Myocardial infarction, acute (AMI), NOS
| ICD10 Diagnosis | |
| Dx: | Myocardial infarction, acute (AMI), NOS |
| ICD10 code: | I21.9 |
| Pre-ICD10 counterpart: | Myocardial infarction |
| Charlson/ALERT Scale: | Myocardial infarction |
| APACHE Como Component: | none |
| APACHE Acute Component: | 2019-0: Coronary Artery Disease |
| Start Date: | |
| Stop Date: | |
| External ICD10 Documentation | |
This diagnosis is a part of ICD10 collection.
Additional Info
This code is only used for an Acute Myocardial Infarction (AMI) when the more specific type is unknown(i.e. Q-wave, non-Q-wave).
MI - type vs mechanism
MIs are occasionally listed as "Type 2 MIs", ie no evidence of coronary artery disease (CAD). This refers to the mechanism, and the AMI codes include any/all mechanisms (including coronary artery embolism, thrombosis or thromboembolism); said another way, we don't particularly care about the mechanism. They should be coded based on their manifestation.
In ICD10, this will mean:
- Code the appropriate AMI code:
- Code the cause separately, as a Combined ICD10 codes. For example it might be one of the following:
MI - acute vs past history
To decide whether to code an acute MI dx in the Admit Diagnosis or Acquired Diagnosis / Complication, or a Past history, myocardial infarction (old MI) in the Comorbid Diagnosis, consider the following:
- Regarding an MI that occured prior to the current hospitalization -- might be coded as either Comorbid Diagnosis, or a Past history, myocardial infarction (old MI)
- In ICD10 the code for Past history, myocardial infarction (old MI) reads as follows: Healed myocardial infarction -- Past myocardial infarction diagnosed by ECG or other special investigation, but currently presenting no symptoms.
- If the prior MI is still active and we're not dealing with any current complications of it, then instead use one of the AMI codes, as a Comorbid Diagnosis.
- If the prior MI is still active and we are dealing with any current complications of it, then instead use one of the AMI codes, as a Admit Diagnosis.
- Examples: Papillary muscle rupture or Ongoing angina related to a recent MI prior to this unit/ward admission.
- For a missed MI: code it as one of the "...acute..." codes if the missed MI is being treated as an acute MI
Alternate ICD10s to consider coding instead or in addition
| Ischemic heart disease codes: |
| Myocardial Infarction codes: |
| Arterial thromboembolism codes: |
Candidate Combined ICD10 codes
- Also code any acute complications from Myocardial Infarction list.
Related CCI Codes
Data Integrity Checks (automatic list)
none found
Related Articles
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