Admission Society for Cardiovascular Angiography and Intervention shock stage stratifies post-discharge mortality risk in cardiac intensive care unit patients

Background: The five-stage Society for Cardiovascular Angiography and Intervention (SCAI) cardiogenic shock classification scheme can stratify hospital mortality risk in patients admitted to the cardiac intensive care unit (CICU). We sought to evaluate the SCAI shock classification for prediction of post-discharge mortality in CICU survivors. Methods: We retrospectively analyzed hospital survivors admitted to a single CICU between 2007 and 2015. SCAI CS stages A through E were classified using CICU admission data using a previously published algorithm. All-cause post-discharge mortality was compared across SCAI stages using Kaplan-Meier analysis and Cox proportional hazards models. Results: Among 9096 unique hospital survivors, 43.2% had acute coronary syndrome (ACS), 44.6% had heart failure (HF), and 8.7% had cardiac arrest (CA) on admission. The proportion of patients in each SCAI shock stage was: A, 49.1%; B, 30.6%; C, 15.2; D/E 5.2%. Kaplan-Meier survival at 5 years in each SCAI shock stage was: A, 88.2%; B, 81.6%; C, 76.7%; D/E, 71.7% (P <.001 by log-rank). Each higher SCAI shock stage was associated with increased adjusted post-discharge mortality compared to SCAI shock stage A (all P <.001); results were consistent among patients with ACS or HF. Late hemodynamic deterioration after 24 hours, but not an admission diagnosis of CA, was associated with higher post-discharge mortality. Conclusions: The SCAI shock classification assessed at the time of CICU admission was predictive of post-discharge mortality risk among hospital survivors, although an admission diagnosis of CA was not. The SCAI shock classification can be used for post-discharge mortality risk stratification.