Persistent Aortic Arch Hypoplasia After Coarctation Treatment Is Associated With Late Systemic Hypertension

Abstract

Background: Mild transverse aortic arch (TAA) hypoplasia is common after coarctation treatment, but is considered benign in the absence of an arm-leg systolic blood pressure (SBP) difference. Hypertension (HTN) is a common long-term morbidity after successful coarctation treatment. We examined whether mild TAA hypoplasia after coarctation treatment is associated with late systemic HTN.

Methods and results: We retrospectively reviewed 92 patients (median age, 19.9 years; range, 4.9 to 57.8; 60% male) 14.1±10.3 years after successful coarctation treatment (surgery in 63, stent in 16, and balloon dilation in 13), excluding those with resting right arm-leg blood pressure gradient >20 mm Hg, atypical coarctation, and major associated heart defects. Minimum body-surface area (BSA)-adjusted TAA cross-sectional area (CSA) was calculated from cardiac magnetic resonance (CMR) images. On follow-up, 38 of 92 (41%) patients had systemic HTN using standard criteria. Systemic HTN was independently associated with smaller TAA CSA/BSA (P=0.006; odds ratio [OR], 6.41 per 0.5 cm(2)/m(2) decrease), higher age at CMR (P=0.03; OR, 1.57 per 5-year increase), and in a subset (n=61), higher arm-leg SBP difference during exercise (P=0.05; OR, 1.03 per 1-mm-Hg increase). Lower ratio of TAA diameter/descending aorta diameter was associated with a larger increase in right arm SBP during peak exercise (P=0.006; r(2)=0.11).

Conclusions: Persistent mild aortic arch hypoplasia, even in the absence of an arm-leg SBP difference at rest, is associated with late systemic HTN. Further studies should be undertaken to determine whether more-aggressive arch reconstruction at initial repair can reduce the incidence of systemic HTN.

Keywords: cardiac MRI; coarctation; hypertension; transverse aortic arch.

© 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Figures

Figure 1

A, Maximum intensity projection from the gadolinium 3-dimensional (3D) MRA showing the sites of measurements. The transverse aortic arch (1) extending from the origin of the RIA to the origin of the LSCA was measured at its narrowest segment. The isthmus (2) was measured just distal to the origin of the LSCA. The thoracic descending aorta (3) was measured at the level of the left atrium. B and C, Example of multiplanar reformatting of the 3D MRA to measure 2 orthogonal diameters and cross-sectional area of the transverse aortic arch. LCCA indicates left common carotid artery; LSCA, left subclavian artery; MRA, magnetic resonance angiogram; RIA, right innominate artery.

Figure 2

Prevalence of systemic hypertension in tertiles of TAA CSA indexed to BSA. Systemic hypertension was more prevalent in patients who were in the lower tertiles of TAA CSA/BSA. BSA indicates body-surface area; CSA, cross-sectional area; TAA, transverse aortic arch.

Figure 3

Factors associated with blood pressure response to exercise. Greater increase in right arm SBP was associated with lower TAA/DAO diameter ratio (A) and greater arm-leg SBP difference at peak exercise (B). DAO indicates descending aorta; SBP, systolic blood pressure; TAA, transverse aortic arch.

Figure 4

Factors associated with LV mass. Higher BSA-adjusted LV mass was associated with larger increase in right arm SBP with stress (A) and with male gender (B). BSA indicates body-surface area; LV, left ventricular; SBP, systolic blood pressure.