I21.21
BillableST elevation (STEMI) myocardial infarction involving left circumflex coronary artery
I21.21 is the ICD-10-CM code for ST elevation (STEMI) myocardial infarction involving left circumflex coronary artery. It is a billable, specific code valid for reimbursement.
I00-I99 Diseases of the circulatory system
What this means — in plain language
MedlinePlus · NIHEach year almost 800,000 Americans have a heart attack. A heart attack happens when blood flow to the heart suddenly becomes blocked. Without the blood coming in, the heart can't get oxygen. If not treated quickly, the heart muscle begins to die. But if you do get quick treatment, you may be able to prevent or limit damage to the heart muscle. That's why it's important to know the symptoms of a heart attack and call…
Read more about Heart Attack at MedlinePlus ↗Source: U.S. National Library of Medicine (MedlinePlus). Informational only — not medical advice.
Includes
- •ST elevation (STEMI) myocardial infarction involving oblique marginal coronary artery
Frequently asked questions
- What is ICD-10 code I21.21?
- I21.21 is the ICD-10-CM code for "ST elevation (STEMI) myocardial infarction involving left circumflex coronary artery". It falls under I00-I99 Diseases of the circulatory system.
- Is I21.21 a billable code?
- Yes — I21.21 is a billable, specific ICD-10-CM code valid for reimbursement.
Source: CMS ICD-10-CM FY2026. For informational purposes only — not medical advice. See our medical disclaimer.
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