Elastic Properties of Aortic Wall in Patients With Bicuspid Aortic Valve by Magnetic Resonance Imaging

Abstract

Bicuspid aortic valve (BAV) is frequently associated with aortic wall abnormalities, including dilation of the ascending aorta and even dissection. We propose 2 new indexes of aortic wall biophysical properties, the maximum rates of systolic distension and diastolic recoil (MRSD and MRDR, respectively), in patients with BAV and matched control subjects. We evaluated 53 consecutive young patients with BAV (36 males, mean age 16 ± 4 years) with mild aortic valve disease and a control group of 22 age- and gender-matched healthy volunteers. All subjects underwent a cardiac magnetic resonance imaging study that included phase velocity mapping and cine acquisition at several aortic levels. The MRSD and MRDR were measured in the ascending aorta in both patients with BAV and controls. Of the 53 patients with BAV, 26 had enlarged ascending aortas (dilated BAV), and 27 had a normal aortic diameter (nondilated BAV). Compared to controls, the MRSD was significantly lower in the whole BAV group (4.37 ± 1.1 vs 9.1 ± 2.1), in patients with dilated BAV (4.5 ± 1.1 p <0.0001), and in those with nondilated BAV (4.3 ± 1.0, p <0.0001). The MRDR was greater in the whole BAV group (-4 ± 1.2 vs -7.6 ± 2.7, p <0.0001), in the dilated BAV group (-3.9 ± 1.3, p <0.0001), and in the nondilated BAV group (-4.1 ± 1.2, p <0.0001). A receiver operating characteristic curve analysis of MRSD distinguished BAV from controls with 100% sensitivity and 95% specificity. In conclusion, MRSD and MRDR were slower in the patients with BAV than in the controls, regardless of the dimensions of the ascending aorta.