A 68-year-old man presents with dysphagia due to enlargement of which structure is the most likely cause of his swallowing difficulty?

• A. Left atrium
• B. Left ventricle
• C. Right atrium
• D. Right ventricle

Answer: (A)

The enlargement of the left atrium can lead to dysphagia due to its anatomical proximity to the esophagus. In particular, an enlarged left atrium can exert pressure on the esophagus as it traverses the mediastinum, leading to swallowing difficulties. This condition is often associated with underlying cardiac disorders, such as mitral valve disease or hypertension, which can result in left atrial enlargement.

As the left atrium dilates, it can physically compress the esophagus, which runs adjacent to it, producing symptoms of dysphagia. This is particularly common in older adults or in patients with chronic cardiac conditions. The other cardiac chambers, such as the left ventricle, right atrium, and right ventricle, do not typically have the same direct impact on the esophagus due to their locations within the thoracic cavity. Therefore, the left atrium stands out as the most likely structure responsible for the dysphagia in this scenario.