthy subjects, the values in On-X patients were closer to those of healthy subjects (VELR: 50.6±20.1 vs. 89.8±35.2 vs. 21.4±9.2 W/m 3 , p<0.001) and vorticity (147.6±30.0 vs. 191.2±26.0 vs. 84.6±20.5 s-1, p<0.001). This study demonstrates that the On-X aortic valved conduit may produce less aberrant hemodynamics in the AAo while maintaining similar valvular hemodynamics compared to St. Jude Medical and Carbomedics alternatives.