ICD10BillableValid for clinical use
ICD-10 Code I27.0: Primary pulmonary hypertension
Reviewed by HealthAssure Clinical TeamUpdated 26 May 2026
What is this code?
ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Diseases of the circulatory system (I00-I99).
đź“‹Clinical overview
This ICD-10 code is commonly used when documentation describes pulmonary hypertension. The most accurate code depends on whether the condition is primary or secondary and whether the chart identifies a left-heart, lung-and-hypoxia, chronic-thromboembolic, or other driving mechanism.
When is it used?
- May be used when a clinician documents primary pulmonary hypertension in a patient's medical record.
- May appear in hospital records, claims, referrals, and clinical documentation.
- This code can be used as a clinically usable diagnosis entry in standardized coding workflows.
What it does not mean
- A code alone does not explain severity, treatment plan, or outcome.
- A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
đź©şClinical context
When commonly used
- Cardiology, pulmonology, inpatient, and utilization-review workflows where pulmonary hypertension affects evaluation, treatment planning, or chronic disease follow-up.
- Coding workflows where the chart identifies primary versus secondary pulmonary hypertension or names the underlying mechanism that changes final code specificity.
Common management context
- Evaluation often includes echocardiography, cardiopulmonary assessment, imaging review, hemodynamic context, and follow-up of the underlying heart, lung, or thromboembolic condition.
- Documentation usually becomes more specific when the chart identifies primary pulmonary hypertension, secondary pulmonary arterial hypertension, left-heart-disease association, lung-disease or hypoxia association, chronic thromboembolic disease, or another secondary pattern.
- Specialist context already linked on this page includes Cardiologist, General Physician.
🔍Key distinctions
Important notes
- This ICD-10 family captures pulmonary-hypertension diagnoses rather than systemic hypertension or unrelated pulmonary disorders without pulmonary-hypertension context.
- Primary versus secondary disease and the documented underlying mechanism both affect final code specificity inside this family.
- Primary pulmonary hypertension is coded separately from the secondary pulmonary-hypertension branches when the chart clearly documents that distinction.
Important exclusions
- persistent pulmonary hypertension of newborn (P29.30)
- pulmonary hypertension NOS (I27.20)
- secondary pulmonary arterial hypertension (I27.21)
- secondary pulmonary hypertension (I27.29)
Related codes to consider
I27.1Kyphoscoliotic heart disease
Related pulmonary-hypertension ICD-10 code; documentation often becomes more specific when the chart identifies primary versus secondary disease or names the heart, lung, hypoxia, or thromboembolic mechanism.
I27.2Other secondary pulmonary hypertension
Related pulmonary-hypertension ICD-10 code; documentation often becomes more specific when the chart identifies primary versus secondary disease or names the heart, lung, hypoxia, or thromboembolic mechanism.
I27.8Other specified pulmonary heart diseases
Related pulmonary-hypertension ICD-10 code; documentation often becomes more specific when the chart identifies primary versus secondary disease or names the heart, lung, hypoxia, or thromboembolic mechanism.
I27.9Pulmonary heart disease, unspecified
Related pulmonary-hypertension ICD-10 code; documentation often becomes more specific when the chart identifies primary versus secondary disease or names the heart, lung, hypoxia, or thromboembolic mechanism.
Code hierarchy
chapter
9Diseases of the circulatory system (I00-I99)
block
I26-I28Pulmonary heart disease and diseases of pulmonary circulation
category
I27Other pulmonary heart diseases
currentI27
Official coding notes
Inclusion terms
- Heritable pulmonary arterial hypertension
- Idiopathic pulmonary arterial hypertension
- Primary group 1 pulmonary hypertension
- Primary pulmonary arterial hypertension
Excludes1 (do not 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)
Where you may see this code
You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records.
Related specialists
CardiologistGeneral Physician
Related codes
Sibling codes
Coverage-related procedures and services
CPT 93350high
ECHOCARDIOGRAPHY, TRANSTHORACIC, REAL-TIME WITH IMAGE DOCUMENTATION (2D), INCLUDES M-MODE RECORDING, WHEN PERFORMED, DURING REST AND CARDIOVASCULAR STRESS TEST USING TREADMILL, BICYCLE EXERCISE AND/OR PHARMACOLOGICALLY INDUCED STRESS, WITH INTERPRETATION AND REPORT;
Source: CMS coverage guidance
CPT 93351high
ECHOCARDIOGRAPHY, TRANSTHORACIC, REAL-TIME WITH IMAGE DOCUMENTATION (2D), INCLUDES M-MODE RECORDING, WHEN PERFORMED, DURING REST AND CARDIOVASCULAR STRESS TEST USING TREADMILL, BICYCLE EXERCISE AND/OR PHARMACOLOGICALLY INDUCED STRESS, WITH INTERPRETATION AND REPORT; INCLUDING PERFORMANCE OF CONTINUOUS ELECTROCARDIOGRAPHIC MONITORING, WITH SUPERVISION BY A PHYSICIAN OR OTHER QUALIFIED HEALTH CARE PROFESSIONAL
Source: CMS coverage guidance
CPT 93352high
USE OF ECHOCARDIOGRAPHIC CONTRAST AGENT DURING STRESS ECHOCARDIOGRAPHY (LIST SEPARATELY IN ADDITION TO CODE FOR PRIMARY PROCEDURE)
Source: CMS coverage guidance
CPT 75574high
COMPUTED TOMOGRAPHIC ANGIOGRAPHY, HEART, CORONARY ARTERIES AND BYPASS GRAFTS (WHEN PRESENT), WITH CONTRAST MATERIAL, INCLUDING 3D IMAGE POSTPROCESSING (INCLUDING EVALUATION OF CARDIAC STRUCTURE AND MORPHOLOGY, ASSESSMENT OF CARDIAC FUNCTION, AND EVALUATION OF VENOUS STRUCTURES, IF PERFORMED)
Source: CMS coverage guidance
CPT 75572high
COMPUTED TOMOGRAPHY, HEART, WITH CONTRAST MATERIAL, FOR EVALUATION OF CARDIAC STRUCTURE AND MORPHOLOGY (INCLUDING 3D IMAGE POSTPROCESSING, ASSESSMENT OF CARDIAC FUNCTION, AND EVALUATION OF VENOUS STRUCTURES, IF PERFORMED)
Source: CMS coverage guidance
CPT 75573high
COMPUTED TOMOGRAPHY, HEART, WITH CONTRAST MATERIAL, FOR EVALUATION OF CARDIAC STRUCTURE AND MORPHOLOGY IN THE SETTING OF CONGENITAL HEART DISEASE (INCLUDING 3D IMAGE POSTPROCESSING, ASSESSMENT OF LEFT VENTRICULAR [LV] CARDIAC FUNCTION, RIGHT VENTRICULAR [RV] STRUCTURE AND FUNCTION AND EVALUATION OF VASCULAR STRUCTURES, IF PERFORMED)
Source: CMS coverage guidance
Mapped diagnoses and classifications
SNOMED_CT 78862003high
Ayerza's syndrome
Source: SNOMED International ICD-10 map
SNOMED_CT 87394009high
Episodic pulmonary hypertension
Source: SNOMED International ICD-10 map
SNOMED_CT 233944003high
Familial primary pulmonary hypertension
Source: SNOMED International ICD-10 map
SNOMED_CT 697897003high
Heritable pulmonary arterial hypertension
Source: SNOMED International ICD-10 map
SNOMED_CT 697900005high
Heritable pulmonary arterial hypertension due to ALK1 or endoglin mutation
Source: SNOMED International ICD-10 map
SNOMED_CT 697899000high
Heritable pulmonary arterial hypertension due to BMPR2 mutation
Source: SNOMED International ICD-10 map
Coding guidelines
Compatibility
Legacy and official ICD code match exactly.
Legacy codes
I27.0
Common synonyms
Primary pulmonary hypertension
Frequently asked questions
About this content
This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.