atherosclerosis of coronaryartery bypass graft (s) andcoronary artery oftransplanted heart with anginapectoris (I25.7-)

postinfarction angina (I23.7)Section I.C.9.b. ICD-10-CM

has combination codes for atheroscleroticheart disease with angina pectoris. Thesubcategories for these codes are I25.11,Atherosclerotic heart disease of nativecoronary artery with angina pectoris and I25.7,Atherosclerosis of coronary artery bypassgraft(s) and coronary artery of transplantedheart with angina pectoris.When using one of these combination codes itis not necessary to use an additional code forangina pectoris. A causal relationship can beassumed in a patient with both atherosclerosisand angina pectoris, unless the documentationindicates the angina is due to something otherthan the atherosclerosis. If a patient withcoronary artery disease is admitted due to anacute myocardial infarction (AMI), the AMIshould be sequenced before the coronaryartery disease.

Do not assign a code from I20.-for a patient who also has coronary arterydisease (CAD)/atherosclerotic heart disease(ASHD). Angina in a patient with CAD/ASHDshould be coded to the appropriate I25.11-code.

I20.0 Unstable anginaAccelerated anginaCrescendo anginaDe novo effort anginaIntermediate coronary syndromePreinfarction syndromeWorsening effort angina

Unstable angina is alsoknown as angina at rest.

I20.1 Angina pectoris with documented spasmAngiospastic anginaPrinzmetal anginaSpasm-induced anginaVariant angina

I20.8 Other forms of angina pectorisAngina equivalentAngina of effortCoronary slow flow syndromeStenocardiaStable anginaUse additional code(s) for symptoms

associated with angina equivalentI20.9 Angina pectoris, unspecified

Angina NOSAnginal syndromeCardiac anginaIschemic chest pain

I21 Acute myocardial infarctioncardiac infarctioncoronary (artery) embolismcoronary (artery) occlusioncoronary (artery) rupturecoronary (artery) thrombosisinfarction of heart,

myocardium, or ventriclemyocardial infarction specified

as acute or with a statedduration of 4 weeks (28 days)or less from onset

Use additional code, if applicable, to identify:exposure to environmental tobacco smoke

(Z77.22)history of tobacco dependence (Z87.891)occupational exposure to environmental

tobacco smoke (Z57.31)status post administration of tPA (rtPA) in a

different facility within the last 24 hoursprior to admission to current facility(Z92.82)

tobacco dependence (F17.-)tobacco use (Z72.0)

old myocardial infarction(I25.2)

postmyocardial infarctionsyndrome (I24.1)

subsequent type 1 myocardialinfarction (I22.-)Section I.C.9.e.4)

If a subsequent myocardial infarction of onetype occurs within 4 weeks of a myocardialinfarction of a different type, assign theappropriate codes from category I21 to identifyeach type. Do not assign a code from I22.Codes from category I22 should only beassigned if both the initial and subsequentmyocardial infarctions are type 1 orunspecified.

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Section I.C.9.e.1)The ICD-10-CM codes for type 1 acutemyocardial infarction (AMI) identify the site,such as anterolateral wall or true posterior wall.Subcategories I21.0-I21.2 and code I21.3 areused for type 1 ST elevation myocardialinfarction (STEMI). Code I21.4, Non-STelevation (NSTEMI) myocardial infarction, isused for type 1 non ST elevation myocardialinfarction (NSTEMI) and nontransmural MIs.If a type 1 NSTEMI evolves to STEMI, assignthe STEMI code. If a type 1 STEMI converts toNSTEMI due to thrombolytic therapy, it is stillcoded as STEMI.

When assigning any code fromI21.- to report STEMI or NSTEMI, note thatICD-10 coding guidelines only allowassignment of these codes for 4 weeksfollowing the occurrence of the MI. Use I22codes for any subsequent MI during the same4 weeks, if both the initial and subsequent MIwere Type 1 or unspecified.

I21 codes specify STEMI or STelevation myocardial infarction. If the physicianhas not documented STEMI, but hasdocumented location, use the specific I21 codefor that location. STEMI is more common thanNSTEMI, and is the default.

I21.0 ST elevation (STEMI) myocardialinfarction of anterior wallType 1 ST elevation myocardial infarction

of anterior wallI21.01 ST elevation (STEMI) myocardial

infarction involving left maincoronary artery

I21.02 ST elevation (STEMI) myocardialinfarction involving left anteriordescending coronary arteryST elevation (STEMI) myocardial

infarction involving diagonalcoronary artery

I21.09 ST elevation (STEMI) myocardialinfarction involving other coronaryartery of anterior wallAcute transmural myocardial infarction

of anterior wallAnteroapical transmural (Q wave)

infarction (acute)Anterolateral transmural (Q wave)

infarction (acute)Anteroseptal transmural (Q wave)

infarction (acute)Transmural (Q wave) infarction (acute)

(of) anterior (wall) NOSI21.1 ST elevation (STEMI) myocardial

infarction of inferior wallType 1 ST elevation myocardial infarction

of inferior wallI21.11 ST elevation (STEMI) myocardial

infarction involving right coronaryarteryInferoposterior transmural (Q wave)

infarction (acute)I21.19 ST elevation (STEMI) myocardial

infarction involving other coronaryartery of inferior wallAcute transmural myocardial infarction

of inferior wall

Inferolateral transmural (Q wave)infarction (acute)

Transmural (Q wave) infarction (acute)(of) diaphragmatic wall

Transmural (Q wave) infarction (acute)(of) inferior (wall) NOS

ST elevation (STEMI)myocardial infarctioninvolving leftcircumflex coronaryartery (I21.21)

I21.2 ST elevation (STEMI) myocardialinfarction of other sitesType 1 ST elevation myocardial infarction

of other sitesI21.21 ST elevation (STEMI) myocardial

infarction involving left circumflexcoronary arteryST elevation (STEMI) myocardial

infarction involving oblique marginalcoronary artery

I21.29 ST elevation (STEMI) myocardialinfarction involving other sitesAcute transmural myocardial infarction

of other sitesApical-lateral transmural (Q wave)

infarction (acute)Basal-lateral transmural (Q wave)

infarction (acute)High lateral transmural (Q wave)

infarction (acute)Lateral (wall) NOS transmural (Q

wave) infarction (acute)Posterior (true) transmural (Q wave)

infarction (acute)Posterobasal transmural (Q wave)

infarction (acute)Posterolateral transmural (Q wave)

infarction (acute)Posteroseptal transmural (Q wave)

infarction (acute)Septal transmural (Q wave) infarction

(acute) NOSI21.3 ST elevation (STEMI) myocardial

infarction of unspecified siteAcute transmural myocardial infarction of

unspecified siteTransmural (Q wave) myocardial

infarction NOSType 1 ST elevation myocardial infarction

of unspecified siteThis code is used for a

documented STEMI, but of unspecifiedlocation. Do not use this code for MI, NOS.Do not use this code if the physician hasdocumented Type 2 MI.

I21.4 Non-ST elevation (NSTEMI) myocardialinfarctionAcute subendocardial myocardial

infarctionNon-Q wave myocardial infarction NOSNontransmural myocardial infarction NOSType 1 non-ST elevation myocardial

infarction

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Section I.C.9.e.1)Code I21.4, Non-ST elevation (NSTEMI)myocardial infarction, is used for type 1 nonST elevation myocardial infarction(NSTEMI) and nontransmural MIs.

Section I.C.9.e.3)If an AMI is documented as nontransmuralor subendocardial, but the site is provided,it is still coded as a subendocardial AMI.

I21.9 Acute myocardial infarction,unspecified

Myocardial infarction (acute) NOSSection I.C.9.e.2)

Code I21.9, Acute myocardial infarction,unspecified, is the default for unspecifiedacute myocardial infarction or unspecifiedtype. If only type 1 STEMI or transmural MIwithout the site is documented, assign codeI21.3, ST elevation (STEMI) myocardialinfarction of unspecified site.

This code is used for theinitial MI when the physician has notdocumented the type or location of theinfarct.

I21.A Other type of myocardial infarctionThere is no code for a

subsequent MI of types 2, 3, 4, 5. Continueto use I21.A-, remembering that a code canonly be used once on a POC/claim.

I21.A1 Myocardial infarction type 2Myocardial infarction due to demand

ischemiaMyocardial infarction secondary to

ischemic imbalanceCode first the underlying cause, such

as:anemia (D50.0-D64.9)chronic obstructive pulmonary

disease (J44.-)paroxysmal tachycardia

(I47.0-I47.9)shock (R57.0-R57.9)

Section I.C.9.e.5)The ICD-10-CM provides codes fordifferent types of myocardial infarction.Type 1 myocardial infarctions areassigned to codes I21.0-I21.4, andI21.9.Type 2 myocardial infarction, andmyocardial infarction due to demandischemia or secondary to ischemicbalance, is assigned to code I21.A1,Myocardial infarction type 2 with a codefor the underlying cause. Do not assigncode I24.8, Other forms of acuteischemic heart disease for the demandischemia. Sequencing of type 2 AMI orthe underlying cause is dependent onthe circumstances of admission. Whena type 2 AMI code is described asNSTEMI or STEMI, only assign codeI21.A1. Codes I21.01-I21.4 should onlybe assigned for type 1 AMIs.Acute myocardial infarctions type 3, 4a,4b, 4c and 5 are assigned to codeI21.A9, Other myocardial infarction type.The "Code also" and "Code first" notesshould be followed related tocomplications, and for coding ofpostprocedural myocardial infarctionsduring or following cardiac surgery.

When the physiciandocuments Type 2 MI, assign I21.A1,even if the physician documents STEMIor NSTEMI. Type 2 MIs are not due toatherosclerotic plaque, but to a problemwith supply and demand of oxygen. Thedocumented cause of the problemshould be coded first.!QE

I21.A9 Other myocardial infarction typeMyocardial infarction associated with

revascularization procedureMyocardial infarction type 3Myocardial infarction type 4aMyocardial infarction type 4bMyocardial infarction type 4cMyocardial infarction type 5Code first:

, if applicable, postproceduralmyocardial infarction followingcardiac surgery (I97.190) , orpostprocedural myocardialinfarction during cardiac surgery(I97.790)

Code also complication, if known andapplicable, such as:(acute) stent occlusion (T82.897-)(acute) stent stenosis (T82.855-)(acute) stent thrombosis (T82.867-)cardiac arrest due to underlying

cardiac condition (I46.2)complication of percutaneous

coronary intervention (PCI)(I97.89)

occlusion of coronary artery bypassgraft (T82.218-)

I22 Subsequent ST elevation (STEMI) andnon-ST elevation (NSTEMI) myocardialinfarction

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