Yield of echocardiographic screening of first-degree relatives of children with bicuspid aortic valve

Abstract

Abstract Background Bicuspid aortic valve (BAV) is the most common congenital heart defect, affecting 0.8% of new-borns. BAV is associated with valve dysfunction, as well as an increased risk of aortopathy. The prevalence of BAV in first-degree relatives of symptomatic BAV patients, is reported to be 5–10%. First-degree relatives also have an increased risk of aortic dilatation, independently of aortic valve morphology. Purpose The purpose of the study was to determine the prevalence of BAV, associated valve dysfunction and aortopathy in first-degree relatives to children diagnosed with BAV neonatally in a population-based study. Methods Between April 2016 and October 2018 all expecting parents at three major maternity centres were offered inclusion in a large-scale population study with focus on congenital heart disease (N≥25,000). A total of 197 children, in 196 families, were diagnosed with BAV. All first-degree relatives, including half-siblings, were offered inclusion in the follow-up study with standardized transthoracic echocardiography. Adults were also examined with transoesophageal echocardiography. Aorta diameters were measured at the AV annulus, sinuses of Valsalva, sino-tubolare junction and in the proximal ascending aorta. Aortic dilatation in children were defined as any aortic root or ascending aorta diameter ≥2 standard deviations (SD) from the expected mean, calculated as z-score using formulas from the Paediatric Heart Network Echocardiogram Database. In adults, aortic dilatation was defined as aortic root and/or ascending aorta diameters indexed to body surface area (BSA) exceeding normal reference values established by the European Association of Cardiovascular Imaging. Results In total, 352 first-degree relatives (242 adults [35.3 years SD 5.5] and 110 children [4.5 years, SD 3.5] were included. BAV was diagnosed in 24 relatives (6.8%). BAV could not be conclusively ruled out in 52 relatives (14.8%), who are awaiting further examination with transoesophageal echocardiography. Dilatation of the aortic root was observed in 8 adult relatives and in 17 children (7.1%). Aortic valve regurgitation was observed in 23 relatives (6.5%). In total 58 relatives (16.2%) were diagnosed with either BAV, dilated aorta, or aortic regurgitation. Conclusion One in fifteen first-degree relatives to children diagnosed with BAV neonatally, also had BAV, corresponding to >8 fold increase in prevalence compared with the background population. One in six relatives had BAV, dilated aorta, or aortic regurgitation. These findings are of importance for family-screening programs of BAV. Funding Acknowledgement Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Danish Children's Heart Association