2027 ICD-10-CM Diagnosis Code I99.8Other disorder of circulatory system

ICD-10-CM Codes›I00–I99›I95-I99›I99

ICD-10-CM I99.8
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

I99.8 is a billable ICD-10-CM diagnosis code for other disorder of circulatory system. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 302 through 303. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified circulatory disease.

Code Identity

ICD-10-CM Code
I99.8
Billable Status
Yes — Valid for Submission
Code Describes
Other disorder of circulatory system
Short Description
Other disorder of circulatory system
Same as the full description in the CMS dataset.
Parent Code
I99
Other and unspecified disorders of circulatory system

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI95-I99Other and unspecified disorders of the circulatory system
CategoryI99Other and unspecified disorders of circulatory system
This CodeI99.8Other disorder of circulatory system

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Abnormality of hepatic vein
  • Acquired arteriovenous malformation
  • Acquired arteriovenous malformation of vascular structure of gastrointestinal tract
  • Acute ischemic pancreatitis
  • Acute lower limb ischemia
  • Acute vascular insufficiency
  • Acute visceral ischemia
  • Alteration in tissue perfusion
  • Arterial ischemia
  • Arteriovenous fistula occlusion
  • Arteriovenous fistula rupture
  • Arteriovenous graft occlusion
  • Arteriovenous shunt occlusion
  • Bacterial cardiovascular infection
  • Brown-Séquard syndrome due to ischemia
  • Calcinosis following arterial/venous infarct
  • Cardiovascular fistula due to endocarditis
  • Cardiovascular morbidity
  • Cardiovascular system hereditary disorder
  • Chronic disease of cardiovascular system
  • Chronic vascular insufficiency
  • Complement hyperactivation, angiopathic thrombosis, protein losing enteropathy syndrome
  • Congenital critical stenosis of aortic valve with ductus arteriosus dependent systemic circulation
  • Congenital stenosis of aortic valve
  • Contusion of skin due to vascular fragility
  • Critical ischemia of foot
  • Critical lower limb ischemia
  • Critical stenosis of aortic valve
  • Cushing phenomenon
  • Decay accelerating factor deficiency
  • Dehiscence of aortic valve annulus as complication of procedure
  • Dermatosis resulting from small vessel insufficiency
  • Dilated blood vessels in skin
  • Disorder of arteriovenous shunt
  • Disorder of oxygen transport
  • Disorder of portal venous system
  • Disruption of aortic valve annulus
  • Ductus arteriosus dependent systemic circulation
  • Entrapment of blood vessel
  • Flap ischemia
  • Fragile blood vessel
  • Fungal cardiovascular infection
  • Gaucher disease with ophthalmoplegia and cardiovascular calcification
  • Gaucher's disease
  • Graft failure due to prolonged ischemia
  • Hereditary cutaneous vascular syndrome
  • Hereditary dysplasia of blood vessel
  • Hypostasis
  • Impairment of peripheral tissue perfusion
  • Inadequate flow to support prescribed dialysis blood flow
  • Increased capillary fragility
  • Ineffective tissue perfusion
  • Ischemia
  • Ischemia of bilateral lower limbs
  • Ischemia of bilateral upper limbs
  • Ischemia of left lower extremity
  • Ischemia of left upper limb
  • Ischemia of right lower extremity
  • Ischemia of right upper limb
  • Ischemia of stoma
  • Ischemic anterior cord syndrome
  • Ischemic finger
  • Ischemic foot
  • Ischemic hand
  • Ischemic pancreatitis
  • Ischemic reperfusion injury
  • Ischemic toe
  • Limb ischemia
  • Lower limb ischemia
  • Mass of cardiovascular structure
  • Obstruction of surgically constructed systemic venous pathway as complication of procedure
  • Occlusion of microvasculature of skin caused by platelet plug
  • Pain of bilateral lower limbs co-occurrent and due to ischemia
  • Pain of bilateral upper limbs co-occurrent and due to ischemia
  • Pain of left lower limb co-occurrent and due to ischemia
  • Pain of left upper limb co-occurrent and due to ischemia
  • Pain of right lower limb co-occurrent and due to ischemia
  • Peripheral ischemia
  • Protein-losing enteropathy
  • Purpura due to increased intravascular pressure
  • Retinal arteriovenous dilatation
  • Right upper limb pain co-occurrent and due to ischemia
  • Subacute neuronopathic Gaucher's disease
  • Thrombophilia due to vascular anomaly
  • Transient ischemia
  • Upper limb ischemia
  • Vascular calcification
  • Vascular disorder of spine
  • Vascular graft calcification
  • Vascular graft occlusion
  • Vascular insufficiency
  • Venous collateral circulation
  • Viral cardiovascular infection
  • Visceral ischemia

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to I99.8: its own notes plus those printed at Chapter 9. A note printed at a category, block or chapter applies to every code under it.

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 9 (I00-I99) Diseases of the circulatory system applies to 1,433 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
  • systemic connective tissue disorders (M30-M36)
  • transient cerebral ischemic attacks and related syndromes (G45.-)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR CIR032
Other specified and unspecified circulatory disease
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Ischemia

    a hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation.

Convert I99.8 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
459.89 Circulatory disease NEC
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About I99.8Overview

What is the ICD-10 code for other disorder of circulatory system?

The ICD-10-CM code for other disorder of circulatory system is I99.8 (sometimes written as I998). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is I99.8 (Other and unspecified disorders of circulatory system) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other disorder of circulatory system on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does I99.8 group to?

When other disorder of circulatory system is the principal diagnosis on an inpatient stay, it groups to MS-DRG 302, 303, with relative weights from 0.6610 to 1.1993 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of I99.8?

Under the General Equivalence Mappings, other disorder of circulatory system converts to ICD-9-CM 459.89 (circulatory disease NEC). The mapping is approximate, so confirm the match fits the documentation.