Imaging can identify the presence of a BAV and aortic dilation, but there is a paucity of data on the cost-effectiveness of this approach and whether earlier diagnosis would improve long-term clinical outcomes.6,11 5.1.1.2. Diagnostic Testing: Routine Follow-Up Recommendations for Diagnostic Testing: Routine Follow-Up of Patients With a BAV Referenced studies that support the recommendations are summarized in Online Data Supplement 18. COR LOE Recommendations In patients with BAV and a diameter of the aortic sinuses or ascending aorta of 4.0 cm, lifelong serial evaluation of the size and morphology of the aortic sinuses and ascending aorta by echocardiography, CMR, or CT angiography is reasonable, with the examination interval determined by the degree and rate of progression of aortic dilation and by family history.1 5 In patients with a BAV who have undergone AVR, continued lifelong serial interval imaging of the aorta is reasonable if the diameter of the aortic sinuses or ascending aorta is 4.0 Synopsis Patients with BAV with and without associated aortic aortopathy require lifelong surveillance. Because pro- gression of valve disease and growth of the aorta can occur in the absence of symptoms, diagnostic imaging plays an integral role in the surveillance process. Recommendation-Specific Supportive Text 1. 