Patients with evidence of resting or stress-induced ischemia in the absence of obstructive coronary artery disease and in the presence of moderate subAS (maximum gradient >30 mm Hg and <50 mm Hg) may benefit from surgical relief of subAS.S4.2.3-9 4. Discrete subAS tends to be progressive with age, and patients with a resting maximum gradient 50 mm Hg are more likely to have progressive subAS and concomitant moderate or severe aortic Therefore, surgical inter- vention may be considered in the asymptomatic patient with severe subAS. Tunnel-type subAS, which is often associated with a small aortic valve annulus, is associated with worse long-term out- comes and a higher risk of recurrence after sur- gical resection compared with subAS caused by a discrete membrane.S4.2.3-5 Surgical intervention on patients with asymptomatic subAS (maximum gradient 50 mm Hg) with preserved LV ejection fraction may delay progression of, or improve the degree of, aortic valve regurgitation. SubAS in adults may progress more slowly than in children, and although mild AR is common, it may not be progressive in medium-term follow-up.S4.2.3-10 4.2.4. Congenital Valvular Aortic Stenosis Recommendations for Congenital Valvular Aortic Stenosis Referenced studies that support recommendations are summarized in Online Data Supplement 34. COR LOE Recommendations Diagnostic I B-NR Adults with bicuspid aortic valve should be evaluated for coarctation of the aorta by clinical examination and imaging IIa B-NR It is reasonable to screen first-degree relatives of patients with bicuspid aortic valve or unicuspid aortic valve with echocardiography for valve disease and Therapeutic IIb B-NR In adults with bicuspid aortic valve stenosis and a noncalcified valve with no more than mild AR meeting indications for intervention it may be reasonable to treat with balloon valvuloplasty.S4.2.4-6 Synopsis Indications for aortic valve replacement according to generally apply. 