USMLE (United States Medical Licensing Examination) Step 1 Practice Exam

What type of LVH is characterized by volume overload?

1. Concentric LVH

2. Eccentric LVH

3. Left atrial enlargement

4. Left ventricular aneurysm

The correct answer is: Eccentric LVH

Eccentric left ventricular hypertrophy (LVH) is associated with volume overload. This condition typically arises in response to a sustained increase in blood volume within the heart, commonly due to conditions such as regurgitant valve lesions (e.g., mitral or aortic regurgitation) or other forms of heart failure where the heart needs to accommodate a larger than normal amount of blood. In eccentric LVH, the ventricular walls become thicker, and the overall size of the left ventricle enlarges as it adapts to the increased volume workload. The heart chambers have to stretch to accommodate the excess blood, leading to both dilation and hypertrophy of the myocardium, which is a hallmark of eccentric hypertrophy. Understanding this concept is crucial for recognizing the underlying pathophysiological processes in various cardiac conditions. In contrast, concentric LVH directly results from pressure overload where the muscle thickens without significant dilation, primarily as a response to hypertension or aortic stenosis. Left atrial enlargement and left ventricular aneurysms are different cardiac disorders not primarily defined by the characteristics of LVH related to volume overload.