Shock in the cardiac intensive care unit: Changes in epidemiology and prognosis over time

Background There are few studies documenting the changing epidemiology and outcomes of shock in cardiac intensive care unit (CICU) patients. We sought to describe the changes in shock epidemiology and outcomes over time in a CICU population. Methods We included 1859 unique patients admitted to the Mayo Clinic Rochester CICU from 2007 through 2018 with an admission diagnosis of shock. Temporal trends, including mortality, were assessed across 3-year periods. Results Shock comprised 15.1% of CICU admissions during the study period, increasing from 8.8% of CICU admissions in 2007 to 21.6% in 2018 (P .01 for trend). Mean age was 68 +/- 14 years (38% females). Shock was cardiogenic in 65%, septic in 10% and mixed cardiogenic-septic in 15%. Concomitant diagnoses in patients with cardiogenic shock (CS) included acute coronary syndrome (ACS) in 17%, heart failure (HF) in 35% and both in 40%. There was no significant change in the prevalence of individual shock subtypes over time (P .1). Among patients with CS, the prevalence of ACS decreased and the prevalence of HF increased over time (P < .01). Hospital mortality was highest among patients with mixed shock (39%; P = .05). Among patients with CS, hospital mortality was lower among those with HF compared to those without HF (31% vs. 40%, P < .01). Hospital mortality decreased over time among patients with shock (P < .01) and CS (P = .02). Conclusions The prevalence of shock in the CICU has increased over time, with a substantial prevalence of mixed CS. The etiology of CS has changed over the last decade with HF overtaking ACS as the most common cause of CS in the CICU.