During repair of a ventricular septal defect, a fibromuscular band is seen crossing the cavity of the right ventricle from the interventricular septum to the base of the anterior papillary muscle. Which structure does this band carry?
- A Right bundle branch of the conducting system ✓
- B Left anterior descending coronary artery
- C Anterior papillary muscle tendon
- D Middle cardiac vein
Correct answer: A. Right bundle branch of the conducting system
Explanation
The septomarginal trabecula, or moderator band, stretches from the interventricular septum to the base of the anterior papillary muscle in the right ventricle and carries the right bundle branch of the conduction system. This route allows rapid activation of the anterior papillary muscle. It contains no arterial or venous structures, so options B and D are anatomically impossible, and option C confuses the destination of the band with its content.
Reference: Gray's Anatomy for Students, 4th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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