I21.A1
Myocardial infarction type 2
Billable FY2026 2025-10-01 → 2026-09-30
Exclusions 13 never code together
I21code
I00-I99chapter
Excludes2
- certain conditions originating in the perinatal period (P04-P96)P04-P96
- certain infectious and parasitic diseases (A00-B99)A00-B99
- complications of pregnancy, childbirth and the puerperium (O00-O9A)O00-O9A
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)Q00-Q99
- endocrine, nutritional and metabolic diseases (E00-E88)E00-E88
- injury, poisoning and certain other consequences of external causes (S00-T88)S00-T88
- neoplasms (C00-D49)C00-D49
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)R00-R94
- systemic connective tissue disorders (M30-M36)M30-M36
- transient cerebral ischemic attacks and related syndromes (G45.-)G45.-
Excludes2 — not included here, but the patient may have both. Code both when documented.
Instructional notes 22
I21code
Includes
- 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
Use additional code
- code, if applicable, to identify:
- exposure to environmental tobacco smoke (Z77.22)Z77.22
- history of tobacco dependence (Z87.891)Z87.891
- occupational exposure to environmental tobacco smoke (Z57.31)Z57.31
- status post administration of tPA (rtPA) in a different facility within the last 24 hours prior to admission to current facility (Z92.82)Z92.82
- tobacco dependence (F17.-)F17.-
- tobacco use (Z72.0)Z72.0
I21.A1code
Inclusion terms
- Myocardial infarction due to demand ischemia
- Myocardial infarction secondary to ischemic imbalance
Code first
- , if applicable, the underlying cause, such as:
- anemia (D50.0-D64.9)D50.0-D64.9
- chronic obstructive pulmonary disease (J44.-)J44.-
- paroxysmal tachycardia (I47.0-I47.9)I47.0-I47.9
- shock (R57.0-R57.9)R57.0-R57.9
Index entries leading here 2
- Ischemia, ischemic I99.8
- Infarct, infarction
Alongside this code 1 same parent — I21.A
Medications 2
MED-RT files conditions by MeSH, which carves the world differently from ICD-10. These are name matches on this code's description, offered as candidates — not as an assertion that they are this code.
Additional references
AHA Coding Clinic® Licence required
Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.