Epidemiology and etiology of cardiomyopathy

Background—Cardiomyopathy, an often irreversible form of heart muscle disease that is associated with a dismal outcome, is endemic in Africa. The primary objective of this review was to summarize the current state of knowledge on the epidemiology and etiology of cardiomyopathy in people living in Africa and to identify new avenues for research. Methods and Results—We searched MEDLINE (January 1, 1966, through February 12, 2005) and reference lists of articles for relevant references. Unlike other parts of the world in which cardiomyopathy is rare, dilated cardiomyopathy is a major cause of heart failure throughout Africa. Similarly, peripartum cardiomyopathy is ubiquitous on the continent, with an incidence ranging from 1 in 100 to 1 in 1000 deliveries. There is an apparent marked regional variation in the pathogenesis of dilated cardiomyopathy and peripartum cardiomyopathy, underlining the heterogeneity of causative factors in these conditions. By contrast, endomyocardial fibrosis is restricted to the tropical regions of East, Central, and West Africa. Although the pathogenesis of endomyocardial fibrosis is not fully understood, it seems that the conditioning factors are geography and diet, the triggering factor may be an as yet unidentified infective agent, and the perpetuating factor is eosinophilia. Although epidemiological studies are lacking, hypertrophic cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy seem to have characteristics similar to those of other populations elsewhere in the world. Conclusions—There is a need for large-scale epidemiological studies of the incidence, prevalence, determinants, an