I ICD-10-CM Categories: Category Index
Browse 80 top-level ICD-10-CM categories beginning with I, then follow their complete FY 2027 child-code hierarchies.
Categories beginning with I
Open a category to continue through its complete hierarchy of more specific codes.
I00Rheumatic fever without heart involvementI01Rheumatic fever with heart involvementI02Rheumatic choreaI05Rheumatic mitral valve diseasesI06Rheumatic aortic valve diseasesI07Rheumatic tricuspid valve diseasesI08Multiple valve diseasesI09Other rheumatic heart diseasesI10Essential (primary) hypertensionI11Hypertensive heart diseaseI12Hypertensive chronic kidney diseaseI13Hypertensive heart and chronic kidney diseaseI15Secondary hypertensionI16Hypertensive crisisI1AOther hypertensionI20Angina pectorisI21Acute myocardial infarctionI22Subsequent ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarctionI23Certain current complications following ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarction (within the 28 day period)I24Other acute ischemic heart diseasesI25Chronic ischemic heart diseaseI26Pulmonary embolismI27Other pulmonary heart diseasesI28Other diseases of pulmonary vesselsI30Acute pericarditisI31Other diseases of pericardiumI32Pericarditis in diseases classified elsewhereI33Acute and subacute endocarditisI34Nonrheumatic mitral valve disordersI35Nonrheumatic aortic valve disordersI36Nonrheumatic tricuspid valve disordersI37Nonrheumatic pulmonary valve disordersI38Endocarditis, valve unspecifiedI39Endocarditis and heart valve disorders in diseases classified elsewhereI40Acute myocarditisI41Myocarditis in diseases classified elsewhereI42CardiomyopathyI43Cardiomyopathy in diseases classified elsewhereI44Atrioventricular and left bundle-branch blockI45Other conduction disordersI46Cardiac arrestI47Paroxysmal tachycardiaI48Atrial fibrillation and flutterI49Other cardiac arrhythmiasI50Heart failureI51Complications and ill-defined descriptions of heart diseaseI52Other heart disorders in diseases classified elsewhereI5ANon-ischemic myocardial injury (non-traumatic)I60Nontraumatic subarachnoid hemorrhageI61Nontraumatic intracerebral hemorrhageI62Other and unspecified nontraumatic intracranial hemorrhageI63Cerebral infarctionI65Occlusion and stenosis of precerebral arteries, not resulting in cerebral infarctionI66Occlusion and stenosis of cerebral arteries, not resulting in cerebral infarctionI67Other cerebrovascular diseasesI68Cerebrovascular disorders in diseases classified elsewhereI69Sequelae of cerebrovascular diseaseI70AtherosclerosisI71Aortic aneurysm and dissectionI72Other aneurysmI73Other peripheral vascular diseasesI74Arterial embolism and thrombosisI75AtheroembolismI76Septic arterial embolismI77Other disorders of arteries and arteriolesI78Diseases of capillariesI79Disorders of arteries, arterioles and capillaries in diseases classified elsewhereI80Phlebitis and thrombophlebitisI81Portal vein thrombosisI82Other venous embolism and thrombosisI83Varicose veins of lower extremitiesI85Esophageal varicesI86Varicose veins of other sitesI87Other disorders of veinsI88Nonspecific lymphadenitisI89Other noninfective disorders of lymphatic vessels and lymph nodesI95HypotensionI96Gangrene, not elsewhere classifiedI97Intraoperative and postprocedural complications and disorders of circulatory system, not elsewhere classifiedI99Other and unspecified disorders of circulatory systemSource and release
- Data release
- U.S. ICD-10-CM · FY 2027
- Effective date
- Oct 1, 2026
- Publisher
- Vero Scribe Inc.
This category index is generated from Vero’s repository-backed ICD-10-CM hierarchy. Every listed category is a top-level record, and each linked category page exposes its direct child codes.
Frequently asked questions
Which ICD-10-CM categories begin with I?
This index lists 80 top-level categories beginning with I from Vero’s FY 2027 U.S. ICD-10-CM reference dataset.
How do I find a more specific I code?
Open a category below, then follow its linked child-code hierarchy until you reach the code supported by the documentation.
Which ICD-10-CM release does this I index use?
The index uses the FY 2027 U.S. ICD-10-CM release and the repository-backed hierarchy displayed on each linked code page.
Is every I category billable?
No. These are top-level categories used for navigation. Follow the hierarchy to a sufficiently specific code and confirm the active code set, official guidance, and payer requirements.