A child had rheumatic fever at age 6. What are the most significant potential long-term complications?

Rheumatic fever is an inflammatory autoimmune condition triggered by group A beta-hemolytic Streptococcus (Streptococcus pyogenes) pharyngeal infection. It affects the heart, joints, skin, and CNS. The most serious long-term complication is rheumatic heart disease, characterized by fibrosis and scarring of the heart valves — particularly the mitral valve (mitral stenosis or regurgitation). Repeated episodes worsen valvular damage. Patients with rheumatic heart disease and valvular damage may require antibiotic prophylaxis before dental procedures. Rheumatic fever is caused by Streptococcus, NOT herpes or Staphylococcus.