Inflammatory (dilated) cardiomyopathy caused by necrosis of myocytes
Infectious agents
Enterovirus (Coxsackie B) and adenovirus most common
Influenza A and B
Hepatitis B
Beta-hemolytic streptococcus
Mycoplasma
Mumps
CMV
Toxoplasma
Chagas (most common cause worldwide)
Trichinosis
Diphtheria
Lyme disease
COVID-19
Drugs
Doxorubicin
Cocaine
Enterovirus (Coxsackie B) and adenovirus most common
Influenza A and B
Hepatitis B
Beta-hemolytic streptococcus
Mycoplasma
Mumps
CMV
Toxoplasma
Chagas (most common cause worldwide)
Trichinosis
Diphtheria
Lyme disease
COVID-19
Doxorubicin
Cocaine
Acute
Viral cytotoxicity and focal necrosis
Subacute
Host's humoral/immune response leading to further cell injury
Chronic
Diffuse myocardial fibrosis and cardiac dysfunction
Viral cytotoxicity and focal necrosis
Host's humoral/immune response leading to further cell injury
Diffuse myocardial fibrosis and cardiac dysfunction
Myocarditis
Consider other causes of CHF
Endocarditis
Acute coronary syndromes 
Constrictive pericarditis
STEMI
Pericarditis
Non-STEMI