2025 ICD-10-CM Diagnosis Code I27.0

Primary pulmonary hypertension

• I27.0 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
• The 2025 edition of ICD-10-CM I27.0 became effective on October 1, 2024.
• This is the American ICD-10-CM version of I27.0 – other international versions of ICD-10 I27.0 may differ.

Applicable To

• Heritable pulmonary arterial hypertension
• Idiopathic pulmonary arterial hypertension
• Primary group 1 pulmonary hypertension
• Primary pulmonary arterial hypertension

Type 1 Excludes

• persistent pulmonary hypertension of newborn (P29.30)
• pulmonary hypertension NOS (I27.20)
• secondary pulmonary arterial hypertension (I27.21)
• secondary pulmonary hypertension (I27.29)

The following code(s) above I27.0 contain annotation back-references

 that may be applicable to I27.0:

• I00-I99  Diseases of the circulatory system

Approximate Synonyms

• Ayerza’s syndrome
• Ayerzas syndrome
• Idiopathic pulmonary arterial hypertension

Clinical Information

• Increased blood pressure in the arteries of the lungs; the etiology is unknown.

ICD-10-CM I27.0 is grouped within Diagnostic Related Group(s) (MS-DRG v42.0):

• 314 Other circulatory system diagnoses with mcc
• 315 Other circulatory system diagnoses with cc
• 316 Other circulatory system diagnoses without cc/mcc

Convert I27.0 to ICD-9-CMCode History

• 2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
• 2017 (effective 10/1/2016): No change
• 2018 (effective 10/1/2017): No change
• 2019 (effective 10/1/2018): No change
• 2020 (effective 10/1/2019): No change
• 2021 (effective 10/1/2020): No change
• 2022 (effective 10/1/2021): No change
• 2023 (effective 10/1/2022): No change
• 2024 (effective 10/1/2023): No change
• 2025 (effective 10/1/2024): No change

Code annotations containing back-references to I27.0:

• Code First: I5A
• Type 2 Excludes: I70

Diagnosis Index entries containing back-references to I27.0:

• Arrillaga-Ayerza syndrome I27.0 (pulmonary sclerosis with pulmonary hypertension)
• Arteriosclerosis, arteriosclerotic (diffuse) (obliterans) (of) (senile) (with calcification) I70.90
  • pulmonary I27.0 (idiopathic)
• Ayerza’s disease or syndrome I27.0 (pulmonary artery sclerosis with pulmonary hypertension)
• Cardiopathia nigra I27.0
• Disease, diseased – see also Syndrome
  • heart (organic) I51.9
    • black I27.0
  • pulmonary – see also Disease, lung
    • hypertensive (vascular) I27.20 – see also Hypertension, pulmonary
      • primary I27.0 (idiopathic)
  • Ayerza’s I27.0 (pulmonary artery sclerosis with pulmonary hypertension)
• Hypertension, hypertensive (accelerated) (benign) (essential) (idiopathic) (malignant) (systemic) I10
  • pulmonaryI27.20
    • primary I27.0 (idiopathic)
  • lesser circulation I27.0
• Sclerosis, sclerotic
  • pulmonary – see Fibrosis, lung
    • artery I27.0
• Syndrome – see also Disease
  • pulmonary
    • arteriosclerosis I27.0
  • Arrillaga-Ayerza I27.0
  • Ayerza I27.0 (-Arrillaga)
  • cardiacos negros I27.0