Published online by Cambridge University Press: 19 August 2008
The Long List is a comprehensive hierarchical system of coding and classification for the diagnosis and treatment of heart disease. Although originally aimed at the clinician or surgeon treating heart disease first appearing in infancy or childhood, it has now been enlarged to encompass abnormalities first diagnosed in fetal life, as well as heart disease first acquired during adult life. There are a total of 3,876 individual terms. For the most part, these are mutually exclusive and unambivalent, given the constraints of clinical ambiguities and differing cultures of practice. In addition, there are 564 qualifier terms. These provide additional detail to individual or multiple items, such as fine anatomical detail, the severity of a lesion, the size of an interposition shunt or conduit, or the material used to close a septal defect. Finally, there are a further 341 duplicate diagnostic or procedural terms included in the List to aid its use, as some terms may have relevance in multiple areas. For example, Hypoplastic left heart syndrome is found under congenital anomalies of the left ventricle as well as in the section dealing with the aortic valve. Thus, altogether the listing consists of 4,781 items. The System is hierarchically arranged, with a major division between diagnostic and therapeutic subhierarchies. The developmental history of the Long List has been published previously, and is detailed earlier in this supplement.