Also, endocarditis prophylaxis is indicated before dental, gastrointestinal or genitourinary procedures. Mild to moderate aortic regurgitation should be followed with echocardiography and a cardiac stress test once every 1–2 years. In severe moderate/severe cases, patients should be followed with echocardiography and cardiac stress test and/or isotope perfusion imaging every 3–6 months. Mitral stenosis
For patients with symptomatic severe mitral stenosis, percutaneous balloon mitral valvuloplasty (PBMV) is recommended. If this procedure fails, then it may be necessary to undergo mitral valve surgery, which may involve valve replacement, repair, or commisurotomy. Anticoagulation is recommended for patients that have mitral stenosis in the setting of atrial fibrillation or a previous embolic event. No therapy is required for asymptomatic patients. Diuretics may be used to treat pulmonary congestion or edema. Mitral regurgitation
Surgery is recommended for chronic severe mitral regurgitation in symptomatic patients with left ventricular ejection fraction (LVEF) of greater than 30%, and asymptomatic patients with LVEF of 30-60% or left ventricular end diastolic volume (LVEDV) > 40%. Surgical repair of the leaflets is preferred to mitral valve replacement as long as the repair is feasible. Mitral regurgitation may be treated medically with vasodilators, diuretics, digoxin, antiarrhythmics, and chronic anticoagulation. Mild to moderate mitral regurgitation should be followed with echocardiography and cardiac stress test every 1–3 years. Severe mitral regurgitation should be followed with echocardiography every 3–6 months. Epidemiology
In the United States, about 2.5% of the population has moderate to severe valvular heart disease.
Cardiac involvement is dependent on the cross-reaction of antibodies directed against M proteins produced by bacteria with human proteins present in the myocardium or endocardium (although acute rheumatic fever may present as pancarditis with additional involvement of the pericardium). This results in generalized inflammation in the heart, producing acute erosions and vegetations with fibrin deposition in the mitral valve that may be followed by chronic changes over years to decades, including shortening of the chordae tendinae and thickening or fusion of the mitral leaflets, leading to a severely compromised "buttonhole" or "fish mouth" valve.In 70% of cases rheumatic heart disease involves only the mitral valve, while 25% of cases involve both the aortic and mitral valves. Involvement of other heart valves without damage to the mitral is exceedingly rare. Mitral stenosis is almost always caused by rheumatic heart disease. Less than 10% of aortic stenosis is caused by rheumatic heart disease. Rheumatic fever can also cause chronic mitral and aortic regurgitation.While developed countries once had a significant burden of rheumatic fever and rheumatic heart disease, medical advances and improved social conditions have dramatically reduced their incidence. Many developing countries, as well as indigenous populations within developed countries, still carry a significant burden of rheumatic fever and rheumatic heart disease and there has been a resurgence in efforts to eradicate the diseases in these populations. Among persons who have experienced rheumatic fever, long-term intramuscular antibiotic therapy is used as secondary prophylaxis against additional streptococcal infections, which can contribute to progression of rheumatic heart disease.