American Board of Internal Medicine (ABIM) Certification Practice Exam

What ERO value is characteristic of severe aortic regurgitation?

1. Less than 0.10 cm2

2. Between 0.10 cm2 and 0.29 cm2

3. Between 0.30 cm2 and 0.40 cm2

4. Greater than 0.3 cm2

The correct answer is: Greater than 0.3 cm2

In the context of aortic regurgitation, the effective regurgitant orifice area (EROA) is a crucial measurement used to determine the severity of the condition. Severe aortic regurgitation is typically characterized by a significantly enlarged EROA, which indicates a greater volume of blood flowing back from the aorta into the left ventricle during diastole. An EROA greater than 0.30 cm² is consistent with severe aortic regurgitation, reflecting a substantial regurgitant flow that can lead to volume overload of the left ventricle. This overload, if unaddressed, can progress to left ventricular dilation and ultimately heart failure due to the inability of the heart to compensate for the increased volume load effectively. The values associated with less than 0.10 cm², between 0.10 cm² and 0.29 cm², and between 0.30 cm² and 0.40 cm² indicate varying degrees of regurgitation severity, with only the measurement above 0.30 cm² firmly indicating severe aortic regurgitation. Hence, when evaluating the severity of aortic regurgitation, an EROA greater than 0.30 cm²