Development of bronchial artery dilatation detected by MRI in adults with cystic fibrosis

Background Previous magnetic resonance imaging (MRI) studies demonstrated a high prevalence of bronchial artery dilatation (BAD) and its association with disease severity in people with cystic fibrosis (pwCF). More recently, dilated bronchial arteries (BA) were shown to decrease under modulator therapy. However, systematic imaging studies on the extent and development of BAD in pwCF are lacking. Methods 174 pwCF (mean age 27.8±7.9 years) undergoing standardised chest MRI including MR angiography (MRA) were included; 71 pwCF contributed ≥2 MRI. BAD prevalence and number of dilated BA were assessed visually, and disease severity using the chest MRI score. BA were segmented to measure mean lumen diameter (MLD) and mean lumen area (MLA). Percent predicted forced expiratory volume in 1 s (ppFEV1), hemoptysis, and throat swabs were recorded. Results At baseline, 93% of pwCF had ≥1 dilated BA, 41% had two, and 27% three (mean 2.1±1.0). MLD and MLA were 3.8±0.9 mm and 9.5±7.1 mm 2 , and correlated with ppFEV1 and MRI global, morphology, and perfusion scores (r=−0.22–0.34, p<0.001–0.021). In pwCF with chronic P. aeruginosa infection, the number of dilated BA was higher (2.3±0.8 versus 1.9±1.1, p=0.018). Hemoptysis occurred solely in pwCF with BAD (15%) and was associated with higher MLA (10.6±3.6 mm 2 versus 9.2±4.4 mm 2 , p=0.029) and a higher proportion of tortuous vessels (p=0.046). During follow-up, 16% developed a new dilated BA, associated with an increase in MRI global score (17.2±7.1 versus 20.5±6.6, p=0.001). Conclusions MRA sensitively detects BAD in pwCF. Higher disease severity is associated with BAD development, and larger size of dilated BA with hemoptysis.