Individuals with functionally normal bicuspid aortic valves exhibited significantly more high-grade helical flow patterns in the ascending aorta compared to those with tricuspid valves (85% vs 6%).
Observational (n=36)
Do flow patterns and wall shear stress in the ascending aorta differ between individuals with bicuspid aortic valves and tricuspid aortic valves?
Patients with functionally normal bicuspid aortic valves exhibit significantly altered flow patterns and higher wall shear stress in the ascending aorta compared to those with tricuspid valves, which may contribute to aortic dilation.
Absolute Event Rate: 85% vs 6%
AIMS: We compared flow and wall shear stress (WSS) patterns in the ascending aorta of individuals with either bicuspid aortic valve (BAV) or tricuspid aortic valve (TAV) using four-dimensional cardiovascular magnetic resonance (4D-CMR). BAV are known to be associated with dilation and dissection of the ascending aorta. However, the cause of vessel disease in patients with BAVs is unknown. Inborn connective tissue disease and also dilation secondary to increased WSS because of altered blood flow patterns in the ascending aorta are discussed as causes for dilation of the aorta. WSS can be estimated non-invasively by 4D-CMR. METHODS AND RESULTS: Eighteen, otherwise, healthy individuals with functionally normal BAVs were compared prospectively with an age- and sex-matched control group of healthy individuals with TAV. Blood flow data were obtained by 4D-CMR visualization and WSS was calculated with specific software tools. Eighty-five per cent of the individuals with BAVs showed a high-grade helical flow pattern in the ascending aorta compared with 6% of the individuals with TAV. WSS in the ascending aorta was significantly altered in individuals with BAVs compared with TAV. CONCLUSION: WSS and flow patterns in the ascending aorta in patients with BAVs without concomitant valve or vessel disease are significantly different compared with TAV. The significantly higher shear forces may have an impact on the development of aortic dilation in patients with BAVs.
Meierhofer et al. (2012) conducted an observational in Bicuspid aortic valve (n=36). Bicuspid aortic valve vs. Tricuspid aortic valve was evaluated on High-grade helical flow pattern in the ascending aorta. Individuals with functionally normal bicuspid aortic valves exhibited significantly more high-grade helical flow patterns in the ascending aorta compared to those with tricuspid valves (85% vs 6%).