Sex-related differences in cardiomyopathies

Cardiomyopathies (CMPs) are a heterogeneous group of heart muscle diseases with several different phenotypes defined as myocardial disorders in which the heart muscle is structurally and functionally abnormal in the absence of coronary artery disease, hypertension, valvular heart disease and congenital heart disease sufficient to explain the observed myocardial abnormality. CMPs can be classified into one of the following, i.e. hypertrophic CMP (HCM), dilated CMP (DCM), arrhythmogenic right ventricular CMP (ARVC), restrictive CMP (RCM), and unclassified CMPs. Although an increasing number of CMPs are now recognized to have a genetic basis, single mutations are associated with phenotypic variability and may cause not only a specific CMP, but also several different CMPs. Recently, it has become evident that, along with environmental interactions, age and sex may affect the penetrance of disease genes thus determining the phenotypic expression of CMPs. Noteworthy, an increasing body of data indicates that sex plays an important role in various forms of CMPs. The mode of inheritance may affect the sex-related occurrence of CMPs. Also, sex is a relevant determinant of the clinical manifestation of CMPs, and sex-related characteristics can be found in all forms. Sex-specific aspects of clinical disease expression as well as potential modes of inheritance should be therefore taken into proper consideration in order to improve the diagnostic work-up and treatment strategy of CMPs in both sexes.