Branch and Peripheral Pulmonary Stenosis Recommendations for Branch and Peripheral PS Referenced studies that support recommendations are summarized in Online Data Supplement 40. COR LOE Recommendations Diagnostic I B-NR For adults with peripheral or branch PS, ongoing surveillance is Therapeutic IIa B-NR In adults with peripheral or branch PA stenosis, PA dilation and stenting can be Synopsis Pulmonary branch and peripheral PS can be isolated, occur as part of a constellation of right ventricular out- flow tract (RVOT) obstruction, or be found in associa- tion with a syndrome (eg, Noonan, Alagille, Williams, maternal rubella exposure). Intervention decisions are typically based on symptoms, distribution of pulmonary blood flow, RV function, and RV systolic pressure. TTE is a good modality to obtain RV pressure and function but does not adequately image the peripheral pulmonary arteries. Alternative imaging (eg, CMR, CCT) can vis- ualize anatomic obstructions and branch PA anatomy. In addition, CMR and pulmonary perfusion testing can quantify relative pulmonary blood flow. CLINICAL STATEMENTS AND GUIDELINES 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 24 for routine testing and follow-up intervals. Recommendation-Specific Supportive Text 1. Cardiac follow-up and imaging may include evaluation of RV pressure; quantifying relative pulmonary blood flow and imaging for evidence of residual lesions or PA obstruction or aneu- rysm at sites of prior intervention; and in-stent stenosis and/or stent fracture (the latter often best seen by fluoroscopy). 