Rheumatic Heart Disease

Rheumatic heart disease is a condition in which the heart valves are damaged by rheumatic fever (RF). It is an inflammatory disease caused by a bacterial infection. It can affect most connective tissues, especially those of the heart, joints, brain, and skin. Acute RF is common; however, it commonly occurs in children between 5 to 15 years old. Although the incidence of RF has declined sharply in many developed countries, the disease remains a major public health problem in many developing countries. An untreated group A streptococcal pharyngitis infection is the antecedent event that precipitates RF. Proper antimicrobial treatment of streptococcal pharyngitis with eradication of the organism virtually eliminates the risk of RF.

Rheumatic heart disease can involve any part of the heart. Rheumatic carditis is an infection affecting the endocardium, myocardium, and pericardium to various degrees. RF causes valvular heart disease by an autoimmune phenomenon whereby antibodies against streptococcal antigens cross-react with valvular tissue. The mitral and aortic valves are the most common valves involved. Clinically, rheumatic carditis is almost always associated with a murmur of valvulitis (an extra sound, which can be caused by the passage of blood through a damaged valve). Healing of the rheumatic valvulitis may cause fibrous thickening and adhesion, resulting in the most serious complications of RF: valvular stenosis and regurgitation. A stenotic valve cannot open completely, so blood is pumped through a smaller-than-normal opening. A valve also may not be able to close completely; this leads to regurgitation (blood leaking back through the valve when it should be closed).

Eventually, damaged heart valves can lead to serious cardiac problems. Their severity depends on the extent of the damage and the location of heart valves affected. The most serious condition is congestive heart failure in which the heart muscle is weakened and is not able to fully pump blood out of the heart to the rest of the organs.

The best strategy against rheumatic heart disease is to prevent RF from occurring. This can be achieved by treating streptococcal pharyngitis with penicillin or other appropriate antibiotics. People who already have RF are more susceptible to recurrent infectious episodes and consequent heart damage. Therefore, these patients are given continuous monthly or daily antibiotic treatment. Patients with myocardial damage caused by RF are given prophylactic antibiotics for dental and surgical procedures. These measures help prevent bacterial endocarditis, a dangerous infection involving the lining of the heart and valves.