I27.0 Primary pulmonary hypertension

Billable ICD-10-CM code, FY2026. Acts as a Complication or Comorbidity (CC) as a secondary diagnosis.

Applicable to

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

Excludes1 (never code together)

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

Risk adjustment (HCC)

• CMS-HCC V28: HCC 226 — Heart Failure, Except End-Stage and Acute
• CMS-HCC V22: HCC 85 — Congestive Heart Failure
• RxHCC V08: HCC 183 — Pulmonary Arterial Hypertension
• ESRD V24: HCC 85

MS-DRG index

Defines the logic of DRG(s) 314-316 in MDC 05.

Approximate ICD-9-CM (GEMs)

• 416.0 Primary pulmonary hypertension

Code annotations containing back-references to I27.0

Back-references to I27.0

• Code First: I5A Non-ischemic myocardial injury (non-traumatic) ("pulmonary hypertension (I27.0, I27.2-)")
• Type 2 Excludes: I70 Atherosclerosis ("primary pulmonary atherosclerosis (I27.0)")

Diagnosis Index entries for I27.0

• Arrillaga-Ayerza syndrome (pulmonary sclerosis with pulmonary hypertension)
• Arteriosclerosis, arteriosclerotic (diffuse) (obliterans) (of) (senile) (with calcification) › pulmonary (idiopathic)
• Ayerza's disease or syndrome (pulmonary artery sclerosis with pulmonary hypertension)
• Cardiopathia nigra
• Disease, diseased › Ayerza's (pulmonary artery sclerosis with pulmonary hypertension)
• Disease, diseased › heart (organic) › black
• Disease, diseased › pulmonary › hypertensive (vascular) › primary (idiopathic)
• Hypertension, hypertensive (accelerated) (benign) (essential) (idiopathic) (malignant) (systemic) › lesser circulation
• Hypertension, hypertensive (accelerated) (benign) (essential) (idiopathic) (malignant) (systemic) › pulmonary › primary (idiopathic)
• Sclerosis, sclerotic › pulmonary › artery
• Syndrome › Arrillaga-Ayerza
• Syndrome › Ayerza (-Arrillaga)
• Syndrome › cardiacos negros
• Syndrome › pulmonary › arteriosclerosis

Nearby codes

• I27 Other pulmonary heart diseases
• I27.0 Primary pulmonary hypertension (this code)
• I27.1 Kyphoscoliotic heart disease
• I27.2 Other secondary pulmonary hypertension
• I27.20 Pulmonary hypertension, unspecified
• I27.21 Secondary pulmonary arterial hypertension
• I27.22 Pulmonary hypertension due to left heart disease