title: Arterial mechanics at rest and during exercise in adolescents and young adults after arterial switch operation for complete transposition of the great arteries.
abstract: We sought to determine the arterial mechanics at rest and during exercise in adolescents and young adults with complete transposition of the great arteries after arterial switch operation and their relations with neoaortic complications. Thirty patients (22 men) aged 16.2 ± 2.1 years and 22 controls (15 men) were studied. Central and peripheral arterial pulse wave velocities, carotid and radial augmentation indices, and central systolic blood pressure (cSBP) were determined by oscillometry and applanation tonometry, whereas arterial dimensions were measured by 2-dimensional echocardiography. Arterial strain, distensibility, and stiffness were determined at rest and during supine bicycle exercise testing. At rest, patients had significantly higher heart-carotid pulse wave velocity, carotid and radial augmentation indices, and cSBP than controls. At rest and during submaximal exercise, patients had significantly lower aortic strain and distensibility, greater aortic and carotid stiffness, and higher SBP than controls. Dilated aortic sinus found in 23 (76.7%) patients was associated with lower aortic distensibility, greater aortic stiffness, and higher cSBP at rest and lower aortic distensibility and strain at submaximal exercise. Significant aortic regurgitation found in 20% (6 of 30) of patients was associated with significantly higher neoaortic z scores. Multivariate analysis identified aortic stiffness at rest (β = 0.46, p = 0.003) and age at operation (β = 0.44, p = 0.004) as significant determinants of aortic sinus z scores. In conclusion, altered mechanics of the central arteries are present at rest and during exercise in adolescents and young adults after arterial switch operation. These findings may have important implications on progression of neoaortic root dilation, exercise recommendations, and medical therapy.
authors.affiliation: Department of Pediatrics and Adolescent Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China.
authors.forename: Robin H
authors.initials: RH
authors.lastname: Chen
authors.affiliation: Department of Pediatrics and Adolescent Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China.
authors.forename: Sophia J
authors.initials: SJ
authors.lastname: Wong
authors.affiliation: Department of Pediatrics and Adolescent Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China.
authors.forename: Wilfred H
authors.initials: WH
authors.lastname: Wong
authors.affiliation: Department of Pediatrics and Adolescent Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China. Electronic address: xfcheung@hku.hk.
authors.forename: Yiu-Fai
authors.initials: YF
authors.lastname: Cheung
mesh_terms: D000293:Adolescent; D001011:Aorta / Q000000981:diagnostic imaging / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology; D004452:Echocardiography; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry; D009991:Oscillometry; D011651:Pulmonary Artery / Q000000981:diagnostic imaging / Q000502:physiology*; D063177:Pulse Wave Analysis; D012146:Rest; D014188:Transposition of Great Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery*; D014655:Vascular Resistance / Q000502:physiology; D014661:Vasoconstriction / Q000502:physiology; D014664:Vasodilation / Q000502:physiology; D055815:Young Adult