(Continued) CLINICAL STATEMENTS AND GUIDELINES of the great arteries, and TOF, amongst others. In every patient, anatomic and physiological variables should be considered. In using Tables 3 and 4, a patient should be classified based on the highest relevant anatomic or physiological feature. For example, a normotensive pa- tient with repaired CoA, normal exercise capacity, and normal end-organ function would be ACHD AP classifi- cation IIA, whereas an otherwise similar patient with as- cending aortic diameter of 4.0 cm would be ACHD AP classification IIB, and if moderate aortic stenosis were also present, the ACHD AP classification would be IIC. Patients with ACHD may have baseline exercise limitations, cyanosis, end-organ dysfunction, or other clinically important comorbidities related to their CHD. They are also at risk of HF, arrhythmias, sudden car- diac death (SCD), and development or progression of cardiac symptoms such as dyspnea, chest pain, and exercise intolerance. Concomitant valvular disease or aortic pathology may be present. There are growing data regarding the prognostic implications of these variables in patients with ACHD, but not the abun- dance of data available for patients with acquired The variables forming part of the ACHD AP classifi- cation (Table 3) were selected because data exist sug- gesting their importance in prognosis, management, or quality of life (QoL). As new data become availa- ble, we expect changes in the relative weights attrib- uted to the components of the ACHD AP classification and perhaps new components, resulting in a scheme that ever more precisely tracks overall severity of di- sease and need for more or less intensive follow-up and management. Similar to the New York Heart Association (NYHA) classification of functional status, patients may move from one ACHD AP classification to another over time. 