Epidemiology of acquired valvular heart disease.

Population-based studies including systematic echocardiographic examinations are required to assess the prevalence of valvular heart disease. In industrialized countries, the prevalence of valvular heart disease is estimated at 2.5%. Because of the predominance of degenerative etiologies, the prevalence of valvular disease increases markedly after the age of 65 years, in particular with regard to aortic stenosis and mitral regurgitation, which accounts for 3 in 4 cases of valvular disease. Rheumatic heart disease still represents 22% of valvular heart disease in Europe. The prevalence of secondary mitral regurgitation cannot be assessed reliably but it seems to be a frequent disease. The incidence of infective endocarditis is approximately 30 cases per million individiuals per year. Its stability is associated with marked changes in its presentation. Patients are getting older and staphylococcus is now becoming the microorganism most frequently responsible. Heath care-associated infections are the most likely explanation of changes in the microbiology of infective endocarditis. In developing countries, rheumatic heart disease remains the leading cause of valvular heart disease. Its prevalence is high, between 20 and 30 cases per 1000 subjects when using systematic echocardiographic screening. In conclusion, the temporal and geographical heterogeneity illustrates the effect of socioeconomic status and changes in life expectancy on the frequency and presentation of valvular heart disease. A decreased burden of valvular disease would require the elaboration of preventive strategies in industrialized countries and an improvement in the socioeconomic environment in developing countries.