#EMconf: Acute SOB

Diagnosis: Papillary Muscle Rupture

Mechanical Complications of MI:
-Ventricular septal defect 
-LV free wall rupture (usually rapidly lethal) 
-Papillary muscle rupture leading to acute mitral regurgitation and acute pulmonary edema


Papillary Muscle Rupture
-Two papillary muscles, anterior (lateral) and posterior (medial)
-Posterior muscle ruptures more often since sole blood supply from the RCA or L Circ
-Anterior muscle has dual blood supply from LAD and L Circ
-With MI, may have necrosis of papillary muscle and then sudden rupture resulting in severe mitral regurgitation

-Timing: Usually happens a few days after MI (rarely > 14 days post MI)
-Presentation: Patient uniformly presents in heart failure, with up to 60% in cardiogenic shock
-Diagnosis: Transthoracic echo usually adequate but may need transesophageal
-Treatment: – CT surgery emergently; intra-aortic balloon pump may help hemodynamics prior to surgery 


Transthoracic echo demonstrating the papillary muscule rupture:




Transesophageal echo of the same patient with color Doppler: