Diagnostic re-classification and prognostic risk stratification of patients with acute chest pain

Area of Science:

• Cardiology
• Clinical Medicine
• Biomarker Research

Background:

• Unstable angina and myocardial infarction are key forms of acute coronary artery disease, often grouped as acute coronary syndromes.
• Increasingly sensitive cardiac troponin assays blur the lines between minor myocardial infarctions and unstable angina, leading to reclassification.

Purpose of the Study:

• To evaluate the clinical relevance of the unstable angina diagnosis in light of modern diagnostic markers.
• To propose a revised terminology and diagnostic approach for acute chest pain presentations.

Main Methods:

• Review of existing studies on high-sensitivity cardiac troponin levels in patients presenting with acute chest pain.
• Analysis of prognostic data for patients with low troponin levels (<5 ng/l).

Main Results:

• Most patients with acute chest pain exhibit low high-sensitivity cardiac troponin levels (<5 ng/l).
• These patients demonstrate excellent prognoses (event rates <0.5% per year), inconsistent with 'impending infarction' definitions.
• The distinction between unstable angina and minor myocardial infarction is increasingly difficult and potentially clinically irrelevant.

Conclusions:

• The diagnosis of unstable angina should be abandoned.
• The term 'acute coronary syndromes' may lose its utility without the unstable angina classification.
• Reverting to 'thrombus-related acute coronary artery disease' or 'myocardial infarction' is recommended, supported by a national registry for monitoring and guiding therapy.