A 40-year-old woman with rheumatic mitral stenosis reports difficulty swallowing solids. A barium swallow shows posterior indentation of the oesophagus below the level of the tracheal bifurcation. Which cardiac chamber accounts for this finding?
- A Right atrium
- B Left atrium ✓
- C Right ventricle
- D Left ventricle
Correct answer: B. Left atrium
Explanation
The left atrium is the most posterior chamber of the heart and lies directly anterior to the oesophagus. Enlargement in mitral stenosis compresses the oesophagus from in front, producing the posterior barium indentation seen on lateral views. The right atrium is the rightmost posterior chamber but does not contact the oesophagus, and the ventricles lie anteroinferiorly away from the oesophagus.
Reference: Gray's Anatomy for Students, 4th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.