24 Clinical utility of repeat cardiovascular magnetic resonance imaging in patients with repaired coarctation of the aorta

Introduction Coarctation of the aorta (CoA) is a congenital narrowing of the aorta which often requires repair. As post-operative complications include recurrent coarctation, aneurysm or pseudoaneurysm formation and aortic rupture, lifelong surveillance with cardiovascular magnetic resonance (CMR) or computed tomography (CT) is currently recommended. However, the ideal imaging interval for these patients is currently unclear, with limited data regarding the natural progression in aortic size in this patient cohort. We aimed to assess the change in aortic dimensions over time in adult patients with repaired coarctation, and to determine the optimum interval for ongoing surveillance. Materials and Methods Consecutive patients (18 years or older) who had at least two CMRs performed (at least one year apart) for repaired CoA were enrolled from 2009 – 2022. Aortic dimensions were measured at three sites: aortic sinuses, ascending aorta (at level of pulmonary artery bifurcation) and the site of coarctation. A change of ≤2mm was considered within measurement error. The annualised change in aortic diameter was calculated through comparison of aortic dimensions from the earliest and latest CMR scan. Results 65 patients (36 male 29 female) were eligible for inclusion. 43 (66%) had a bicuspid aortic valve (BAV). Median time between scan was 5 years (range 15 months to 13 years). There was a mean absolute change of 1.0mm at the sinuses, 1.0mm at the ascending aorta, and 1.0mm at the site of coarctation (table 1). Annualised growth was 0.2mm/year at the sinuses, 0.3mm/year at the ascending aorta, and 0.1mm/year at the site of coarctation. No patients had re-coarctation of the aorta. Growth of >3mm over 5 years was seen in 12% (aortic sinuses) and 18% (ascending aorta). Discussion Our data demonstrate that most patients with repaired CoA have stable aortic dimensions on serial imaging. Only a small minority of patients show a significant increase in their aortic dimensions. Conclusion The majority of patients with repaired CoA of the aorta require imaging surveillance no more frequently than every five years. Acknowledgements KET acknowledges support from the British Heart Foundation Clinical Research Training Fellowship (FS/CRT/21/24268).