How to Document an NSTEMI Diagnosis
Document NSTEMI when you have evidence of myocardial necrosis (elevated cardiac troponin with rise/fall pattern, at least one value >99th percentile) in a clinical setting consistent with acute myocardial ischemia, WITHOUT ST-segment elevation on ECG. 1
Required Diagnostic Elements
Your documentation must include these specific components to establish NSTEMI 1, 2:
1. Cardiac Biomarker Evidence
- Troponin elevation: Document at least one cardiac troponin (cTn) value above the 99th percentile upper reference limit (URL)
- Dynamic pattern: Must show rise and/or fall of values (not just a single elevated value)
- Include specific troponin values with timing in your documentation
2. Clinical Evidence of Ischemia (at least ONE required)
- Symptoms: Chest pain, dyspnea, or anginal equivalents
- ECG changes: New or presumed new ST-segment depression, T-wave inversion, or other ischemic changes (but NOT ST-elevation in ≥2 contiguous leads)
- Imaging findings: New loss of viable myocardium or new regional wall motion abnormality on echocardiography, MRI, or nuclear imaging
- Angiographic evidence: Intracoronary thrombus identified on coronary angiography
3. ECG Documentation
- Explicitly state "no ST-segment elevation" or "ST-segment depression" or "T-wave inversion" 2
- Document that ST-elevation criteria are NOT met (i.e., no ST-elevation ≥1mm in ≥2 contiguous leads)
- Note any other ECG abnormalities present
Critical Documentation Pitfalls
Avoid inconsistent terminology 3: Research shows MI type is discrepant across chart sections in >10% of cases and missing entirely in 8.4%. This creates problems for patient care continuity and research.
Use standardized terminology:
- Write "NSTEMI" or "Non-ST-elevation myocardial infarction"
- Avoid outdated terms like "subendocardial MI" or "non-Q wave MI" alone without clarifying NSTEMI
- Be consistent across admission notes, progress notes, and discharge summary 3
Specify MI Type Classification
Document the Type of MI according to the Universal Definition 2:
- Type 1: Acute coronary atherothrombosis (plaque rupture/erosion with thrombosis) - most common NSTEMI
- Type 2: Supply-demand mismatch unrelated to acute atherothrombosis (e.g., severe anemia, hypotension, tachyarrhythmia, coronary vasospasm)
Essential Clinical Context
Include in your documentation:
- Timing: When symptoms began, when troponin was first elevated, serial troponin values
- Risk stratification: GRACE or TIMI score if calculated
- Coronary anatomy: Single-vessel vs. multivessel disease if known from angiography 4
- Procedural MI: If post-PCI, document troponin >5× 99th percentile URL with ischemic symptoms, ECG changes, or angiographic complications 1
Documentation Template Structure
Diagnosis: Non-ST-elevation myocardial infarction (NSTEMI), Type 1
Supporting Evidence:
- Troponin I: [value] ng/L at [time], rising to [value] ng/L at [time] (>99th percentile URL of [value])
- Clinical: Substernal chest pressure lasting 30 minutes
- ECG: ST-segment depression 2mm in leads V4-V6, no ST-elevation
- Angiography: [findings if performed]
Common pitfall: Approximately 1-8% of NSTEMI patients present with completely normal initial ECGs 5. In these cases, emphasize the troponin dynamics and clinical presentation even more strongly, and document serial ECGs performed.