Repaired coarctation of the aorta, persistent arterial hypertension and the selfish brain

Jonathan C L Rodrigues,Konstantina Mitrousi,Julian F R Paton,Angus K Nightingale,Stephen M Lyen,Mark C K Hamilton,Emma C Hart,Nathan E Manghat,Stephanie L Curtis,Matthew F R Jaring,Melissa C Werndle

doi:10.1186/s12968-019-0578-8

Abstract

BackgroundIt has been estimated that 20–30% of repaired aortic coarctation (CoA) patients develop hypertension, with significant cardiovascular morbidity and mortality. Vertebral artery hypoplasia (VAH) with an incomplete posterior circle of Willis (ipCoW; VAH + ipCoW) is associated with increased cerebrovascular resistance before the onset of increased sympathetic nerve activity in borderline hypertensive humans, suggesting brainstem hypoperfusion may evoke hypertension to maintain cerebral blood flow: the “selfish brain” hypothesis. We now assess the “selfish brain” in hypertension post-CoA repair.MethodsTime-of-flight cardiovascular magnetic resonance angiography from 127 repaired CoA patients (34 ± 14 years, 61% male, systolic blood pressure (SBP) 138 ± 19 mmHg, diastolic blood pressure (DBP) 76 ± 11 mmHg) was compared with 33 normotensive controls (42 ± 14 years, 48% male, SBP 124 ± 10 mmHg, DBP 76 ± 8 mmHg). VAH was defined as < 2 mm and ipCoW as hypoplasia of one or both posterior communicating arteries.ResultsVAH + ipCoW was more prevalent in repaired CoA than controls (odds ratio: 5.8 [1.6–20.8], p = 0.007), after controlling for age, sex and body mass index (BMI). VAH + ipCoW was an independent predictor of hypertension (odds ratio: 2.5 [1.2–5.2], p = 0.017), after controlling for age, gender and BMI. Repaired CoA subjects with VAH + ipCoW were more likely to have difficult to treat hypertension (odds ratio: 3.3 [1.01–10.7], p = 0.049). Neither age at time of CoA repair nor any specific repair type were significant predictors of VAH + ipCoW in univariate regression analysis.ConclusionsVAH + ipCoW predicts arterial hypertension and difficult to treat hypertension in repaired CoA. It is unrelated to age at time of repair or repair type. CoA appears to be a marker of wider congenital cerebrovascular problems. Understanding the “selfish brain” in post-CoA repair may help guide management.Journal subject codesHigh Blood Pressure; Hypertension; Magnetic Resonance Imaging (MRI); Cardiovascular Surgery; Cerebrovascular Malformations.

Highlights

It has been estimated that 20–30% of repaired aortic coarctation (CoA) patients develop hypertension, with significant cardiovascular morbidity and mortality
We investigate the role of the “selfish brain” in hypertension following CoA repair
There were no significant differences between post-repaired CoA subjects and controls in sex or body mass index (BMI) (25 ± 5 vs 24 ± 3 kg/m2, p = 0.23)

Summary

Introduction

It has been estimated that 20–30% of repaired aortic coarctation (CoA) patients develop hypertension, with significant cardiovascular morbidity and mortality. We assess the “selfish brain” in hypertension post-CoA repair. CoA is associated with increased risk of multiple cardiovascular complications including coronary artery disease, aortic aneurysm formation and cerebrovascular disease [3,4,5]. Arterial hypertension occurs in approximately 30% following CoA repair [6, 7] and is a unifying risk factor. Age at the time of the original CoA repair has been shown to contribute to subsequent risk of hypertension [11]. A high prevalence of hypertension has been subsequently demonstrated in children aged 7–16 years who were treated for CoA at a median age of 0.2 years and without residual significant arch obstruction [7]. The reason why hypertension is so common in repaired CoA remains enigmatic

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