Skip Navigation
Skip to contents

ACC : Acute and Critical Care

OPEN ACCESS
SEARCH
Search
Advanced Search
mobile menu button

Articles

Page Path
HOME > Acute Crit Care > Volume 41(1); 2026 > Article
Original Article
Cardiology 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
Acute and Critical Care 2026;41(1):117-125.
DOI: https://doi.org/10.4266/acc.004500
Published online: February 27, 2026

1Division of Cardiology, Department of Internal Medicine, SMG-SNU Boramae Medical Center, Seoul, Korea

2Department of Critical Care Medicine, SMG-SNU Boramae Medical Center, Seoul, Korea

3Division of Cardiology, Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea

4Department of Critical Care Medicine, Seoul National University Hospital, Seoul, Korea

Corresponding author: Jeehoon Kang Division of Cardiology, Department of Internal Medicine and Department of Critical Care Medicine, Seoul National University Hospital, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul 03080, Korea Tel: +82-2-2072-1181 Email: medikang@snu.ac.kr
• Received: October 1, 2025   • Revised: December 7, 2025   • Accepted: December 18, 2025

© 2026 The Korean Society of Critical Care Medicine

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

  • 464 Views
  • 24 Download
prev next
Full Article

Download PDF Download PDF

  • 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.
  • Key Words: cardiogenic shock; intensive care units; risk assessment
Cardiogenic shock (CS) remains a major clinical challenge, with high morbidity and mortality rates despite advances in therapy [1-3]. Although diagnostic criteria are well established, there is still no universal system to classify severity, leading to considerable heterogeneity across studies and in clinical practice [4]. Existing mortality risk scores are often tailored to acute myocardial infarction (MI)-related CS and require multiple clinical and laboratory variables, making it difficult to apply them broadly at the bedside. These limitations highlight the need for a simpler and more practical tool that can be used across diverse settings to improve communication and guide treatment decisions [5,6].
The five-stage CS classification scheme recently proposed by the Society for Cardiovascular Angiography and Interventions (SCAI) addresses these challenges by introducing a structured system for assessing CS severity [7]. This classification categorizes patients into progressive stages of hemodynamic compromise and includes a modifier for cardiac arrest, enabling more effective clinical decision-making and research standardization. While this system holds promise for improving clinical outcomes and facilitating trial designs, its ability to predict mortality risk across diverse patient populations remains insufficiently validated.
In this study, we sought to validate the prognostic performance of the SCAI CS classification in a large intensive care unit (ICU) cohort. We also examined whether combining SCAI staging with global severity scores, such as Acute Physiology and Chronic Health Evaluation (APACHE) II, could further enhance predictive accuracy. By addressing these questions, we aim to clarify the role of the SCAI system as a reliable tool for risk stratification and clinical decision-making in CS.
The study was performed according to the Declaration of Helsinki and was approved by the Institutional Review Board of Seoul National University Hospital (No. 2303-160-1416). The requirement for informed consent was waived because the study used de-identified data extracted from the institutional clinical data warehouse, posing minimal risk to patients.
Study Population
The study population included adults (≥18 years old) admitted to the medical ICU (MICU) and cardiovascular care unit of a tertiary academic medical center between January 1, 2010, and December 31, 2019. In the MICU, only patients admitted under the Division of Cardiology were included to ensure the capture of CS cases. To minimize bias from multiple admissions, only the first ICU admission per patient during the study period was analyzed (Figure 1).
Data Source
Demographic, clinical, and laboratory data, as well as treatment and outcome information, were extracted from the institutional clinical data warehouse. Admission values of vital signs, laboratory parameters, and clinical measurements were defined as the first recorded values after ICU admission. The vasoactive–inotropic score and norepinephrine-equivalent vasopressor dose were calculated using peak medication doses during the ICU stay [8]. The APACHE II score was automatically calculated using data from the first 24 hours of ICU admission [9,10]. Admission diagnoses were determined using the International Classification of Diseases, Tenth Revision.
Definition of Shock Stages
SCAI CS stages (A–E) were assigned using a predefined, rule-based algorithm based on clinical, hemodynamic, and laboratory variables available from the first 24 hours of ICU admission. Each staging component, such as hypotension, hypoperfusion, clinical deterioration, and refractory shock, was mapped directly to structured medical record fields obtained from the institutional clinical data warehouse. Detailed operational definitions and thresholds used for stage assignment are provided in Supplementary Tables 1 and 2 [7,11].
Study Outcomes
The primary outcome was all-cause ICU mortality. Secondary outcomes included 60-day mortality and the need for advanced ICU therapies, such as an intra-aortic balloon pump, extracorporeal membrane oxygenation (ECMO), vasopressors/inotropes, or continuous renal replacement therapy (CRRT), during the ICU stay.
Statistical Analysis
Categorical variables are reported as counts and percentages and were compared using Pearson’s chi-square test. Continuous variables are expressed as mean±standard deviation values. Trends across SCAI stages were assessed using linear regression for continuous variables and the chi-square test for categorical variables. Logistic regression was used to examine the association between SCAI stages and ICU mortality, adjusting for age, sex, admission diagnosis, and APACHE II scoring. Discriminatory ability was evaluated using the area under the receiver operating characteristic curve (AUROC). A two-tailed P-value of <0.05 was considered statistically significant. All analyses were performed using R version 4.0.3 (R Foundation for Statistical Computing).
A total of 3,074 patients were classified as follows into the five SCAI stages at ICU admission: stage A (n=858, 27.9%), stage B (n=328, 10.7%), stage C (n=1,490, 48.5%), stage D (n=304, 9.9%), and stage E (n=94, 3.1%). Baseline characteristics are summarized in Table 1. The mean age was 68 years, and 31.2% of study participants were admitted with MI. Cardiac arrest occurred in 3.9% of participants, with a greater frequency of such occurring in advanced stages. Admission vital signs differed significantly across stages (P<0.001). Severity scores and laboratory findings worsened progressively: APACHE II scores rose with stage advancement, from 12.2±6.1 points in stage A to 32.6±12.8 points in stage E. Lactate, creatinine, and blood urea nitrogen values were also higher with worse SCAI stages, whereas bicarbonate and arterial pH values were lower. Of note, however, the maximum lactate concentration within 24 hours was higher with worse staging, from 1.63±1.08 mmol/L in stage A to 11.25±7.05 mmol/L in Stage E.
Mortality and Survival Outcomes
ICU mortality increased stepwise, from 0.5% in stage A to 53.2% in stage E (P<0.001) (Figure 2). Kaplan–Meier curves showed progressively lower 30-day survival across stages (log-rank P<0.001) (Figure 3). The 60-day mortality rate also rose with advancements in staging (log-rank P<0.001) (Figure 4).
Use of Advanced Therapies
The need for advanced therapies escalated with stage severity (Table 2). ECMO was used in 0.8% of stage A and 34.0% of stage E patients, respectively (P<0.001), and CRRT use increased from 2.6% to 46.8% and mechanical ventilation increased from 11.9% to 71.3% between stages A and E. Use of an intra-aortic balloon pump and coronary angiography also rose across stages, whereas percutaneous coronary intervention rates remained stable (P=0.060).
Multivariable Analysis and Discrimination
After adjustment for age, sex, admission diagnosis, and APACHE II scores, higher SCAI stages were independently associated with ICU mortality. Adjusted odds ratios (vs. stage A) were as follows: stage B, 3.93 (95% CI, 1.05–14.76; P=0.043); stage C, 8.59 (95% CI, 2.61–28.32; P<0.001); stage D, 10.71 (95% CI, 3.18–36.06; P<0.001); and stage E, 31.58 (95% CI, 8.63–115.53; P<0.001). The SCAI CS classification alone showed moderate discrimination (AUROC, 0.787; 95% CI, 0.756–0.819), while adding APACHE II scores significantly improved performance (AUROC, 0.929; 95% CI, 0.911–0.944; P<0.001) (Figure 5). AUROC values for the SCAI classification alone, APACHE II score alone, their combination, and individual physiological markers (initial lactate concentration and 24-hour vasoactive–inotropic score) are summarized in Supplementary Table 3.
In this large, real-world ICU cohort, we validated the SCAI CS classification as a clinically meaningful framework for risk stratification and prognostic assessment. Among 3,074 patients admitted to the study MICU and CCU, increasing SCAI stages were strongly and progressively associated with higher ICU mortality and the need for advanced organ support. These findings reinforce the clinical relevance of the SCAI CS classification and support its incorporation into contemporary shock-management algorithms [7,12,13].
CS represents a complex and dire hemodynamic state defined by the heart's profound inability to generate sufficient cardiac output to meet systemic metabolic demands, leading to widespread tissue hypoperfusion and hypoxia [14]. The foundational pathophysiology is a self-perpetuating cycle initiated by a primary insult—most commonly extensive MI affecting a critical mass of the left ventricular myocardium [15,16]. This initial loss of contractility leads to a rapid reduction in stroke volume and, consequently, decreased cardiac output. The body's neurohormonal response, primarily through sympathetic activation, attempts to compensate for this by increasing the heart rate and systemic vascular resistance [17]. However, while these mechanisms transiently support blood pressure, they are ultimately detrimental. The increased afterload and heart rate amplify myocardial oxygen demand, exacerbating existing ischemia within the compromised myocardium [18]. This further depresses contractility, solidifying the cycle of hemodynamic collapse, which, if left unchecked, culminates in multisystem organ failure [4,19].
To facilitate a more systematic standardized framework for risk stratification and communication, the SCAI CS classification system was proposed [7]. By providing a rapid, real-time bedside assessment of patients across five stages, this scheme has a robust prognostic and predictive value. This risk stratification guides critical clinical decision-making, including regarding the need for and timing of mechanical circulatory support and transfer to specialized care centers [7,20,21].
From our results, the overall mortality of CS was 6.6% (n=203/3,074), which underscores the severity of CS and is consistent with findings of previous studies. However, due to the heterogeneity of the study population, clinicians need to have a clear risk stratification for these patients [20]. Our results demonstrated a clear stepwise increase in ICU mortality across SCAI stages, ranging from 0.5% in stage A to 53.2% in stage E, accompanied by progressively lower overall survival. In-hospital mortality showed a similar overall pattern (Figure 4, Supplementary Figure 1). These findings are consistent with findings of previous studies conducted in North American cohorts [7], but our study extends this evidence to a broader, unselected ICU population, including those with non–acute MI causes of CS. In subgroup analysis stratified by MI status, the prognostic gradient of the SCAI classification was preserved consistently (Supplementary Figure 2): specifically, we found that ICU mortality increased progressively from stage A to stage E in both MI and non-MI patients, supporting the applicability of the SCAI framework across major etiologic subgroups.
The discriminatory ability of the SCAI CS classification alone for ICU mortality was moderate (AUROC, 0.787), consistent with prior validation studies [22,23]. This concordance reinforces the robustness and reproducibility of the classification, even in our heterogeneous ICU population. In contrast, traditional severity indices such as the APACHE II score have shown limited prognostic accuracy in CS, reflecting their lack of specificity for hemodynamic collapse [24,25]. Importantly, when the SCAI CS classification was combined with APACHE II scores, the overall model performance improved substantially (AUROC, 0.929), underscoring the incremental prognostic value of integrating a shock-specific staging system with a global severity score. Together, these findings support the role of SCAI staging not only as an independent predictor but also as a complementary tool that enhances established ICU risk models. Notably, the combination of SCAI and APACHE II demonstrated a narrow 95% CI (0.911–0.944) for its AUROC, and SCAI CS classification remained independently associated with ICU mortality after adjustment for APACHE II scoring, supporting the stability of this combined approach. Given that both SCAI CS classification and APACHE II are established scoring systems, the improved discrimination likely reflects complementary physiologic information rather than model overfitting.
We also observed a significant gradient in the use of advanced therapies across stages. ECMO was initiated in more than one-third of stage E patients, while CRRT and mechanical ventilation were used in nearly half and 71.3% of these patients, respectively. These findings align with prior work emphasizing the role of early mechanical circulatory support and organ-replacement therapies in advanced shock [4,26,27]. However, the rate of percutaneous coronary intervention did not differ significantly across stages (P=0.060), suggesting that revascularization decisions may depend on additional clinical factors beyond shock severity alone. Our findings also highlight the real-world implications of SCAI staging for ICU resource planning and decision-making. As CS continues to pose significant clinical and logistical challenges, the implementation of standardized staging systems has the potential to guide triage, facilitate multidisciplinary team communication, and support timely deployment of therapies such as ECMO and Impella (Abiomed) [27,28].
This study has several strengths, including a large sample size, structured ICU data spanning a decade, and consistent classification across a clinically meaningful staging framework. Nonetheless, it is not without limitations. First, SCAI stages were assigned retrospectively using simplified operational definitions adapted from the original consensus document, which may introduce potential misclassification bias. However, all stage assignments were performed using a predefined, rule-based algorithm, ensuring high reproducibility across the cohort. The degree of missingness for key physiologic variables used in stage assignment is provided in Supplementary Table 4. Second, we did not perform serial stage reassessment, which may offer additional prognostic information. Future prospective studies with structured and time-specific physiologic assessments are needed to determine whether serial reassessment of the SCAI stage provides incremental prognostic value beyond baseline staging. Third, microcirculatory and metabolic markers, which may provide additional physiologic resolution beyond the macrocirculatory parameters captured by the SCAI classification, were not available in our clinical data warehouse and therefore could not be evaluated. Finally, as a single-center study conducted in a high-resource tertiary setting, generalizability to other institutions may be limited.
In conclusion, the SCAI CS classification demonstrated robust prognostic discrimination, physiologic coherence, and clinical applicability in a diverse ICU population. Our findings support its integration into critical care workflows, prospective registries, and clinical trials design to improve the care of patients with CS.
▪ The Society for Cardiovascular Angiography and Interventions (SCAI) cardiogenic shock classification demonstrates clear, stepwise prognostic discrimination across a large, real-world intensive care unit (ICU) cohort, with ICU mortality rates ranging from 0.5% (stage A) to 53.2% (stage E).
▪ Combining SCAI staging with global severity scores such as Acute Physiology and Chronic Health Evaluation II substantially improves predictive accuracy (area under the receiver operating characteristic curve, 0.787–0.929), underscoring its complementary prognostic utility.
▪ SCAI staging facilitates clinical decision-making and ICU resource allocation by identifying patients most likely to require advanced therapies, including extracorporeal membrane oxygenation, continuous renal replacement therapy, and mechanical ventilation.

CONFLICT OF INTEREST

Jeehoon Kang is an editorial board member of the journal but was not involved in the peer reviewer selection, evaluation, or decision process of this article. No other potential conflict of interest relevant to this article was reported.

FUNDING

None.

ACKNOWLEDGMENTS

None.

AUTHOR CONTRIBUTIONS

Conceptualization: JK, HJC. Data curation: HC. Formal analysis: HC, MH. Methodology: JK, HC, HJC. Visualization: HL, MH. Project administration: JK, HJC. Writing – original draft: HC, JK. Writing – review & editing: HL, MH, HJC. All authors read and agreed to the published version of the manuscript.

Supplementary materials can be found via https://doi.org/10.4266/acc.004500.
Supplementary Table 1.
Study definitions of hypotension, tachycardia, hypoperfusion, deterioration, and refractory shock
acc-004500-Supplementary-Table-1.pdf
Supplementary Table 2.
Definition of CS stages used in this study, based on the SCAI consensus statement classification
acc-004500-Supplementary-Table-2.pdf
Supplementary Table 3.
Discriminative performance of individual markers and scoring systems for ICU mortality
acc-004500-Supplementary-Table-3.pdf
Supplementary Table 4.
The number of missing values and the missing rate for each variable (n=3,074)
acc-004500-Supplementary-Table-4.pdf
Supplementary Figure 1.
Intensive care unit (ICU) mortality and in-hospital mortality across Society for Cardiovascular Angiography and Interventions (SCAI) cardiogenic shock stages.
Bar chart showing ICU and in-hospital mortality across SCAI cardiogenic shock stages (A through E). Both outcomes demonstrated an overall increasing trend with advancing SCAI stage, illustrating the progressive worsening of prognosis with higher shock severity.
acc-004500-Supplementary-Figure-1.pdf
Supplementary Figure 2.
Intensive care unit (ICU) mortality across Society for Cardiovascular Angiography and Interventions (SCAI) cardiogenic shock stages in myocardial infarction (MI) and non-MI patients. Bar chart showing ICU mortality across SCAI cardiogenic shock stages (A through E) stratified by MI status. A progressive increase in mortality was observed with advancing SCAI stage in both MI and non-MI subgroups, indicating that the prognostic gradient of the SCAI classification is preserved irrespective of underlying MI etiology.
acc-004500-Supplementary-Figure-2.pdf
Figure 1.
Flowchart of study population selection. The flowchart illustrates the process of selecting the study cohort. Among 24,752 cardiology patients admitted to the medical intensive care unit (MICU) or cardiovascular care unit (CCU) during the study period, those admitted for simple monitoring or same-day procedures were excluded. After excluding readmissions, 3,074 patients were included in the final analysis and classified according to Society for Cardiovascular Angiography and Interventions cardiogenic shock stage.
acc-004500f1.jpg
Figure 2.
Intensive care unit (ICU) mortality by Society for Cardiovascular Angiography and Interventions (SCAI) cardiogenic shock (CS) stage. ICU mortality increased stepwise with higher SCAI staging, rising from 0.5% in stage A to 53.2% in stage E (P<0.001).
acc-004500f2.jpg
Figure 3.
Kaplan-Meier curves for 30-day intensive care unit survival according to Society for Cardiovascular Angiography and Interventions (SCAI) stage. Analysis revealed that 30-day survival declined progressively with SCAI stage increase (log-rank P<0.001), demonstrating the classification’s prognostic discrimination.
acc-004500f3.jpg
Figure 4.
Kaplan-Meier curves for 60-day in-hospital survival according to Society for Cardiovascular Angiography and Interventions (SCAI) stage. Analysis revealed that 60-day survival was significantly lower with advanced SCAI staging (log-rank P<0.001), indicating sustained prognostic separation.
acc-004500f4.jpg
Figure 5.
Receiver operating characteristic curves for intensive care unit (ICU) mortality prediction. Receiver operating characteristic curves comparing the predictive performance of the Cardiovascular Angiography and Interventions (SCAI) cardiogenic shock (CS) classification, Acute Physiology and Chronic Health Evaluation (APACHE) II score, and the combination of both for ICU mortality. The area under the receiver operating characteristic curve values were 0.787 (95% CI, 0.756–0.819) for the SCAI classification, 0.909 (95% CI, 0.888–0.930) for APACHE II, and 0.927 (95% CI, 0.911–0.944) for the combined model. a) The combined model demonstrated significantly higher discriminative performance than the SCAI CS classification alone (P<0.001), indicating the complementary prognostic value of integrating APACHE II with the SCAI CS classification.
acc-004500f5.jpg
Table 1.
Baseline characteristics
Variable Stage A (n=858) Stage B (n=328) Stage C (n=1,490) Stage D (n=304) Stage E (n=94) P-value
Demographics
 Age (yr) 71±13 69±14 67±15 69±14 68±14 <0.001
 Female 359 (41.8) 139 (42.4) 577 (38.7) 119 (39.1) 40 (42.6) 0.508
 BMI (kg/m2) 23.54±3.86 22.69±4.23 23.01±3.99 22.88±3.54 24.40±4.87 0.001
Admission ICD-10 diagnosis
 Myocardial infarction 313 (38.6) 85 (27.2) 432 (30.4) 100 (35.2) 29 (31.5) <0.001
 Heart failure 114 (14.4) 70 (23.0) 162 (11.4) 35 (12.2) 10 (10.9) <0.001
 Cardiac arrest 24 (2.8) 14 (4.3) 47 (3.2) 22 (7.2) 12 (12.8) <0.001
 Atrial fibrillation 58 (6.8) 47 (14.3) 132 (8.9) 19 (6.3) 10 (10.6) 0.001
 Ventricular tachycardia/fibrillation 19 (2.2) 8 (2.4) 47 (3.2) 7 (2.3) 1 (1.1) 0.528
APACHE II score 12.18±6.09 17.36±8.69 14.96±10.99 23.24±11.58 32.55±12.75 <0.001
 Admission vital signs
  Systolic blood pressure (mm Hg) 126.43±38.79 102.86±41.27 113.52±49.53 94.92±50.00 61.84±52.39 <0.001
  Diastolic blood pressure (mm Hg) 68.65±20.66 63.83±23.75 65.19±25.78 56.82±27.98 38.82±32.74 <0.001
  Mean blood pressure (mm Hg) 87.95±25.06 76.96±28.59 81.30±32.62 69.59±34.68 46.65±37.62 <0.001
  Heart rate (beats/min) 77.68±62.07 102.10±36.51 77.96±36.24 84.50±45.82 62.56±55.83 <0.001
  Respiratory rate (breaths/min) 30.62±19.05 31.52±17.94 25.36±16.65 26.65±17.59 19.91±20.14 <0.001
  Urine output first 24 hours (L) 1.86±9.19 1.93±9.73 4.11±7.83 9.54±1.75 1.08±1.82 <0.001
 Admission laboratory data
  Maximum lactate first 24 hours (mmol/L) 1.63±1.08 2.82±2.52 5.06±4.70 7.21±5.48 11.25±7.05 <0.001
  Creatinine (mg/dl) 1.10±0.72 1.15±0.61 1.56±1.92 2.38±2.51 1.99±2.03 <0.001
  BUN (mg/dl) 20.35±13.00 23.91±16.06 21.74±15.43 32.29±23.94 32.13±20.89 <0.001
  ALT (U/L) 43.60±107.58 90.66±276.37 86.30±387.42 177.60±549.85 395.63±836.62 <0.001
  AST (U/L) 57.77±120.45 127.68±438.45 113.48±549.86 299.89±953.19 698.60±1544.44 <0.001
  Peak troponin-I first 24 hours (ng/ml) 8.81±30.18 8.17±31.20 6.12±21.36 7.81±15.97 16.57±68.13 0.247
  Hemoglobin (g/dl) 12.10±2.06 11.69±2.16 12.14±2.21 11.63±2.46 11.62±2.50 0.001
  Arterial pH 7.41±0.07 7.39±0.10 7.39±0.11 7.37±0.13 7.27±0.18 <0.001
  Bicarbonate (mEq/L) 24.01±3.77 22.75±4.72 22.38±4.65 20.68±4.90 17.87±7.83 <0.001

Values are presented as number (%). The P-value is for the trend across SCAI cardiogenic shock stages A to E.

BMI: body mass index; ICD-10: International Classification of Diseases, Tenth Revision; APACHE: Acute Physiology and Chronic Health Evaluation; BUN: blood urea nitrogen; ALT: alanine aminotransferase; AST: aspartate aminotransferase; SCAI: Society for Cardiovascular Angiography and Interventions.

Table 2.
Use of advanced therapies and procedures during the ICU stay according to SCAI cardiogenic shock stage
Advanced therapies and procedures Stage A (n=858) Stage B (n=328) Stage C (n=1,490) Stage D (n=304) Stage E (n=94) P-value
IABP 26 (3.4) 35 (14.6) 49 (3.8) 41 (30.1) 15 (42.9) <0.001
ECMO 7 (0.8) 14 (4.3) 34 (2.3) 39 (12.8) 32 (34.0) <0.001
CRRT 22 (2.6) 20 (6.1) 82 (5.5) 97 (31.9) 44 (46.8) <0.001
Mechanical ventilation 102 (11.9) 90 (27.4) 201 (13.5) 166 (54.6) 67 (71.3) <0.001
Invasive coronary angiography 447 (52.1) 140 (42.7) 825 (55.4) 166 (54.6) 57 (60.6) <0.001
Percutaneous coronary intervention 315 (36.7) 95 (29.0) 544 (36.5) 120 (39.5) 33 (35.1) 0.060

Values are number (%). The P-value is for the trend across SCAI cardiogenic shock stages A to E.

ICU: intensive care unit; SCAI: Society for Cardiovascular Angiography and Interventions; IABP: intra-aortic balloon pump; ECMO: extracorporeal membrane oxygenation; CRRT: continuous renal replacement therapy.

  • 1. Kolte D, Khera S, Aronow WS, Mujib M, Palaniswamy C, Sule S, et al. Trends in incidence, management, and outcomes of cardiogenic shock complicating ST-elevation myocardial infarction in the United States. J Am Heart Assoc 2014;3:e000590. ArticlePubMedPMC
  • 2. Hunziker L, Radovanovic D, Jeger R, Pedrazzini G, Cuculi F, Urban P, et al. Twenty-year trends in the incidence and outcome of cardiogenic shock in AMIS Plus registry. Circ Cardiovasc Interv 2019;12:e007293. ArticlePubMed
  • 3. Berg DD, Bohula EA, van Diepen S, Katz JN, Alviar CL, Baird-Zars VM, et al. Epidemiology of shock in contemporary cardiac intensive care units. Circ Cardiovasc Qual Outcomes 2019;12:e005618. ArticlePubMedPMC
  • 4. van Diepen S, Katz JN, Albert NM, Henry TD, Jacobs AK, Kapur NK, et al. Contemporary management of cardiogenic shock: a scientific statement from the American Heart Association. Circulation 2017;136:e232-68.ArticlePubMed
  • 5. Harjola VP, Lassus J, Sionis A, Køber L, Tarvasmäki T, Spinar J, et al. Clinical picture and risk prediction of short-term mortality in cardiogenic shock. Eur J Heart Fail 2015;17:501-9.ArticlePubMedPDF
  • 6. Pöss J, Köster J, Fuernau G, Eitel I, de Waha S, Ouarrak T, et al. Risk stratification for patients in cardiogenic shock after acute myocardial infarction. J Am Coll Cardiol 2017;69:1913-20.Article
  • 7. Jentzer JC, van Diepen S, Barsness GW, Henry TD, Menon V, Rihal CS, et al. Cardiogenic shock classification to predict mortality in the cardiac intensive care unit. J Am Coll Cardiol 2019;74:2117-28.ArticlePubMed
  • 8. Jentzer JC, Wiley B, Bennett C, Murphree DH, Keegan MT, Kashani KB, et al. Temporal trends and clinical outcomes associated with vasopressor and inotrope use in the cardiac intensive care unit. Shock 2020;53:452-9.ArticlePubMed
  • 9. Knaus WA, Draper EA, Wagner DP, Zimmerman JE. Apache II: a severity of disease classification system. Crit Care Med 1985;13:818-29.ArticlePubMed
  • 10. Capuzzo M, Valpondi V, Sgarbi A, Bortolazzi S, Pavoni V, Gilli G, et al. Validation of severity scoring systems SAPS II and APACHE II in a single-center population. Intensive Care Med 2000;26:1779-85.ArticlePubMedPDF
  • 11. Baran DA, Grines CL, Bailey S, Burkhoff D, Hall SA, Henry TD, et al. SCAI clinical expert consensus statement on the classification of cardiogenic shock: this document was endorsed by the American College of Cardiology (ACC), the American Heart Association (AHA), the Society of Critical Care Medicine (SCCM), and the Society of Thoracic Surgeons (STS) in April 2019. Catheter Cardiovasc Interv 2019;94:29-37.ArticlePubMed
  • 12. Hanson ID, Tagami T, Mando R, Kara Balla A, Dixon SR, Timmis S, et al. Scai shock classification in acute myocardial infarction: insights from the National Cardiogenic Shock Initiative. Catheter Cardiovasc Interv 2020;96:1137-42.ArticlePubMed
  • 13. Cervera JP, López CAA, Romero RN, Macías JC, Asensio JM, Mínguez JR. Implementation of Society for Cardiovascular Angiography and Interventions classification in patients with cardiogenic shock secondary to acute myocardial infarction in a Spanish university hospital. Acute Crit Care 2024;39:257-65.ArticlePubMedPMCPDF
  • 14. Thayer KL, Zweck E, Ayouty M, Garan AR, Hernandez-Montfort J, Mahr C, et al. Invasive hemodynamic assessment and classification of in-hospital mortality risk among patients with cardiogenic shock. Circ Heart Fail 2020;13:e007099. ArticlePubMedPMC
  • 15. Vahdatpour C, Collins D, Goldberg S. Cardiogenic shock. J Am Heart Assoc 2019;8:e011991. ArticlePubMedPMC
  • 16. Lüsebrink E, Binzenhöfer L, Adamo M, Lorusso R, Mebazaa A, Morrow DA, et al. Cardiogenic shock. Lancet 2024;404:2006-20.ArticlePubMed
  • 17. Hartupee J, Mann DL. Neurohormonal activation in heart failure with reduced ejection fraction. Nat Rev Cardiol 2017;14:30-8.ArticlePubMedPDF
  • 18. Chioncel O, Parissis J, Mebazaa A, Thiele H, Desch S, Bauersachs J, et al. Epidemiology, pathophysiology and contemporary management of cardiogenic shock: a position statement from the Heart Failure Association of the European Society of Cardiology. Eur J Heart Fail 2020;22:1315-41.ArticlePubMed
  • 19. Thiele H, de Waha-Thiele S, Freund A, Zeymer U, Desch S, Fitzgerald S, et al. Management of cardiogenic shock. EuroIntervention 2021;17:451-65.ArticlePubMedPMC
  • 20. Naidu SS, Baran DA, Jentzer JC, Hollenberg SM, van Diepen S, Basir MB, et al. SCAI SHOCK stage classification expert consensus update: a review and incorporation of validation studies: this statement was endorsed by the American College of Cardiology (ACC), American College of Emergency Physicians (ACEP), American Heart Association (AHA), European Society of Cardiology (ESC) Association for Acute Cardiovascular Care (ACVC), International Society for Heart and Lung Transplantation (ISHLT), Society of Critical Care Medicine (SCCM), and Society of Thoracic Surgeons (STS) in December 2021. J Am Coll Cardiol 2022;79:933-46.ArticlePubMed
  • 21. Tehrani BN, Truesdell AG, Psotka MA, Rosner C, Singh R, Sinha SS, et al. A standardized and comprehensive approach to the management of cardiogenic shock. JACC Heart Fail 2020;8:879-91.ArticlePubMedPMC
  • 22. Britsch S, Britsch M, Hahn L, Langer H, Lindner S, Akin I, et al. Prognostic performance of the SCAI shock classification at admission and during ICU treatment: a retrospective, observational cohort study. Heart Lung 2024;68:52-9.ArticlePubMed
  • 23. Jentzer JC, Van Diepen S, Patel PC, Henry TD, Morrow DA, Baran DA, et al. Serial assessment of shock severity in cardiac intensive care unit patients. J Am Heart Assoc 2023;12:e032748. ArticlePubMedPMC
  • 24. Chlabicz M, Łaguna W, Kazimierczyk R, Kazimierczyk E, Łopatowska P, Gil M, et al. Value of APACHE II, SOFA and CardShock scoring as predictive tools for cardiogenic shock: a single-centre pilot study. ESC Heart Fail 2024;11:3584-97.ArticlePubMedPMCPDF
  • 25. Mierke J, Nowack T, Loehn T, Kluge F, Poege F, Speiser U, et al. Predictive value of the APACHE II score in cardiogenic shock patients treated with a percutaneous left ventricular assist device. Int J Cardiol Heart Vasc 2022;40:101013.ArticlePubMedPMC
  • 26. Stretch R, Sauer CM, Yuh DD, Bonde P. National trends in the utilization of short-term mechanical circulatory support: incidence, outcomes, and cost analysis. J Am Coll Cardiol 2014;64:1407-15.ArticlePubMed
  • 27. Alnasser S, Cavanagh M, Atoui R, Ali N, Nalla B, McKechnie K, et al. Utilization of shock team and veno-arterial extracorporeal membrane oxygenation (VA-ECMO) in the management of cardiogenic shock in Northern Ontario. CJC Open 2024;6:47-53.ArticlePubMed
  • 28. Blumer V, Hanff TC, Gage A, Schrage B, Kanwar MK. Cardiogenic shock teams: past, present, and future directions. Circ Heart Fail 2025;18:e011630. ArticlePubMed

Figure & Data

References

    Citations

    Citations to this article as recorded by  

      • PubReader PubReader
      • ePub LinkePub Link
      • Cite
        CITE
        export Copy
        Close
        Download Citation
        Download a citation file in RIS format that can be imported by all major citation management software, including EndNote, ProCite, RefWorks, and Reference Manager.
        Format:
        • RIS — For EndNote, ProCite, RefWorks, and most other reference management software
        • BibTeX — For JabRef, BibDesk, and other BibTeX-specific software
        Include:
        • Citation for the content below
        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
        Acute Crit Care. 2026;41(1):117-125.   Published online February 27, 2026
        DOI: https://doi.org/10.4266/acc.004500
        Close
      • XML DownloadXML Download
      Figure
      • 0
      • 1
      • 2
      • 3
      • 4
      Related articles
      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
      Image Image Image Image Image
      Figure 1. Flowchart of study population selection. The flowchart illustrates the process of selecting the study cohort. Among 24,752 cardiology patients admitted to the medical intensive care unit (MICU) or cardiovascular care unit (CCU) during the study period, those admitted for simple monitoring or same-day procedures were excluded. After excluding readmissions, 3,074 patients were included in the final analysis and classified according to Society for Cardiovascular Angiography and Interventions cardiogenic shock stage.
      Figure 2. Intensive care unit (ICU) mortality by Society for Cardiovascular Angiography and Interventions (SCAI) cardiogenic shock (CS) stage. ICU mortality increased stepwise with higher SCAI staging, rising from 0.5% in stage A to 53.2% in stage E (P<0.001).
      Figure 3. Kaplan-Meier curves for 30-day intensive care unit survival according to Society for Cardiovascular Angiography and Interventions (SCAI) stage. Analysis revealed that 30-day survival declined progressively with SCAI stage increase (log-rank P<0.001), demonstrating the classification’s prognostic discrimination.
      Figure 4. Kaplan-Meier curves for 60-day in-hospital survival according to Society for Cardiovascular Angiography and Interventions (SCAI) stage. Analysis revealed that 60-day survival was significantly lower with advanced SCAI staging (log-rank P<0.001), indicating sustained prognostic separation.
      Figure 5. Receiver operating characteristic curves for intensive care unit (ICU) mortality prediction. Receiver operating characteristic curves comparing the predictive performance of the Cardiovascular Angiography and Interventions (SCAI) cardiogenic shock (CS) classification, Acute Physiology and Chronic Health Evaluation (APACHE) II score, and the combination of both for ICU mortality. The area under the receiver operating characteristic curve values were 0.787 (95% CI, 0.756–0.819) for the SCAI classification, 0.909 (95% CI, 0.888–0.930) for APACHE II, and 0.927 (95% CI, 0.911–0.944) for the combined model. a) The combined model demonstrated significantly higher discriminative performance than the SCAI CS classification alone (P<0.001), indicating the complementary prognostic value of integrating APACHE II with the SCAI CS classification.

      Figure 1.

      Figure 2.

      Figure 3.

      Figure 4.

      Figure 5.

      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
      Variable Stage A (n=858) Stage B (n=328) Stage C (n=1,490) Stage D (n=304) Stage E (n=94) P-value
      Demographics
       Age (yr) 71±13 69±14 67±15 69±14 68±14 <0.001
       Female 359 (41.8) 139 (42.4) 577 (38.7) 119 (39.1) 40 (42.6) 0.508
       BMI (kg/m2) 23.54±3.86 22.69±4.23 23.01±3.99 22.88±3.54 24.40±4.87 0.001
      Admission ICD-10 diagnosis
       Myocardial infarction 313 (38.6) 85 (27.2) 432 (30.4) 100 (35.2) 29 (31.5) <0.001
       Heart failure 114 (14.4) 70 (23.0) 162 (11.4) 35 (12.2) 10 (10.9) <0.001
       Cardiac arrest 24 (2.8) 14 (4.3) 47 (3.2) 22 (7.2) 12 (12.8) <0.001
       Atrial fibrillation 58 (6.8) 47 (14.3) 132 (8.9) 19 (6.3) 10 (10.6) 0.001
       Ventricular tachycardia/fibrillation 19 (2.2) 8 (2.4) 47 (3.2) 7 (2.3) 1 (1.1) 0.528
      APACHE II score 12.18±6.09 17.36±8.69 14.96±10.99 23.24±11.58 32.55±12.75 <0.001
       Admission vital signs
        Systolic blood pressure (mm Hg) 126.43±38.79 102.86±41.27 113.52±49.53 94.92±50.00 61.84±52.39 <0.001
        Diastolic blood pressure (mm Hg) 68.65±20.66 63.83±23.75 65.19±25.78 56.82±27.98 38.82±32.74 <0.001
        Mean blood pressure (mm Hg) 87.95±25.06 76.96±28.59 81.30±32.62 69.59±34.68 46.65±37.62 <0.001
        Heart rate (beats/min) 77.68±62.07 102.10±36.51 77.96±36.24 84.50±45.82 62.56±55.83 <0.001
        Respiratory rate (breaths/min) 30.62±19.05 31.52±17.94 25.36±16.65 26.65±17.59 19.91±20.14 <0.001
        Urine output first 24 hours (L) 1.86±9.19 1.93±9.73 4.11±7.83 9.54±1.75 1.08±1.82 <0.001
       Admission laboratory data
        Maximum lactate first 24 hours (mmol/L) 1.63±1.08 2.82±2.52 5.06±4.70 7.21±5.48 11.25±7.05 <0.001
        Creatinine (mg/dl) 1.10±0.72 1.15±0.61 1.56±1.92 2.38±2.51 1.99±2.03 <0.001
        BUN (mg/dl) 20.35±13.00 23.91±16.06 21.74±15.43 32.29±23.94 32.13±20.89 <0.001
        ALT (U/L) 43.60±107.58 90.66±276.37 86.30±387.42 177.60±549.85 395.63±836.62 <0.001
        AST (U/L) 57.77±120.45 127.68±438.45 113.48±549.86 299.89±953.19 698.60±1544.44 <0.001
        Peak troponin-I first 24 hours (ng/ml) 8.81±30.18 8.17±31.20 6.12±21.36 7.81±15.97 16.57±68.13 0.247
        Hemoglobin (g/dl) 12.10±2.06 11.69±2.16 12.14±2.21 11.63±2.46 11.62±2.50 0.001
        Arterial pH 7.41±0.07 7.39±0.10 7.39±0.11 7.37±0.13 7.27±0.18 <0.001
        Bicarbonate (mEq/L) 24.01±3.77 22.75±4.72 22.38±4.65 20.68±4.90 17.87±7.83 <0.001
      Advanced therapies and procedures Stage A (n=858) Stage B (n=328) Stage C (n=1,490) Stage D (n=304) Stage E (n=94) P-value
      IABP 26 (3.4) 35 (14.6) 49 (3.8) 41 (30.1) 15 (42.9) <0.001
      ECMO 7 (0.8) 14 (4.3) 34 (2.3) 39 (12.8) 32 (34.0) <0.001
      CRRT 22 (2.6) 20 (6.1) 82 (5.5) 97 (31.9) 44 (46.8) <0.001
      Mechanical ventilation 102 (11.9) 90 (27.4) 201 (13.5) 166 (54.6) 67 (71.3) <0.001
      Invasive coronary angiography 447 (52.1) 140 (42.7) 825 (55.4) 166 (54.6) 57 (60.6) <0.001
      Percutaneous coronary intervention 315 (36.7) 95 (29.0) 544 (36.5) 120 (39.5) 33 (35.1) 0.060
      Table 1. Baseline characteristics

      Values are presented as number (%). The P-value is for the trend across SCAI cardiogenic shock stages A to E.

      BMI: body mass index; ICD-10: International Classification of Diseases, Tenth Revision; APACHE: Acute Physiology and Chronic Health Evaluation; BUN: blood urea nitrogen; ALT: alanine aminotransferase; AST: aspartate aminotransferase; SCAI: Society for Cardiovascular Angiography and Interventions.

      Table 2. Use of advanced therapies and procedures during the ICU stay according to SCAI cardiogenic shock stage

      Values are number (%). The P-value is for the trend across SCAI cardiogenic shock stages A to E.

      ICU: intensive care unit; SCAI: Society for Cardiovascular Angiography and Interventions; IABP: intra-aortic balloon pump; ECMO: extracorporeal membrane oxygenation; CRRT: continuous renal replacement therapy.

      Table 1.

      Table 2.

      ACC : Acute and Critical Care
      © The Korean Society of Critical Care Medicine.
      TOP