Almost every day brings new reports of a “rare” (“orphan”) disease – a disease that requires multidisciplinary knowledge and particular caution in making diagnostic and therapeutic decisions.
The Classification of Rare Cardiovascular Diseases (RCD) is aimed at (1) facilitating recognition of RCDs, and (2) grouping the expertise in the main fields of RCDs.
The classification provides a systemic framework for clinical examples selected from a broad group of patients who have been consulted in the CRCD on a regular basis by national and international experts during live videoconferences.
RCD Classification presented in Table 1 and published simultaneously in the Journal of Rare Cardiovascular Diseases is based on the CRCD experience of over 300 patients consulted in the years 2006–2013 (many of whom were diagnosed and treated in the CRCD) and takes into consideration the majority of publications available through PubMed.
RCD Classification encompasses the diseases whose major pathological mechanism affects the cardiovascular system. RCD Classification*accommodates the intensity of clinical symptoms and pathology concerning the systemic and pulmonary circulation (Class I and Class II), the heart and myocardium (Class III), congenital heart diseases (class IV), and rhythm and conduction disorders (Class V). Cardiovascular diseases in oncological patients (Class VI) and those in pregnant patients are classified separately (Class VI and Class VII, respectively). There are also overlapping syndromes and diseases that cannot be unequivocally classified into any of the Classes I to VII, that is represented by Class VIII.
The main classes of the RCD classification include:
Class I – rare diseases of systemic circulation
Class II – rare diseases of pulmonary circulation
Class III – rare diseases of the heart (cardiomyopathies)
Class IV – rare congenital cardiovascular diseases
Class V – rare arrhythmias
Class VI – cardiac tumors and cardiovascular diseases in malignancy
Class VII – cardiovascular diseases in pregnancy
Class VIII – unclassified rare cardiovascular diseases
RCD Classification is presented in Table 1. It is listed by groups and subgroups as appropriate. It contains RCD Classification code and the code of International Classification of Diseases (ICD-10). The main classes are arranged in order from class I to class VIII. Each entity or group of entities is assigned a unique RCD Classification code. Coding of Class VII is described in a relevant commentary in the Table 1. Consecutive unclassified rare cardiovascular cases included in Class VIII are assigned subsequent code according to the order of publication on the CRCD webpage – www.crcd.eu or in the Journal of Rare Cardiovascular Diseases.
As this classification is regarded the pioneering attempt to systematize rare cardiovascular diseases the authors of this textbook are, indeed, aware of its imperfections and limitations. Therefore, presenting this classification we sincerely encourage the Readers to provide their solid feedback. Constructive contributions will be recognized.