Past history, myocardial infarction (old MI)
|Dx:||Past history, myocardial infarction (old MI)|
|Pre-ICD10 counterpart:||none assigned|
|Charlson/ALERT Scale:||Myocardial infarction|
|APACHE Como Component:||none|
|APACHE Acute Component:||Chronic Cardiac Disease, Coronary Artery Disease|
|External ICD10 Documentation|
- This is a code that specifically represent a situation where the person had an acute MI sometime in the past (could be ancient past, or even weeks) that is now HEALED.
- By healed we mean that there are no longer any symptoms or signs of that acute MI, such as acute chest pain, ECG changes consistent with AMI (e.g. acute ST-T changes which suggest acute MI, vs. completed set of Q-waves without any acute-looking ST-T changes which suggest OLD MI, etc.)
- This doesn't preclude having acute symptoms of an new AMI while also having an old/healed MI.
- It also doesn't preclude having cardiac symptoms ongoing that are an INDIRECT consequence of the old healed MI -- e.g. CHF symptoms.
- Obviously, this determination can be very hard when the person has symptoms of ongoing CHF, or has now another AMI.
- The person does not need to ever have had a recognized AMI --- it can have been silent and now only known about because of a set of Q-waves persisting on the ECG.
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:
- Coronary artery disease, chronic (atherosclerosis, chronic ischemic heart disease)
- Ischemic heart disease, acute NOS
- anemia - Category:Anemia
- hypovolemia - [[Dehydration (volume depletion, hypovolemia)]
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.
Past medical history codes
Past medical history codes should only be captured as Comorbid Diagnoses that represent previous procedures or medical situations that can't be captured in another way. Their names usually follow the pattern "Past history of X" or "X, has one". See Category:Past medical history for a list.
Alternate ICD10s to consider coding instead or in addition
Candidate Combined ICD10 codes
Related CCI Codes
Data Integrity Checks (SMW)