Papillary muscle rupture after myocardial infarction typically occurs within how many days?

• A. Immediately during MI
• B. 2-7 days after STEMI/NSTEMI
• C. Months after MI
• D. Prior to MI

Answer: (B)

Timing of papillary muscle rupture after myocardial infarction reflects a mechanical complication that typically occurs in the subacute period when necrotic tissue is weakened by inflammatory cleanup. The rupture most often happens 2 to 7 days after the infarct (STEMI or NSTEMI). This timing leads to abrupt, severe mitral regurgitation with sudden congestion, pulmonary edema, and possible shock. Rupture during the infarct is unlikely because the tissue needs time to necrose and then be degraded by macrophages; months after an MI would suggest chronic scar-related dysfunction rather than an acute rupture, and prior to an MI is not possible.