Bicuspid Aortic Valve in Infants without Severe Congenital Heart Defects: Early Echocardiographic Findings Guide...

Bicuspid aortic valve (BAV) is one of the most common congenital heart defects (CHDs). However, guidelines for imaging surveillance frequency are not well established among young children, particularly those diagnosed during infancy without hemodynamically significant associated congenital lesions.

The Mayo Clinic echocardiography database was retrospectively searched for infants (age <1 year) diagnosed with BAV from 2001 to 2019. We initially identified 307 patients, and of these, 204 (66%) patients with BAV and concomitant significant CHD were excluded. Therefore, 103 (34%) patients with isolated BAV without critical valvulopathy and/or BAV with simple CHD (atrial septal defects, muscular ventricular septal defects, and/or patent ductus arteriosus) were included for further analysis.

Overall, 103 infants (68% male) with isolated BAV or BAV with simple CHD underwent their first echocardiogram at a median age of 8 days (interquartile range [IQR], 2-84 days; range, 0-349 days). A total of 92 (89%) subjects had at least 1 follow-up visit and most recent echocardiogram at a median age of 8.6 years (IQR, 3.7-13.6 years) with a total clinical follow-up of 791 patient-years. Bicuspid aortic valve was present as an isolated lesion in 43% (44/103), while concomitant simple CHD was present in 57% (59/103) of infants. The most common indication for an echocardiogram was presence of a murmur (68%, 70/103). The first echocardiogram demonstrated aortic regurgitation (AR) in 4% (4/92) and aortic stenosis (AS) in 30% (28/92). A total of 10 aortic valve procedures were performed in 8 patients (9%), with AS (P < .001) and ascending aortic Z score ≥2 (P = .006) on the index echocardiogram significantly associated with risk of aortic valve intervention. Among 61 infants without AS or AR on their first echocardiogram (61/92), none required any valvular intervention at a median follow-up age of 6.0 years (IQR, 2.1-10.8 years). Among 28 infants who had AS (any degree) on their first echocardiogram, 8 (29%) required valvular intervention by a median age of 12.4 years (IQR, 7.2-17.7 years) and all had at least moderate AS at the baseline echocardiogram. Aortic stenosis on the baseline echocardiogram was predictive of not only aortic valve intervention (P < .001) but also progression of AR (P = .007) and ascending aorta dilation (P = .0002) at last follow-up. Among 35 infants with aortopathy at their first echocardiogram, none required intervention on the aorta at a median age of 8.8 years (IQR, 4.0-14.2 years). Overall, 4 patients died, with no deaths related to cardiac disease.

Infants with normally functioning BAV without severe CHD did not develop significant valvulopathy or aortopathy over the first few years of life and required no interventions on the aortic valve or aorta. Conversely, those with more than mild AS or ascending aortic dilation at first echocardiogram incurred higher risk of valvular intervention, valvulopathy, and aortopathy progression. Therefore, initial valve and aortic pathology should guide frequency of follow-up surveillance imaging.