A 65-year-old man develops sudden hypotension and new pansystolic murmur loudest at the apex 5 days after an inferior STEMI managed with primary PCI. An echocardiogram shows severe mitral regurgitation with rupture of the posteromedial papillary muscle. The MOST appropriate immediate management is:
- A Intra-aortic balloon pump bridging to emergency mitral valve surgery ✓
- B Intra-aortic balloon pump (IABP) insertion alone
- C IV sodium nitroprusside to reduce afterload
- D MitraClip transcatheter repair as definitive treatment
Explanation
Papillary muscle rupture causing severe acute MR is a mechanical complication of STEMI with extremely high mortality (>50% at 24 hours without surgery). IABP reduces afterload and improves haemodynamics as a bridge to emergency mitral valve surgery (repair or replacement), which remains the definitive treatment. Nitroprusside alone provides haemodynamic relief but does not address the structural lesion. MitraClip is not approved for acute severe MR due to papillary rupture in cardiogenic shock. The posteromedial papillary muscle is more vulnerable because it has a single blood supply (PDA from RCA, affected in inferior MI).
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.