Prognostic validation and risk stratification of the Society for Cardiovascular Angiography and Interventions cardiogenic shock classification in a large, real-world intensive care unit cohort in South Korea.

BACKGROUND

Cardiogenic shock (CS) imparts a high mortality rate, yet a standardized classification of its severity remains lacking. The Society for Cardiovascular Angiography and Interventions (SCAI) proposed a five-stage classification scheme to improve risk stratification, but its prognostic value in real-world intensive care unit (ICU) populations is still insufficiently validated.

METHODS

We retrospectively analyzed 3,074 adults admitted to the medical and cardiovascular ICUs under the Division of Cardiology at a tertiary academic medical center between 2010 and 2019. SCAI shock stages (A-E) were assigned at admission using data on hemodynamic instability, hypoperfusion, clinical deterioration, and refractory shock. The primary outcome was ICU mortality.

RESULTS

ICU mortality rates across stages A-E were 0.5%, 4.3%, 5.2%, 18.8%, and 53.2% (P<0.001). Compared to stage A, higher stages were independently associated with mortality (adjusted odds ratio, 3.93-31.58). The discriminatory ability of the SCAI CS classification was moderate (area under the receiver operating characteristic curve [AUROC], 0.787) but improved markedly with the addition of Acute Physiology and Chronic Health Evaluation II scores (AUROC, 0.929).

CONCLUSIONS

The SCAI CS classification offers clear, incremental risk stratification of ICU mortality. When combined with global severity scores, it provides superior prognostic accuracy, supporting its routine use in the management and study of CS.