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

Article information

Acute Crit Care. 2026;41(1):117-125

Publication date (electronic) : 2026 February 27

doi : https://doi.org/10.4266/acc.004500

Haechan Cho ¹^,²

, Jeehoon Kang^,³^,⁴

, Minju Han ³^,⁴

, Huijin Lee ³^,⁴

, Hyun-Jai Cho ³^,⁴

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 2025 October 1; Revised 2025 December 7; Accepted 2025 December 18.

Abstract

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.

Keywords: cardiogenic shock; intensive care units; risk assessment

INTRODUCTION

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.

MATERIALS AND METHODS

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).

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.

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).

RESULTS

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.

Table 1.

Baseline characteristics

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).

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.

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).

Table 2.

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

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.

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.

DISCUSSION

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.

KEY MESSAGES

▪ 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.

Notes

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

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

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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.

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