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If an AMI is documented as nontrasmural or subendocarial, but the site is provided, it is still coded as a subendocarial AMI.Old or healed MIs not requiring further care should be coded to I25.2, Old myocardial infarction. For encounters after the 4-week timeframe and the patient is still receiving care related to the MI, the appropriate aftercare code should be assigned instead of a code from I21. For encounters occurring while the MI is equal to or less than 4 weeks old, including transfers to another acute or postacute setting, and the MI meets the definition for “other diagnoses”, codes from category I21 may continue to be reported.If a type 1 STEMI converts to NSTEMI due to thrombolytic therapy, it is still coded as STEMI.If a type 1 NSTEMI evolves to STEMI, assign the STEMI code.Code I21.A9 is used for types 3, 4a, 4b, 4c, and 5 MI.Code I21.9 is used for unspecified AMI or unspecified type.Code I21.4 is used for type 1 NSTEMI MI and nontransmural MIs.How is type 2 myocardial infarction diagnosed Background.
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4 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes. If the provider documents acute MI but does not include the specific location, the appropriate code is to assign is I21.3. Non-ST elevation (NSTEMI) myocardial infarction I21.Codes I21.01-I21.3 are used for type 1 STEMI MI.The ICD-10-CM codes for type 1 STEMI and NSTEMI identify the site, such as the anterolateral wall or true posterior wall.Based on the ICD-10-CM Official Guidelines for Coding and Reporting ( FY2022), keep the following in mind when coding from category I21:
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