Which valve is the second most commonly affected by rheumatic heart disease?

• A. Aortic Valve (AOV)
• B. Mitral Valve (MV)
• C. Tricuspid Valve (TV)
• D. Pulmonary Valve (PV)

Answer: (A)

Rheumatic heart disease results from an immune-mediated injury after a streptococcal infection, leading to chronic inflammation and scarring of heart valves. The left-sided valves are affected first because they endure higher pressures. The mitral valve is the most commonly involved because it bears the highest stress and is most susceptible to rheumatic inflammation, often leading to stenosis or regurgitation over time. The aortic valve follows as the second most commonly affected valve, as it also undergoes inflammatory damage from the same process, causing aortic stenosis or regurgitation in many patients.

The tricuspid and pulmonary valves are involved far less often, and when they are affected, it typically occurs alongside left-sided valve disease rather than as isolated involvement. So, the second most commonly affected valve in rheumatic heart disease is the aortic valve.