Key result
Mechanical aortic valve replacement does not increase peak wall shear stress in the ascending aorta compared to healthy controls (1.04 vs 1.33 Pa, p=0.123).
Why the study?
Progressive ascending aortic dilatation occurs after mAVR, possibly due to altered blood flow and wall shear stress patterns induced by bileaflet mechanical valve designs.
Does mechanical aortic valve replacement alter ascending aortic wall shear stress compared to healthy controls and bicuspid aortic valve patients?
Cross-Sectional (n=35)
No
Does mechanical aortic valve replacement alter ascending aortic wall shear stress compared to healthy controls and bicuspid aortic valve patients?
Absolute Event Rate: 1.04% vs 1.33%
p-value: p=0.123
Bileaflet mechanical aortic valves do not increase ascending aortic wall shear stress compared to healthy controls, suggesting no hemodynamic indication for intensified follow-up of the ascending aorta after mAVR.
Findings should not alter valve selection; leaves open need for longitudinal studies on post-MAVR aortic remodeling.
Progressive ascending aortic dilatation has been observed after mechanical aortic valve replacement (mAVR), possibly due to altered blood flow and wall shear stress (WSS) patterns induced by their bileaflet design. We examined the effect of mAVR on WSS in the ascending aorta using time-resolved 4D flow MRI. Fifteen patients with mechanical aortic valve prostheses, 10 patients with bicuspid aortic valve disease and 10 healthy individuals underwent thoracic 4D flow MRI. Peak systolic hemodynamic parameters (velocity and WSS) and vessel diameters were assessed in the ascending aorta. In addition, three-dimensional per-voxel analysis was used to compare velocity and WSS between patient groups and healthy controls. Peak aortic diameters were significantly higher in mAVR and BAV patients compared to healthy controls (p = 0.011). Mean aortic diameters were comparable between mAVR and BAV patients. No differences in 4D flow MRI-derived mean blood flow velocity and peak WSS were found between the three groups. Compared to healthy controls, mean WSS was significantly lower in mAVR patients (p = 0.031). Per-voxel analysis revealed no increased WSS in the ascending aortic wall and significantly lower velocity and WSS values in mAVR patients compared to healthy controls. In contrast, regions of significantly increased outer lumen velocities and WSS in BAV patients compared to healthy controls were found. This study shows that there is no increased ascending aortic WSS after mAVR. Our results suggest that, in contrast to BAV patients, there is no indication for intensified follow-up of the ascending aorta after mAVR.
No takes yet. Share an insight, caveat, or question.
Farag et al. (2019) conducted a cross-sectional in Mechanical aortic valve replacement (n=35). Mechanical aortic valve replacement vs. Healthy controls and bicuspid aortic valve patients was evaluated on Peak wall shear stress (WSS) in the ascending aorta (p=0.123). Mechanical aortic valve replacement does not increase peak wall shear stress in the ascending aorta compared to healthy controls (1.04 vs 1.33 Pa, p=0.123).
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: