Background: Cardiogenic shock is a deadly complication of an acute myocardial infarction (MI). We sought to characterize differences in patient features, treatments, and outcomes of cardiogenic shock by MI classification: ST-segment-elevation MI (STEMI) versus non-ST-segment elevation MI (NSTEMI).
Methods and results: We compared differences in care by the shock status of 235 541 patients with STEMI and NSTEMI treated at 392 US hospitals from 2007 to 2011. Cardiogenic shock occurred in 12.2% of patients with STEMI versus 4.3% of patients with NSTEMI. Compared with STEMI shock, NSTEMI shock was more likely in patients who were older and predominantly women; had diabetes mellitus, hypertension, previous heart failure, MI, or peripheral arterial disease; and who received coronary artery bypass grafting (11.6% versus 21.2%; P<0.0001) but less likely to have received percutaneous coronary intervention (84.2% versus 35.3%; P<0.0001). Compared with patients with STEMI presenting with shock at admission, patients with NSTEMI presenting with shock had longer delays to percutaneous coronary intervention (1.2 versus 3.2 hours) and coronary artery bypass grafting (7.9 versus 55.9 hours). Cardiogenic shock in patients with STEMI was associated with a lower mortality risk (33.1% shock versus 2.0% no shock; adjusted odds ratio, 14.1; 95% confidence interval, 13.0-15.4; interaction P value <0.0001) compared with patients with NSTEMI (40.8% shock versus 2.3% no shock, odds ratio, 19.0; 95% confidence interval, 17.1-21.2).
Conclusions: Cardiogenic shock is associated with high mortality in patients with STEMI and NSTEMI. However, urgent revascularization is more commonly pursued in patients with STEMI presenting with shock than in patients with NSTEMI. More research is needed to improve the outcomes for patients with MI presenting with shock, particularly those presenting with NSTEMI.
Keywords: myocardial infarction; outcome assessment; shock, cardiogenic.