Usefulness of assessing the descending aorta flow pattern for predicting the need for intervention in patients with aortic coarctation

Background: Nowadays, evaluation of the need for intervention in patients with aortic coarctation (AC) is based on anatomical and clinical data. The purpose of the study was to analyze the utility of assessing flow in the thoracic descending aorta using magnetic resonance imaging (MRI) in patients with AC. Methods: Patients with a diagnosis or suspicion of AC, who underwent MRI study between 2008-2016 in a single tertiary center, were retrospectively studied. MRI standardized protocol included gadolinium enhanced angiographic 3-D sequences to evaluate relative stenosis (RS) and phase contrast imaging to assess flow in the descending aorta. Results: 106 patients {70 men (66%), mean age 22 ± 17 years} were included. Of these, 28 (26%) required surgical intervention during the first year after evaluation and 9 (9.3%) required percutaneous treatment. AUROC curves were applied to find best cut-off points of imaging variables. Imaging variables were entered into a multivariate logistic regression model including the presence of arterial hypertension. Percentage of flow increase was shown to be an independent predictor of the need for an intervention (OR, 7.2; 95%CI, 1-20; p=0.03) and adding this parameter in the standard work-up represented a significant increase in diagnostic accuracy (S, 85%; Sp, 89%; vs. S, 62%; Sp, 92%). Conclusion: physiological assessment of flow pattern in descending aorta by MRI significantly increases the ability to evaluate the need for invasive treatment in AC patients beyond standard clinical and anatomical study.