Aortic arch shape is not associated with hypertensive response to exercise in patients with repaired congenital heart diseases.
BACKGROUND
Aortic arch geometry is linked to abnormal blood pressure (BP) response to maximum exercise. This study aims to quantitatively assess whether aortic arch geometry plays a role in blood pressure (BP) response to exercise.


METHODS
60 age- and BSA-matched subjects--20 post-aortic coarctation (CoA) repair, 20 transposition of great arteries post arterial switch operation (ASO) and 20 healthy controls--had a three-dimensional (3D), whole heart magnetic resonance angiography (MRA) at 1.5 Tesla, 3D geometric reconstructions created from the MRA. All subjects underwent cardiopulmonary exercise test on the same day as MRA using an ergometer cycle with manual BP measurements. Geometric analysis and their correlation with BP at peak exercise were assessed.


RESULTS
Arch curvature was similarly acute in both the post-CoA and ASO cases [0.05 ± 0.01 vs. 0.05 ± 0.01 (1/mm/m²); p = 1.0] and significantly different to that of normal healthy controls [0.05 ± 0.01 vs. 0.03 ± 0.01 (1/mm/m²), p < 0.001]. Indexed transverse arch cross sectional area were significantly abnormal in the post-CoA cases compared to the ASO cases (117.8 ± 47.7 vs. 221.3 ± 44.6; p < 0.001) and controls (117.8 ± 47.7 vs. 157.5 ± 27.2 mm²; p = 0.003). BP response to peak exercise did not correlate with arch curvature (r = 0.203, p = 0.120), but showed inverse correlation with indexed minimum cross sectional area of transverse arch and isthmus (r = -0.364, p = 0.004), and ratios of minimum arch area/ descending diameter (r = -0.491, p < 0.001).


CONCLUSIONS
Transverse arch and isthmus hypoplasia, rather than acute arch angulation plays a role in the pathophysiology of BP response to peak exercise following CoA repair.
Hopewell N
HN
Ntsinjana
Giovanni
G
Biglino
Claudio
C
Capelli
Oliver
O
Tann
Alessandro
A
Giardini
Graham
G
Derrick
Silvia
S
Schievano
Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science & Cardiorespiratory Unit, Great Ormond Street Hospital for Children, NHS Trust, London, UK. a.taylor76@ucl.ac.uk.
Andrew M
AM
Taylor
D000293:Adolescent; D001013:Aorta, Thoracic / Q000002:abnormalities / Q000503:physiopathology / Q000601:surgery*; D001017:Aortic Coarctation / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D001794:Blood Pressure; D001830:Body Surface Area; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D016022:Case-Control Studies; D002648:Child; D015444:Exercise; D005080:Exercise Test; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D018810:Magnetic Resonance Angiography; D008297:Male; D011237:Predictive Value of Tests; D014188:Transposition of Great Vessels / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D055815:Young Adult