Adult Echocardiography Practice Exam

In patients with chronic mitral regurgitation, the primary cardiac structure that would be expected to be enlarged is the left atrium. This enlargement occurs due to the volume overload that results from the regurgitant flow of blood from the left ventricle back into the left atrium during systole. Over time, this increased volume causes the left atrium to dilate in an attempt to accommodate the extra blood.

As the condition progresses, this enlargement can lead to a variety of complications, including atrial fibrillation, which is a common arrhythmia associated with left atrial dilation. Monitoring the size and function of the left atrium is crucial in the management of patients with chronic mitral regurgitation, as it can provide insight into the severity of the regurgitation and the impact on cardiac function.

While other structures such as the left ventricle may also undergo changes due to the volume overload, the left atrium is the most directly affected by the mechanism of mitral regurgitation.