I27.21
Billable codeSecondary pulmonary arterial hypertension
The ICD-10 code for secondary pulmonary arterial hypertension is I27.21.
Clinical notes
Code also
Two codes may be needed to fully describe a condition, but unlike Code First/Use Additional Code, the sequencing order is not mandated by convention.
- associated conditions if applicable, or adverse effects of drugs or toxins, such as:
- adverse effect of appetite depressants (T50.5X5)
- congenital heart disease (Q20-Q28)
- human immunodeficiency virus [HIV] disease (B20)
- polymyositis (M33.2-)
- portal hypertension (K76.6)
- rheumatoid arthritis (M05.-)
- schistosomiasis (B65.-)
- Sjögren syndrome (M35.0-)
- systemic sclerosis (M34.-)
Also known as
Alternate wording, synonyms, or specific conditions that fall under this code, listed to help confirm you've picked the right one.
- (Associated) (drug-induced) (toxin-induced) pulmonary arterial hypertension NOS
- (Associated) (drug-induced) (toxin-induced) (secondary) group 1 pulmonary hypertension
Documentation support
General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.
- •Laterality-specific codes exist for this condition — confirm the affected side is documented.
- •As a general rule, code to the highest level of specificity supported by the documentation in the medical record.
Related codes in this category
ICD-9-CM equivalent
Informational only — GEM mappings are approximate, not guaranteed one-to-one equivalents. Verify before use in billing.
- 4168Approximate match
Associated MS-DRGs
I27.21 can serve as the principal diagnosis for these Medicare Severity Diagnosis-Related Groups.
Informational only — actual DRG assignment also depends on procedures, complications/comorbidities (CC/MCC), discharge status, and payer-specific rules not reflected here.