Is ICD-10-CM code I35 billable?

No, I35 (Nonrheumatic aortic valve disorders) is a non-billable ICD-10-CM code. It must be coded to a more specific subcategory before it can be used for reimbursement.

What chapter does ICD-10-CM code I35 belong to?

I35 belongs to Chapter 9 of the ICD-10-CM tabular list: I00–I99 (Diseases of the Circulatory System).

I35Not billable, use a more specific code below

Nonrheumatic aortic valve disorders

In Other forms of heart disease (I30-I5A), chapter 9: Diseases of the Circulatory System

5 billable codes under I35: none are a CC or MCC; none map to an HCC.

Instructional notes

Excludes2: not included here, code separately if applicable

aortic valve disorder of unspecified cause but with diseases of mitral and/or tricuspid valve(s) (I08.-)
aortic valve disorder specified as congenital (Q23.0, Q23.1)
aortic valve disorder specified as rheumatic (I06.-)
hypertrophic subaortic stenosis (I42.1)

Code also: add a code for this too, order depends on the encounter

if applicable, bicuspid aortic valve (Q23.81)

Official coding guidelines

From the ICD-10-CM Official Guidelines for Coding and Reporting, FY 2027 (CMS and NCHS). Links open the PDF at the right page.

Covers hypertension with heart and kidney disease, coronary artery disease with angina, perioperative stroke, cerebrovascular sequelae, and acute myocardial infarction types and timing.

Hypertension (page 50)
Atherosclerotic Coronary Artery Disease and Angina (page 52)
Intraoperative and Postprocedural Cerebrovascular Accident (page 53)
Sequelae of Cerebrovascular Disease (page 53)
Acute myocardial infarction (AMI) (page 54)

Read Section I.C.9 (page 50)

All codes under I35

I35 can't be used on a claim. Pick a billable code below; grey headings group them.

I35 MS-DRGs

As the principal diagnosis, all 5 billable codes under I35 group to MS-DRG 306 or 307 (v44.0). Which one applies depends on procedures performed, secondary diagnoses (CC/MCC), and the patient's age and discharge status.

Other codes that refer to I35

Notes on these codes point to I35.

I06 Excludes2: aortic valve disease not specified as rheumatic (I35.-)
I08 Excludes2: multiple valve disease specified as nonrheumatic (I34.-, I35.-, I36.-, I37.-, I38.-, Q22.-, Q23.-, Q24.8-)
I5A Code First: nonrheumatic aortic valve disorders (I35.-)

About the condition

Plain-language background from MedlinePlus (National Library of Medicine), not coding guidance.

Heart Valve Diseases

Heart valve disease happens when one or more of your heart valves don't work well. Your heart has four valves: the tricuspid, pulmonary, mitral, and aortic valves. The valves have flaps that open and close. The flaps make sure that blood flows in the right direction through your heart and to the rest of your body. When your heart beats, the flaps open to let blood through. Between heartbeats they close to stop the blood from flowing backwards.

Code history

Valid since FY2016, when ICD-10-CM took effect on October 1, 2015. No changes since.