Epidemiology and causes of cardiogenic shock.

PURPOSE OF REVIEW: Cardiogenic shock is a complex clinical syndrome of end-organ hypoperfusion due to impaired cardiac performance. Although cardiogenic shock has traditionally been viewed as a monolithic disorder predominantly caused by severe left ventricular dysfunction complicating acute myocardial infarction (AMI), there is increasing recognition of the diverse causes of cardiogenic shock and wide spectrum of clinical severity. The purpose of this review is to describe the contemporary epidemiology of cardiogenic shock, including trends in clinical outcomes and recent efforts to refine risk assessment.

RECENT FINDINGS: The incidence of cardiogenic shock among patients with AMI has remained remarkably stable at 3-10%; however, the proportion of cardiogenic shock cases related to AMI has decreased over time to ∼30%, while the proportion of cardiogenic shock cases due to acute decompensated heart failure has steadily increased. Estimated in-hospital mortality from cardiogenic shock in contemporary registries is approximately 30-40%, suggesting modest improvement in cardiogenic shock outcomes over the last decade. There is a wide spectrum of clinical severity among patients presenting with cardiogenic shock, which is described by the Society for Cardiovascular Angiography and Interventions clinical staging criteria.

SUMMARY: Improved clinical characterization and risk assessment of patients with cardiogenic shock may facilitate more effective clinical investigations of this morbid clinical syndrome.