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
Candidate Combined ICD10 codes
- Also code any acute complications from Myocardial Infarction list.
Related CCI Codes
Data Integrity Checks (automatic list)
none found
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