American Board of Internal Medicine (ABIM) Certification Practice Exam

What characterizes aortic valve replacement indication for asymptomatic patients with aortic regurgitation?

1. Severe symptoms of regurgitation

2. Chronic severe aortic regurgitation and LV ejection fraction ≤50%

3. Age over 70

4. Presence of chest pain

The correct answer is: Chronic severe aortic regurgitation and LV ejection fraction ≤50%

Aortic valve replacement in asymptomatic patients with aortic regurgitation is primarily indicated when there are objective measures indicating that the heart is not functioning adequately despite the lack of symptoms. In cases of chronic severe aortic regurgitation, the situation becomes critical when the left ventricular ejection fraction (LV EF) drops to 50% or less. This threshold signifies a compromised myocardial function, indicating that the ventricle is under stress from volume overload due to the regurgitant flow. Patients may not exhibit symptoms until significant damage has already occurred, which is why routine assessment of the LV function is vital. When the LV EF falls below this level, the risk of symptomatic heart failure, poor prognosis, and potential irreversible myocardial damage increases, making surgical intervention necessary to preserve heart function and improve long-term outcomes. Age and the presence of symptoms are not definitive criteria for surgical intervention in asymptomatic patients. Although age and symptoms are relevant factors in the overall management, they do not exclusively dictate the need for valve replacement in the context of severe aortic regurgitation, making this choice particularly important in clinical decision-making.