I21.19: ST elevation (STEMI) myocardial infarction involving other coronary artery of inferior wall
I21.19 is a billable, specific ICD-10-CM code for st elevation (stemi) myocardial infarction involving other coronary artery of inferior wall. It is valid for submission on a claim.
Check I21.19 with the rest of the claim: free scrubberExcludes2: not included here, but may coexist
The excluded condition is not part of this code, but a patient can have both. You may code both.
- ST elevation (STEMI) myocardial infarction involving left circumflex coronary artery (I21.21)
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Acute transmural myocardial infarction of inferior wall
- Inferolateral transmural (Q wave) infarction (acute)
- Transmural (Q wave) infarction (acute) (of) diaphragmatic wall
- Transmural (Q wave) infarction (acute) (of) inferior (wall) NOS
Other codes that can never be billed with I21.19
Their own Excludes1 notes name this code, so the conflict is not listed above.
- I5ANon-ischemic myocardial injury (non-traumatic)
Risk adjustment
I21.19 risk-adjusts. Under the CMS-HCC V28 model it maps to this category:
- HCC 228 Acute Myocardial Infarction0.252 RAF
Coefficient shown for the Community Non-dual Aged segment. A higher HCC in the same hierarchy will suppress this one, so capturing it does not always add score. Look up the whole chart to see which of its HCCs the hierarchy would zero.
Medicare coverage
I21.19 is named in 46 Medicare coverage policies: 46 listing it as supporting medical necessity. Which one applies depends on your Medicare contractor.
- A52458Automatic External Defibrillators - Policy Article
- A52850Billing and Coding: Cardiac Catheterization and Coronary Angiography
- A53775Billing and Coding: Frequency and Duration for Cardiac Rehabilitation and Intensive Cardiac Rehabilitation
- A56423Billing and Coding: Cardiology Non-emergent Outpatient Stress Testing
Alphabetic index entries that lead here
- Infarct, infarction›myocardium, myocardial›ST elevation›inferior NEC(diaphragmatic) (inferolateral) (inferoposterior) (wall)
- Infarct, infarction›myocardium, myocardial›transmural›inferior NEC(diaphragmatic) (inferolateral) (inferoposterior) (Q wave) (wall)
- Infarct, infarction›myocardium, myocardial›ST elevation›involving›coronary artery of inferior wall NEC
Code history
Unchanged in every release from FY2024 to FY2027.