I20.0
BillableUnstable angina
Unstable angina
Coding Notes
Inclusion Terms
Alternative clinical terms for this condition
- Accelerated angina
- Crescendo angina
- De novo effort angina
- Intermediate coronary syndrome
- Preinfarction syndrome
- Worsening effort angina
Excludes 1
Codes that cannot be used together with this code (mutual exclusion)
Excludes 2
Conditions not included here, but the patient may have both
- •certain conditions originating in the perinatal periodP04-P96
- •certain infectious and parasitic diseasesA00-B99
- •complications of pregnancy, childbirth and the puerperiumO9A)O00
- •congenital malformations, deformations, and chromosomal abnormalitiesQ00-Q99
- •endocrine, nutritional and metabolic diseasesE00-E88
- •injury, poisoning and certain other consequences of external causesS00-T88
- •neoplasmsC00-D49
- •symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classifiedR00-R94
- •systemic connective tissue disordersM30-M36
- •transient cerebral ischemic attacks and related syndromesG45
Use Additional Code
Additional codes that should follow this code
Code Also
A second code may be required; sequencing depends on circumstances
Related Codes(4)
Related Conditions
ICD-11 Equivalents(1)
ICD-11 Equivalents
View full mappingCorresponding ICD-11 codes from the WHO crosswalk mapping
Also Known As / Clinical Terms(101)
SNOMED CT
- Crescendo angina4557003
- Intermediate coronary syndrome4557003
- Pre-infarction syndrome4557003
- Preinfarction angina4557003
- Preinfarction syndrome4557003
- Unstable angina4557003
- Worsening angina4557003
- Impending infarction25106000
- Angina control170593007
- Angina control - worsening170597008
- Refractory angina315025001
- Progressive angina371806006
- Chronic ischaemic heart disease413838009
- Chronic ischemic heart disease413838009
- Chronic chest pain434011000124101
UMLS
- Accelerated anginaC2882087
- Angina Pectori, UnstableC0002965
- Angina Pectoris, UnstableC0002965
- Angina at RestC0002965
- Angina at restC0002965
- Angina pectoris unstableC0002965
- Angina unstableC0002965
- Angina, PreinfarctionC0002965
- Angina, UnstableC0002965
- Anginas, PreinfarctionC0002965
- Anginas, UnstableC0002965
- Crescendo anginaC0002965
- Impending infarctionC0002965
- Impending infarction (disorder)C0002965
- Intermediate coronary syndromeC0002965
- Preinfarction AnginaC0002965
- Preinfarction AnginasC0002965
- Unstable AnginaC0002965
- Unstable Angina PectoriC0002965
- Unstable Angina PectorisC0002965
- Unstable AnginasC0002965
- Unstable anginaC0002965
- Worsening anginaC0002965
- angina at restC0002965
- angina unstableC0002965
- crescendo anginaC0002965
- impending infarctionC0002965
- intermediate coronary syndromeC0002965
- pre-infarction syndromeC0002965
- preinfarction anginaC0002965
- rest anginaC0002965
- unstable anginaC0002965
- unstable angina pectorisC0002965
- De novo effort anginaC1394765
- Myocardial Preinfarction SyndromeC0086666
- Myocardial Preinfarction SyndromesC0086666
- Pre infarction syndromeC0086666
- Pre-infarction syndromeC0086666
- Preinfarction Syndrome, MyocardialC0086666
- Preinfarction Syndromes, MyocardialC0086666
- Preinfarction anginaC0086666
- Preinfarction syndromeC0086666
- Preinfarction syndrome (disorder)C0086666
- Syndrome, Myocardial PreinfarctionC0086666
- Syndromes, Myocardial PreinfarctionC0086666
- Worsening effort anginaC2882088
Clinical Terms
- Myocardial Preinfarction Syndromes
- Chronic chest pain
- Preinfarction syndrome
- Preinfarction Syndrome, Myocardial
- Unstable Angina Pectori
- unstable angina pectoris
- crescendo angina
- Chronic ischaemic heart disease
- Accelerated angina
- preinfarction angina
- Angina control - worsening
- Angina Pectori, Unstable
- Preinfarction Syndromes, Myocardial
- Angina Pectoris, Unstable
- angina unstable
- Angina, Preinfarction
- Preinfarction Anginas
- Angina pectoris unstable
- Pre infarction syndrome
- Syndromes, Myocardial Preinfarction
- rest angina
- Preinfarction syndrome (disorder)
- Pre-infarction syndrome
- Chronic ischemic heart disease
- Angina at Rest
- Intermediate coronary syndrome
- Worsening effort angina
- impending infarction
- Progressive angina
- Impending infarction (disorder)
- Angina control
- De novo effort angina
- Anginas, Unstable
- Angina, Unstable
- Refractory angina
- Worsening angina
- Myocardial Preinfarction Syndrome
- Syndrome, Myocardial Preinfarction
- Anginas, Preinfarction
- Unstable Anginas
Frequently Asked Questions
What is the ICD-10 code for unstable angina?
The ICD-10-CM code for unstable angina is I20.0. The full clinical description is "Unstable angina". I20.0 is a billable/specific code that can be used on insurance claims and medical billing.
What does ICD-10 code I20.0 mean?
ICD-10-CM code I20.0 represents “Unstable angina”. It is classified under Chapter 9: Diseases of the Circulatory System and is a billable/specific code that can be used on a claim.
Is I20.0 a billable code?
Yes, I20.0 is a billable/specific ICD-10-CM code and can be used to indicate a diagnosis on a medical claim.
What chapter is I20.0 in?
I20.0 is in Chapter 9: Diseases of the Circulatory System (codes I00-I99).
What codes cannot be used with I20.0?
I20.0 has Excludes1 notes indicating codes that cannot be used together with it, including: angina pectoris with atherosclerotic heart disease of native coronary arteries (I25.1-); atherosclerosis of coronary artery bypass graft(s) and coronary artery of transplanted heart with angina pectoris (I25.7-); postinfarction angina (I23.7).
Are additional codes required with I20.0?
Yes, when using I20.0, also report: ; exposure to environmental tobacco smoke (Z77.22); history of tobacco dependence (Z87.891); occupational exposure to environmental tobacco smoke (Z57.31); tobacco dependence (F17.-); tobacco use (Z72.0).
What SNOMED CT codes does I20.0 map to?
I20.0 maps to 8 SNOMED CT concepts: 170593007, 170597008, 434011000124101, 413838009, 4557003, and 3 more. SNOMED CT is a clinical terminology used in electronic health records.
What are the UMLS CUIs for I20.0?
I20.0 is linked to 5 UMLS Concept Unique Identifiers: C2882087, C0002965, C1394765, C0086666, C2882088. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
How does I20.0 relate to ICF functioning codes?
ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like unstable angina affect a person's functioning — body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.
What is the ICD-11 equivalent of I20.0?
I20.0 maps to the ICD-11 code: BA40.0 (Unstable angina).
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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.