ST elevation (STEMI) myocardial infarction of unspecified site
Billable / specificHCC V28 228
I21.3 is a billable, specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes in FY2027.
Inclusion terms
Applicable to
- Acute transmural myocardial infarction of unspecified site
- Transmural (Q wave) myocardial infarction NOS
- Type 1 ST elevation myocardial infarction of unspecified site
Includes (from I21)
- cardiac infarction
- coronary (artery) embolism
- coronary (artery) occlusion
- coronary (artery) rupture
- coronary (artery) thrombosis
- infarction of heart, myocardium, or ventricle
- myocardial infarction specified as acute or with a stated duration of 4 weeks (28 days) or less from onset
Excludes2
Not included here — may be reported together when both conditions exist.
- certain conditions originating in the perinatal period (P04-P96) (from I21)
- certain infectious and parasitic diseases (A00-B99) (from I21)
- complications of pregnancy, childbirth and the puerperium (O00-O9A) (from I21)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99) (from I21)
- endocrine, nutritional and metabolic diseases (E00-E88) (from I21)
- injury, poisoning and certain other consequences of external causes (S00-T88) (from I21)
- neoplasms (C00-D49) (from I21)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94) (from I21)
- systemic connective tissue disorders (M30-M36) (from I21)
- transient cerebral ischemic attacks and related syndromes (G45.-) (from I21)
- old myocardial infarction (I25.2) (from I21)
- postmyocardial infarction syndrome (I24.1) (from I21)
- subsequent type 1 myocardial infarction (I22.-) (from I21)
Use additional code
Add a code to identify the following, if applicable.
- code, if applicable, to identify: (from I21)
- exposure to environmental tobacco smoke (Z77.22) (from I21)
- history of tobacco dependence (Z87.891) (from I21)
- occupational exposure to environmental tobacco smoke (Z57.31) (from I21)
- status post administration of tPA (rtPA) in a different facility within the last 24 hours prior to admission to current facility (Z92.82) (from I21)
- tobacco dependence (F17.-) (from I21)
- tobacco use (Z72.0) (from I21)
Code also
An additional code may be needed.
Also known as
- Acute transmural myocardial infarction of unspecified site
- Transmural (Q wave) myocardial infarction NOS
- Type 1 ST elevation myocardial infarction of unspecified site
- Infarct, infarction, myocardium, myocardial, Q wave
- Infarct, infarction, myocardium, myocardial, ST elevation
- Infarct, infarction, myocardium, myocardial, transmural
- STEMI
Parent code
- I21Acute myocardial infarctionHeader
Related codes
- I21.0ST elevation (STEMI) myocardial infarction of anterior wallHeader
- I21.1ST elevation (STEMI) myocardial infarction of inferior wallHeader
- I21.2ST elevation (STEMI) myocardial infarction of other sitesHeader
- I21.4Non-ST elevation (NSTEMI) myocardial infarctionBillable
- I21.9Acute myocardial infarction, unspecifiedBillable
- I21.AOther type of myocardial infarctionHeader
- I21.BMyocardial infarction with coronary microvascular dysfunctionBillable