Rheumatic Disease and Aortic Valve Stenosis: Understanding the Connection

Aortic valve stenosis can have various underlying causes, one of which is rheumatic disease. Rheumatic heart disease, in particular, often results from an infection caused by group A Streptococcus bacteria. Following this infection, the body's immune system produces antibodies to fight the bacteria. However, these antibodies can mistakenly attack the heart valves due to similarities between certain heart tissue antigens and those of the bacteria, leading to valve damage over time.

How Rheumatic Fever Affects Heart Valves

When rheumatic fever occurs, it can cause inflammation and scarring of the heart valves. This damage typically progresses through processes such as fibrosis, calcification, and leaflet thickening. While both the mitral and aortic valves can be affected, they respond differently due to their structural differences. The mitral valve has a parachute-like structure with chordae tendineae, making it more prone to fusion of the leaflets, which often leads to mitral stenosis. In contrast, the aortic valve, which has a semilunar structure, tends to undergo thickening and calcification rather than fusion.

Rheumatic vs. Rheumatoid Conditions

It's important to distinguish between rheumatic fever and rheumatoid arthritis. Rheumatic fever is a post-infectious complication triggered by a streptococcal infection and primarily affects the heart valves. On the other hand, rheumatoid arthritis is a chronic autoimmune disorder that mainly impacts joints and can also affect other organs. Although both conditions involve inflammation and immune responses, they belong to different medical categories—rheumatic heart disease falls under post-infectious complications, while rheumatoid diseases are classified as autoimmune disorders.

Long-Term Implications of Valve Damage

Over time, untreated rheumatic valve damage can lead to significant complications, including heart failure, arrhythmias, and increased risk of infective endocarditis. Aortic stenosis resulting from rheumatic disease may progress slowly, often remaining asymptomatic for years before causing noticeable symptoms such as shortness of breath, chest pain, or fainting. Early diagnosis and management are crucial to preventing severe complications and improving long-term outcomes.