Aortic Diameter Growth in Children With a Bicuspid Aortic Valve

Abstract

Knowledge of aortic growth in patients with bicuspid aortic valve (BAV) is essential to identify patients at risk for dissection, but data on children remain unclear. We retrospectively evaluated the aortic diameters of all pediatric BAV patients, identified through an echocardiographic database (2005 to 2013). Medical records were reviewed and aortic diameters re-measured on echocardiographic images at diagnosis and if available on variable mid- and endpoints follow-up. Dilatation (z-score >2) was based on 2 different z-score equation methods (Gautier/Campens). In 234 of the total 250 BAV patients, aortic diameters were analyzed; median age was 6.1 years (interquartile range 1.7 to 10), of which 63% were male. Aortic coarctation was present in 81 (36%) patients, 23% had a ventricular septal defect. BAV morphology according to Sievers was as follows: type 0 in 128 patients (55%), type 1 in 96 (41%), and type 2 in 10 (4%). Ascending aortic (AA) dilatation was present in 24% (Gautier) and 36% (Campens) at inclusion. Median follow-up was 4.7 years. The AA was the only location where mean z-scores progressed significantly with age: 0.06 (Gautier) and 0.09 (Campens) units per year between ages 5 and 15 years. Associations for higher AA z-scores at older age were an initial z-score >2 (p <0.001) and aortic valve stenosis (p <0.05). Neither dissection nor preventive aortic surgery occurred. In conclusion, only the AA seems at risk for complication, although no aortic complications occurred in this pediatric BAV cohort. BAV morphology seems associated with larger AA z-scores and valvular dysfunction.

Bicuspid aortic valve formation: Nos3 mutation leads to abnormal lineage patterning of neural crest cells and the second heart field

“…The tricuspid aortic valve (TAV) has a crucial role in maintaining unidirectional blood flow from the left ventricle into the systemic circulation. Abnormalities in aortic valve morphology, as seen in the case of the bicuspid aortic valve (BAV), have been linked to valvular regurgitation, stenosis and progressive thoracic aortic aneurysm development ( Ward, 2000 ; Verma and Siu, 2014 ; Sievers et al, 2015 ; Merkx et al, 2017 ). A BAV is currently accepted as a congenital anomaly with a high incidence, occurring in 0.5-2% of the Western population ( Roberts, 1970 ; Ward, 2000 ; Hoffman and Kaplan, 2002 ).…”

Bicuspid aortic valve: different clinical profiles for subjects with versus without repaired aortic coarctation

“…A small number of studies in children have found that children with BAV-CoA have less AS/AR than children with pure BAV 4 and less valve intervention. 5 While this indicates that repaired CoA does not appear to have deleterious effects on the BAV early in life, the consequences of any prolonged aberrations relating to the repaired CoA may not yet have manifested in this young cohort. No studies of adults have specifically studied the impact of CoA on BAV valve complications, however, one large study of 642 adults with BAV, of whom 25% had a history of CoA, found that a significantly higher proportion of adults with CoA did not experience valve and aortic complications, 6 suggesting that in fact patients with coarctation have a better prognosis.…”

Bicuspid Aortic Valve: An Update in Morphology, Genetics, Biomarker, Complications, Imaging Diagnosis and Treatment

“…Pediatric BAV, although similar to adult BAV, has different characteristics in disease development and treatment. According to Sievers classification, BAV morphology including type 0 (55%), type 1 (41%), and type 2 (4%) in children (Merkx et al, 2017). At an early stage, some children with well-functioning BAV have abnormalities in some parameters of diastolic function of LV and even all parameters of proximal and distal ascending aortic elasticity.…”

“…For the patient with isolated, normal functioning BAV, echocardiography could be used to monitor development of BAV associated complications (Merkx et al, 2017). Due to the inaccuracy in measurement of aortic valve annular eccentricity through 2D echocardiography, therefore, 3D echocardiography could be a better choice to evaluate the AV annulus which has the shape of ellipse and keeps the same in all patients (Chamberland et al, 2015).…”