2026 ICD-10-CM Diagnosis Code I27.29Other secondary pulmonary hypertension

ICD-10-CM Codes›I00–I99›I26-I28›I27

ICD-10-CM I27.29
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

I27.29 is a billable ICD-10-CM diagnosis code for other secondary pulmonary hypertension. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 314 through 316. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Pulmonary heart disease.

For Medicare Advantage risk adjustment, I27.29 maps to CMS-HCC Category 226 (Heart Failure, Except End Stage and Acute) under the V28 model, adding a risk factor of about 0.360 for a community, non-dual, aged beneficiary in payment year 2026.

This medical diagnosis code is frequently used in Cardiology medical specialties to designate conditions such hypertension.

Code Identity

ICD-10-CM Code
I27.29
Billable Status
Yes — Valid for Submission
Code Describes
Other secondary pulmonary hypertension
Short Description
Other secondary pulmonary hypertension
Same as the full description in the CMS dataset.
Parent Code
Other secondary pulmonary hypertension

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI26-I28Pulmonary heart disease and diseases of pulmonary circulation
CategoryI27Other pulmonary heart diseases
This CodeI27.29Other secondary pulmonary hypertension

Medicare Risk Adjustment (HCC)Billing

I27.29 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2026.

CMS-HCC V28 Category (Payment Model)
HCC 226— Heart Failure, Except End Stage and Acute
Payment HCC · PY 2026 one of 34 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.360
community, non-dual, aged · ranges 0.217–0.537 across segments
Hierarchy
Superseded by HCC 221, HCC 222, HCC 223, HCC 224, and HCC 225
a more severe related category takes the payment when both are reported
Prior Model (CMS-HCC V24)
HCC 85
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 85 · ESRD (V21): HCC 85 · ESRD (V24): HCC 85
ESRD V21 weights: 0.082 dialysis, 0.186–0.336 functioning graft · ESRD V24 weights: 0.063 dialysis, 0.169–0.302 functioning graft
Part D (RxHCC)
RxHCC 184 — Pulmonary Hypertension, Except Arterial, and Other Pulmonary Heart Disease
also risk-adjusts in the Part D prescription drug model (V08)

Source: CMS Payment Year 2026 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Associated pulmonary arterial hypertension
  • Effects of air pressure
  • Facultative pulmonary hypertension with shunt at atrial level
  • Large vessel pulmonary hypertension
  • Post-arteritic pulmonary hypertension
  • Postcapillary pulmonary hypertension
  • Pulmonary arterial hypertension associated with portal hypertension
  • Pulmonary hypertension associated with chronic underventilation
  • Pulmonary hypertension caused by low air pressure due to chronic exposure to high altitude
  • Pulmonary hypertension due to alveolar hypoventilation disorder
  • Pulmonary hypertension due to developmental abnormality
  • Pulmonary hypertension due to diastolic systemic ventricular dysfunction
  • Pulmonary hypertension due to hematological disorder
  • Pulmonary hypertension due to left heart disease
  • Pulmonary hypertension due to left-sided valvular heart disease
  • Pulmonary hypertension due to lung disease and/or hypoxia
  • Pulmonary hypertension due to myeloproliferative disorder
  • Pulmonary hypertension due to post-splenectomy hematological disorder
  • Pulmonary hypertension due to sleep-disordered breathing
  • Pulmonary hypertension due to vasculitis
  • Pulmonary hypertension in Langerhans cell histiocytosis
  • Pulmonary hypertension in neurofibromatosis
  • Pulmonary hypertension in sarcoidosis
  • Pulmonary hypertension in systemic disorder
  • Pulmonary hypertension secondary to raised pulmonary vascular resistance
  • Pulmonary hypertension with extreme obesity
  • Pulmonary hypertension with occult mitral stenosis
  • Pulmonary veno-occlusive disease
  • Pulmonary venous hypertension as complication of procedure
  • Pulmonary venous hypertension due to compression of pulmonary great vein
  • Pulmonary venous hypertension due to compression of pulmonary great vein by lymphadenopathy
  • Pulmonary venous hypertension due to compression of pulmonary great vein by neoplasm
  • Pulmonary venous hypertension due to compression of pulmonary great vein by sclerosing mediastinitis
  • Pulmonary venous hypertension due to congenital stenosis of pulmonary vein
  • Small vessel pulmonary hypertension
  • Solitary pulmonary hypertension

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Group 5 pulmonary hypertension
  • Pulmonary hypertension with unclear multifactorial mechanisms
  • Pulmonary hypertension due to hematologic disorders
  • Pulmonary hypertension due to metabolic disorders
  • Pulmonary hypertension due to other systemic disorders

Code Also

  • other associated disorders, if known, such as:
  • chronic myeloid leukemia C92.10 C92.22
  • essential thrombocythemia D47.3
  • Gaucher disease E75.22
  • hypertensive chronic kidney disease with end stage renal disease I12.0 I13.11 I13.2
  • hyperthyroidism E05
  • hypothyroidism E00 E03
  • polycythemia vera D45
  • sarcoidosis D86

Index to Diseases and InjuriesGuidance

Clinical ClassificationClinical

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

CCSR CIR014
Pulmonary heart disease
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Pulmonary Hypertension

Pulmonary hypertension, sometimes called PH, is a serious condition that affects the blood vessels in the lungs. It develops when the blood pressure in your lungs is higher than normal.

The full article covers:

  • What is pulmonary hypertension?
  • What causes pulmonary hypertension?
  • Who is more likely to develop pulmonary hypertension?
  • What are the symptoms of pulmonary hypertension?
  • What other problems can pulmonary hypertension cause?
  • How is pulmonary hypertension diagnosed?
  • What are the treatments for pulmonary hypertension?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert I27.29 to ICD-9-CMHistory

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

ICD-9-CM
416.8 Chr pulmon heart dis NEC
Approximate The match is approximate rather than exact.

Code History & ChangesHistory

Replacement I27.29 replaces the following previously assigned code(s):

  • I27.2 - Other secondary pulmonary hypertension
FY 2019AddedAdded to the ICD-10-CM code setEffective October 1, 2018.
FY 2020–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About I27.29Overview

What is the ICD-10 code for other secondary pulmonary hypertension?

The ICD-10-CM code for other secondary pulmonary hypertension is I27.29 (sometimes written as I2729). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is I27.29 (Other secondary pulmonary hypertension) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other secondary pulmonary hypertension on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does I27.29 group to?

When other secondary pulmonary hypertension is the principal diagnosis on an inpatient stay, it groups to MS-DRG 314, 315, 316, with relative weights from 0.6821 to 2.0852 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of I27.29?

Under the General Equivalence Mappings, other secondary pulmonary hypertension converts to ICD-9-CM 416.8 (chr pulmon heart dis NEC). The mapping is approximate, so confirm the match fits the documentation.

What HCC is I27.29?

I27.29 (other secondary pulmonary hypertension) maps to CMS-HCC Category 226 (Heart Failure, Except End Stage and Acute), commonly written as HCC 226, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2026. It mapped to HCC 85 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 184.

Does I27.29 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, I27.29 adds a risk adjustment factor of about 0.360 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.217 to 0.537 depending on the payment segment). A more severe related category (HCC 221, HCC 222, HCC 223, HCC 224, and HCC 225) supersedes it when both are reported. See the full factor table on the HCC 226 category page.