The damaged valves may result in heart failure and also increase the risk of atrial fibrillation and infection of the valves. Pathophysiology
Rheumatic fever is a systemic disease affecting the connective tissue around arterioles, and can occur after an untreated strep throat infection, specifically due to group A streptococcus (GAS), Streptococcus pyogenes. The similarity between antigens of Streptococcus pyogenes and multiple cardiac proteins can cause a life-threatening type II hypersensitivity reaction. Usually, self reactive B cells remain anergic in the periphery without T cell co-stimulation. During a streptococcal infection, mature antigen-presenting cells such as B cells present the bacterial antigen to CD4+T cells which differentiate into helper T2 cells. Helper T2 cells subsequently activate the B cells to become plasma cells and induce the production of antibodies against the cell wall of Streptococcus. However the antibodies may also react against the myocardium and joints, producing the symptoms of rheumatic fever. S. pyogenes is a species of aerobic, cocci, gram-positive bacteria that are non-motile, non-spore forming, and forms chains and large colonies.S. pyogenes has a cell wall composed of branched polymers which sometimes contain M protein, a virulence factor that is highly antigenic. The antibodies which the immune system generates against the M protein  may cross-react with heart muscle cell protein myosin, heart muscle glycogen and smooth muscle cells of arteries, inducing cytokine release and tissue destruction. However, the only proven cross-reaction is with perivascular connective tissue. This inflammation occurs through direct attachment of complement and Fc receptor-mediated recruitment of neutrophils and macrophages.
The risks, benefits, and alternative treatments must always be considered when administering aspirin and aspirin-containing products in children and teenagers. Ibuprofen for pain and discomfort and corticosteroids for moderate to severe inflammatory reactions manifested by rheumatic fever should be considered in children and teenagers. Vaccine
No vaccines are currently available to protect against S. pyogenes infection, although research is underway to develop one. Difficulties in developing a vaccine include the wide variety of strains of S. pyogenes present in the environment and the large amount of time and people that will be needed for appropriate trials for safety and efficacy of the vaccine. Infection
People with positive cultures for Streptococcus pyogenes should be treated with penicillin as long as allergy is not present. The use of antibiotics will not alter cardiac involvement in the development of rheumatic fever. Some suggest the use of benzathine benzylpenicillin.Monthly injections of long-acting penicillin must be given for a period of five years in patients having one attack of rheumatic fever. If there is evidence of carditis, the length of therapy may be up to 40 years. Another important cornerstone in treating rheumatic fever includes the continual use of low-dose antibiotics (such as penicillin, sulfadiazine, or erythromycin) to prevent recurrence. Inflammation
While corticosteroids are often used, evidence to support this is poor. Salicylates are useful for pain.Steroids are reserved for cases where there is evidence of an involvement of the heart. The use of steroids may prevent further scarring of tissue and may prevent the development of sequelae such as mitral stenosis.