ICD-10 Code I24.81 – Acute coronary microvascular dysfunction (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I24.81 – Acute coronary microvascular dysfunction
What it is
This code identifies an acute episode of coronary microvascular dysfunction, meaning the small vessels supplying the heart are not working properly. It is used when documentation specifically names this diagnosis.
Clinical signs
Clinical features may include chest pain or ischemic symptoms with no major epicardial coronary blockage. Check documentation for evidence of microvascular ischemia or a provider statement linking symptoms to coronary microvascular dysfunction.
When to use this code
Use I24.81 when the record clearly documents acute coronary microvascular dysfunction as the reason for evaluation or treatment. It may appear in cardiology notes, discharge summaries, or problem lists when the clinician confirms this diagnosis. If the wording is nonspecific, code only what is documented.
Do not use for
Do not use this code for general chest pain, stable angina, or coronary artery disease without microvascular dysfunction. If the chart does not clearly support an acute microvascular diagnosis, check documentation.
Coding tip
Assign I24.81 only when the provider explicitly documents acute coronary microvascular dysfunction, not when it is merely suspected.