Abstract 12197: China PEACE Risk Tool for Acute Myocardial Infarction: An Early Risk Classification Tree for Decisions About Fibrinolytic Therapy

Abstract

Introduction: Timely fibrinolytic therapy is recommended to reduce short-term mortality for patients with ST-elevation myocardial infarction (STEMI). However, the absolute treatment benefit is related to baseline mortality risk, and may be offset by the risks of major bleeding for low-risk patients. We constructed a baseline risk-assessment tool in eligible but untreated patients, to estimate the absolute benefits from fibrinolytic treatment. Methods: The China PEACE study includes a nationally representative sample of patients admitted with acute myocardial infarction (AMI) in 162 Chinese hospitals. Comprehensive clinical information was centrally abstracted from medical records using standardized data definitions. We identified 3741 patients with STEMI who were fibrinolytic-eligible, but did not receive reperfusion therapy, and separated the cohort randomly into derivation and validation cohorts. We employed classification and regression tree methods to produce a simple algorithm to estimate the risk of in-hospital mortality. Results: The overall in-hospital mortality rate was 14.7%. In both derivation and validation cohorts, the combination of systolic blood pressure (≥ 100 mm Hg), age (< 60 years old), and male gender identified one fifth of the patients with an average mortality risk less than 3.0%; half of this group with a non-anterior AMI had an average in-hospital mortality risk of 1.5%. The classification tree performed consistently across study years, and in hospitals with or without PCI capability. Conclusions: Nearly one in five fibrinolytic-eligible patients with STEMI have an low estimated risk of death, with an absolute benefit of fibrinolytic therapy could be insufficient to justify the risks of major bleeding. The tool with three simple factors, easily available at hospital presentation, can identify these individuals and support decision-making about the use of fibrinolytic therapy.