ACHD indicates adult congenital heart disease; AP, anatomic and physiological; ASD, atrial septal defect; AVSD, atrioventricular septal defect; CCTGA, congenitally corrected transposition of the great arteries; CHD, congenital heart disease; d-TGA, dextro-transposition of the great arteries; FC, functional class; HCM, hypertrophic cardiomyopathy; l-TGA, levo-transposition of the great arteries; NYHA, New York Heart Association; TGA, transposition of the great arteries; and VSD, ventricular septal defect. Table 4. Continued CHD Anatomy* (Continued) CLINICAL STATEMENTS AND GUIDELINES has a small atrial septal defect (ASD), but whose symp- toms are related to diastolic HF, chronic kidney disease caused by hypertension and diabetes mellitus, and mod- erate aortic stenosis is well-suited to be followed ac- cording to existing guidelines for those diseases, rather than according to the ACHD AP classification for the ASD. Nevertheless, the added hemodynamic complexity brought by the ASD must be kept in mind. Throughout this document, the ACHD AP classifica- tion is used to help guide resource utilization, including ACHD consultation and routine diagnostic studies. 3. GENERAL PRINCIPLES See Online Data Supplements 1 and 2 for additional data supporting this section. 3.1. ACHD Program Patients with complex CHD have generally better out- comes when cared for in an integrated, collaborative, and multidisciplinary program.S3.1-1 Many medical is- sues in patients with ACHD involve cardiac sequelae, and the diagnosis and management may require car- diac anesthesiologists, electrophysiologists, and in- terventional cardiologists; imaging services such as cardiovascular magnetic resonance (CMR)/cardiac computed tomography (CCT); and pulmonary hy- pertension services with expertise in ACHD (Table 5). Appropriate specialty care must be available to address pregnancy, acquired cardiovascular disease, and acute noncardiac illness complicating CHD, man- agement of which is frequently more complicated in patients with ACHD. 