Which condition is suggested by increased left atrial size, possible left atrial thrombus, and enlargement of the right atrium and right ventricle?

Which condition is suggested by increased left atrial size, possible left atrial thrombus, and enlargement of the right atrium and right ventricle?

• A. Aortic stenosis
• B. Mitral stenosis
• C. Mitral regurgitation
• D. Tricuspid stenosis

Answer: (B)

Mitral stenosis is the condition that fits this pattern. When the mitral valve is narrowed, blood struggle to move from the left atrium to the left ventricle during diastole, causing pressure to build up in the left atrium. That elevated pressure leads the left atrium to enlarge, and the sluggish flow can allow a thrombus to form in the left atrial appendage. The high left atrial pressure is then transmitted backward into the pulmonary circulation, raising pulmonary pressures. Over time this pulmonary hypertension increases the workload on the right heart, producing enlargement and possible hypertrophy of the right atrium and right ventricle. So the combination of left atrial enlargement with a potential thrombus and right-sided chamber enlargement is classic for mitral stenosis. Aortic stenosis mainly causes changes on the left ventricle from outflow obstruction, not the prominent left atrial thrombus pattern. Mitral regurgitation can cause left atrial enlargement as well, but the prominent secondary right-heart enlargement due to pulmonary hypertension is more characteristic of mitral stenosis. Tricuspid stenosis centers on the right heart and doesn’t typically produce the described left atrial thrombus scenario.

Mitral stenosis is the condition that fits this pattern. When the mitral valve is narrowed, blood struggle to move from the left atrium to the left ventricle during diastole, causing pressure to build up in the left atrium. That elevated pressure leads the left atrium to enlarge, and the sluggish flow can allow a thrombus to form in the left atrial appendage. The high left atrial pressure is then transmitted backward into the pulmonary circulation, raising pulmonary pressures. Over time this pulmonary hypertension increases the workload on the right heart, producing enlargement and possible hypertrophy of the right atrium and right ventricle. So the combination of left atrial enlargement with a potential thrombus and right-sided chamber enlargement is classic for mitral stenosis.

Aortic stenosis mainly causes changes on the left ventricle from outflow obstruction, not the prominent left atrial thrombus pattern. Mitral regurgitation can cause left atrial enlargement as well, but the prominent secondary right-heart enlargement due to pulmonary hypertension is more characteristic of mitral stenosis. Tricuspid stenosis centers on the right heart and doesn’t typically produce the described left atrial thrombus scenario.