Recent magnitude of and temporal trends (1994-1997) in the incidence and hospital death rates of cardiogenic shock complicating acute myocardial infarction: The second National Registry of Myocardial Infarction

Background Limited recent data are available to describe the magnitude of, and temporal trends in, the incidence and case-fatality rates associated wi th cardiogenic shock complicating acute myocardial infarction. The purpose of this study was to examine recent (1994-1997) trends in the incidence of, and hospital death rates From, cardiogenic shock complicating acute myocar dial infarction from a large, multihospital national perspective. Methods An observational study was performed of 426,253 patients hospitaliz ed with acute myocardial infarction in 1662 hospitals throughout the United States between 1994 and 1997. Results The incidence rates of cardiogenic s hock averaged 6.2%. There was evidence for a slight decline in these rates between 1994 (6.6%) and 1997 (6.0%). Results of a multivariable regression analysis controlling for factors that might affect the risk of development of cardiogenic shock indicated that p atients hospitalized in more recent years were at significantly lower risk for shock. Patients with shock had a markedly increased risk for dying duri ng hospitalization compared with patients not having shock (74% vs 10%). Si gnificant, albeit small, absolute differences were observed in the risk of dying after cardiogenic shock over time (76% dying in 1997 72% dying in 199 4). These improving trends were magnified, however, after potentially confo unding prognostic factors were controlled: patients having shock in 1997 we re at approximately one fifth lower risk of dying (odds ratio 0.79, 95% con fidence interval 0.71-0.87) than those hospitalized in 1994. Conclusions Our findings indicate a slight decline in the incidence rates o f cardiogenic shock and improving trends in the hospital survival of patien ts with shock. Despite these trends, it remains of considerable importance to prevent this clinical syndrome, given its high lethality.