Aim:
This case-control study is aimed at identifying radial vascular wall abnormalities in patients with fibromuscular dysplasia (FMD).
Methods:
High-frequency ultrasound scans of the radial arteries and of FMD patients and healthy controls were obtained by Vevo MD (70 MHz probe, FUJIFILM, VisualSonics, Toronto, Canada). Radial wall showed in all individuals two echogenic interfaces: the 1
st
( lumen-media) and the 2
nd
(media-adventitia). Intima-media (IMT), adventitia (AT), and global thickness (IMAT) were measured and wall cross-sectional area (WCSA) calculated. The disarray level of the two echogenic interfaces was assessed calculating the root mean square error (RMSE) between 20 gray-level profiles crossing the two interfaces and the profile obtained averaging them. For each echogenic interface, the RMSE was normalized for the maximum value of the corresponding mean profile (RMSE/mean).
Results:
11 treated hypertensive female FMD patients and 8 healthy control women (C) were enrolled (age 52±5 vs 45±13 years, p=0.51; BMI 26±3 vs 23±3, p=0.12; mean BP 97±7 vs 85±10, p=0.01). Radial internal diameter was similar (1.938±0.432 vs 1.701±0.532 mm, p=0.21). IMT (0.166±0.037 vs 0.128±0.022 mm, p=0.03), AT (0.114±0.029 vs 0.083±0.019 mm, p=0.008) and IMAT (0.281±0.042 vs 0.211±0.027 mm, p=0.003) were higher in FMD. Wall/lumen ratio was similar and WCSA increased in FMD, calculated with either IMT or IMAT. The maximum values of 1
st
(121±43 vs 157±22, p=0.09) and 2
nd
interface 109 ±44 vs133±18, p=0.09) tended to be lower, whereas RMSE/mean was higher in FMD (1
st
1.31±0.24 vs 0.83±0.32, p=0.006; 2
nd
1.37±0.38 vs 0.94±0.32, p=0.03). The difference was attenuated for the 1
st
but not for the 2
nd
interface when considering age and mean BP as covariates (p=0.054 and p=0.016 respectively).
Conclusions:
Wall ultrastructure of radial arteries of hypertensive FMD patients showed eutrophic remodeling. Furthermore, a peculiar “blurred” pattern occurred, characterized of loss of echogenicity and inhomogeneity of the two echogenic layers, independent of age and mean BP.
P1571Identification of radial vascular wall abnormalities by very-high frequency ultrasound in patients with spontaneous coronary artery dissection and fybromuscular dysplasia: the FUCHSIA study