Myocarditis Around the World
Written by Leslie T. Cooper, MD
Myocarditis is an important cause of acute heart failure, sudden death and chronic dilated cardiomyopathy (DCM). The major long-term consequence of myocarditis is chronic dilated cardiomyopathy, but the pathways that lead to myocardial fibrosis and chronic cardiomyopathy are poorly understood.
Are the causes of myocarditis the same in all regions of the world?
A: In developed countries, viral infections commonly cause myocarditis; however, in the developing world, rheumatic carditis following streptococcal infection and certain bacterial infections, such as diptheria (due to Corynebacterium diphtheriae), still contribute to the global burden of disease. The rates of viral cardiomyopathy in most developing countries are not yet known because the tests to identify viruses in heart tissue are not widely available. For example, the age-standardized incidence of myocarditis due to Corynebacterium diphtheriae has been estimated at nearly 50 cases per 100 million worldwide with much higher incidence in patrs of the former Soviet Union.
What are the major knowledge gaps in the global burden of myocarditis?
A: The incidence and prevalence of myocarditis are unknown in most regions of the world. There is a need for inexpensive, sensitive and specific diagnostic tests that can be used in population based studies in regions without access to advanced imaging or cardiac catheterization laboratories. Also, the optimal strategy for diagnosing myocarditis in at risk populations such as children is controversial and based largely on expert opinion