Supravalvular Aortic Stenosis Recommendations for Supravalvular Aortic Stenosis Referenced studies that support recommendations are summarized in Online Data Supplement 37. COR LOE Recommendations Diagnostic I C-LD Aortic imaging using TTE, TEE, CMR, or CTA is recommended in adults with Williams syndrome or patients suspected of having supravalvular aortic stenosis.S4.2.5-1 I C-LD Coronary imaging is recommended in patients with Williams syndrome and supravalvular aortic stenosis presenting with symptoms of coronary ischemia.S4.2.5-2 S4.2.5-4 Therapeutic I B-NR Surgical repair is recommended for adults with supravalvular aortic stenosis (discrete or diffuse) and symptoms or decreased LV systolic function deemed secondary to aortic I C-LD Coronary artery revascularization is recommended in symptomatic adults with supravalvular aortic stenosis and coronary Synopsis Supravalvular aortic stenosis is a relatively rare condition o- verall but is seen commonly in patients with Williams syn- drome or homozygous familial hypercholesterolemia. The stenotic ridge tends to occur distal to the coronary artery orifices at the sinotubular junction. In addition to pressure load physiology similar to other causes of LVOT obstruc- tion, coronary abnormalities can occur, including signifi- cant coronary ostial stenosis resulting in risk of SCD and Unlike subAS or valvular aortic stenosis, the coronary arteries are exposed to the higher pressure generated by the supravalvular obstruction. See Section 3.3 for recommendations on who should perform surgeries, cardiac catheterization, and other procedures in these patients; Section 3.4 for rec- ommendations on diagnostic evaluation; and Table 20 for routine testing and follow-up intervals. Table 20. Supravalvular Aortic Stenosis: Routine Follow-Up and Testing Intervals Frequency of Routine Follow-Up and Testing Physiological Stage A* (mo) Physiological Stage B* (mo) Physiological Stage C* (mo) Physiological Stage D* (mo) *See Tables 3 and 4 for details on the ACHD AP classification system. 