Acute rheumatic fever should resolve in 4 weeks. Some children recover completely while others are left with permanent damage to their hearts. Acute rheumatic fever tends to recur and the risk of permanent heart damage (rheumatic heart disease) increases with each acute attack. Every effort must therefore be made to prevent repeat attacks.

One or more attacks of acute rheumatic fever can cause permanent damage to one or more heart valves. This is called chronic rheumatic heart disease. Leaking of the mitral valve (mitral incompetence) or narrowing of the mitral valve (mitral stenosis) are the most common permanent valve defects. Damage to a valve or damage to the heart muscle can cause heart failure.