Cardiogenic shock due to cardiac free-wall rupture or tamponade after acute myocardial infarction: A report from the SHOCK Trial Registry

OBJECTIVES We sought to compare the characteristics and outcomes of patient s with acute myocardial infarction (MI) and cardiogenic shock (CS) caused b y rupture of the ventricular free wall or tamponade versus shock from other causes. BACKGROUND Free-wall rupture is a recognized cause of mortality in patients with acute MI. Some of these patients present subacutely, which provides a n opportunity for intervention. Recognition of factors that distinguish the m from the overall shock cohort would be beneficial. METHODS The international SHOCK Trial Registry enrolled patients concurrent ly with the randomized SHOCK Trial. Thirty-six centers consecutively enroll ed all patients with suspected CS after MI, regardless of trial eligibility . RESULTS Of the 1,048 patients studied, 28 (2.7%) had free-wall rupture or t amponade. These patients had less pulmonary edema, less diabetes, less prio r MI, and less prior congestive heart failure (all p < 0.05). They more oft en had new Q waves in two or more leads (51.9% vs. 31.5%, p < 0.04), but MI location and time to shock onset after MI did not differ. Of patients with rupture or tamponade, 75% had pericardial effusions. No hemodynamic charac teristics identified patients with rupture/tamponade. Most patients with ru pture/tamponade had surgery and/or pericardiocentesis (27/28); their in-hos pital survival rate was identical to that of the group overall (39.3%). Wom en and older patients with rupture/tamponade tended to survive intervention less often. CONCLUSIONS Free-wall rupture and tamponade may present as CS after MI, and survival after intervention is similar to that of the overall shock cohort . AU patients with CS after MI should have echocardiography in order to det ect subacute rupture or tamponade and initiate appropriate interventions. ( J Am Coll Cardiol 2000;36:1117-22) (C) 2000 by the American College of Card iology.