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Published on: August 16, 2021
CSWG-SCAI Stages Combined With Machine Learning-Based Phenotypes for Serial Risk Stratification in Cardiogenic Shock
Elric Zweck1, Van-Khue Ton2, Manreet Kanwar3
1The CardioVascular Center, Tufts Medical Center, Boston, Massachusetts, USA; Department of Cardiology, Pulmonology, and Vascular Medicine, University Hospital Duesseldorf, Duesseldorf, Germany.
Combining machine learning phenotypes with SCAI stages improves risk stratification for cardiogenic shock (CS) patients. This approach offers a mechanistic classification reflecting CS heterogeneity, aiding clinical decision-making.
Area of Science:
- Cardiology
- Medical Informatics
- Critical Care Medicine
Background:
- Cardiogenic shock (CS) severity is currently classified using Society for Cardiovascular Angiography and Interventions (SCAI) stages (A-E) or machine learning (ML)-based phenotypes (I: noncongested, II: cardiorenal, III: cardiometabolic).
- These classification systems aim to define and stratify patients based on their clinical status.
Purpose of the Study:
- To evaluate the sequential applicability and prognostic relevance of combining SCAI stages and ML-based phenotypes for risk stratification in CS patients.
- To determine if a combined classification approach offers improved accuracy in predicting outcomes compared to individual systems.
Main Methods:
- Retrospective analysis of 7,716 patients from the Cardiogenic Shock Working Group (CSWG) registry.
- Application of both SCAI staging and ML-based phenotypes at 6- to 12-hour intervals for the first 72 hours.
- Primary outcome assessed was in-hospital mortality.
Main Results:
- Within 6 hours of admission, 78% of patients showed changes in SCAI stages and 77% in phenotypes, with relative stability thereafter.
- Combining ML-based phenotypes with SCAI stages significantly improved risk stratification, with distinct mortality rates for combined categories (e.g., C-I: 12%-14% vs. D-III: 37%-40%).
- Phenotypes II and III were strong predictors of CS progression and in-hospital mortality (Phenotype III: OR 11.4, P < 0.0001).
Conclusions:
- Most CS patients reach phenotype I and stage D within 6 hours of admission.
- Integrating ML-based phenotypes with SCAI staging provides a more mechanistic classification of CS.
- This combined approach may enhance clinical decision-making by better reflecting the heterogeneity within CS populations.
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