Aorta size mismatch predicts decreased exercise capacity in patients with successfully repaired coarctation of the aorta
Mandell JG, Loke YH, Mass PN, Opfermann J, Cleveland V, Aslan S, Hibino N, Krieger A, Olivieri LJ. Aorta size mismatch predicts decreased exercise capacity in patients with successfully repaired coarctation of the aorta. J Thorac Cardiovasc Surg. 2020 Oct 7:S0022-5223(20)32707-0. doi: 10.1016/j.jtcvs.2020.09.103. Epub ahead of print. PMID: 33131888
OBJECTIVE: Coarctation of the aorta (CoA) is associated with decreased exercise capacity despite successful repair with no residual stenosis; however, the hemodynamic mechanism remains unknown. This study aims to correlate aortic arch geometry with exercise capacity in patients with successfully repaired CoA and explain hemodynamic changes using 3-dimensional-printed aorta models in a mock circulatory flow loop.
METHODS: A retrospective chart review identified patients with CoA repair who had cardiac magnetic resonance imaging and an exercise stress test. Measurements included aorta diameters, arch height to diameter ratio, left ventricular function, and percent descending aorta (%DAo) flow. Each aorta was printed 3-dimensionally for the flow loop. Flow and pressure were measured at the ascending aorta (AAo) and DAo during simulated rest and exercise. Measurements were correlated with percent predicted peak oxygen consumption (VO2)
RESULTS: Fifteen patients (mean age 26.8 ± 8.6 years) had a VO2
CONCLUSIONS: This study suggests aorta size mismatch (DAAo/DDAo) is a novel, clinically important measurement predicting exercise capacity in patients with successful CoA repair, likely due to increased resistance and altered flow distribution. Aorta size mismatch and %DAo flow are targets for further clinical evaluation in repaired CoA.