Quantification of Aortic Valve Regurgitation by Phase-Contrast Magnetic Resonance in Patients with Bicuspid Aortic Valve: Where to Measure the Flow?

Results The correlation between the LVSV and the forward flow in the LVOT, the AV and the AAo was good in both BAV patients (r= 0.97/0.96/0.86; p < 0.01 for all) and controls (r= 0.96/0.93/0.87; p < 0.01 for all). However, in relation with the LVSV, the forward flow in the AAo was mildly underestimated in controls and much more in BAV patients [median (interquartile range): 9% (-1%/16%) vs. 17% (7%/27%); p = 0.05]. This was not the case in the LVOT [5% (0%/8%) vs. 5% (-3%/11%); p = 0.94] and the AV [0% (-5%/8%) vs. 1% (-4%/6%); p = 0.77], where the differences were mild and did not differ between groups (figure 1). By applying cut-off values of regurgitant fraction in the AAo, the severity of the AR was overestimated in 6 out of 16 BAV patients (38%) with AR, as compared with the flow quantification in the LVOT or the AV. In the AAo the relative mean SI was lower in the BAV patients compared to controls [1.34 +/- 0.15 vs. 1.58 +/- 0.26; p < 0.01], suggesting more intravoxel dephasing in BAV patients.