2026 ICD-10-CM Diagnosis Code I50.9Heart failure, unspecified
ICD-10-CM Codes›I00–I99›I30-I5A›I50
- Billable — Valid for Submission
- Chronic Condition
I50.9 is a billable ICD-10-CM diagnosis code for heart failure, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 291 through 293. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Heart failure.
This medical diagnosis code is frequently used in Cardiology medical specialties to designate conditions such heart failure.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Acute congestive heart failure
- Acute exacerbation of chronic congestive heart failure
- Acute exacerbation of chronic heart failure
- Acute heart failure
- Acute heart failure co-occurrent with normal ejection fraction
- Acute on chronic heart failure co-occurrent with normal ejection fraction
- Benign hypertensive heart disease
- Benign hypertensive heart disease with congestive cardiac failure
- Cardiac arrest AND/OR failure following anesthesia AND/OR sedation in labor AND/OR delivery
- Cardiac arrest due to procedure
- Cardiac arrest during procedure
- Cardiac arrest following obstetric procedure
- Cardiac arrhythmia during pregnancy
- Cardiac edema
- Cardiac insufficiency during AND/OR resulting from a procedure
- Cardiac insufficiency following cardiac surgery
- Cardiorenal syndrome
- Chronic congestive heart failure
- Chronic heart failure
- Chronic heart failure co-occurrent with normal ejection fraction
- Compensated cardiac failure
- Complication due to cardiac conduit operation
- Congestive heart failure
- Congestive heart failure as early postoperative complication
- Congestive heart failure as post-operative complication of cardiac surgery
- Congestive heart failure as post-operative complication of non-cardiac surgery
- Congestive heart failure due to cardiomyopathy
- Congestive heart failure due to valvular disease
- Congestive heart failure stage B
- Congestive heart failure stage B due to ischemic cardiomyopathy
- Congestive heart failure stage C
- Congestive heart failure stage C due to ischemic cardiomyopathy
- Congestive heart failure stage D
- Congestive rheumatic heart failure
- Decompensated cardiac failure
- Decompensated chronic heart failure
- Diastolic dysfunction
- Disorder confirmed
- Exacerbation of congestive heart failure
- Heart disease due to thyrotoxicosis
- Heart failure
- Heart failure confirmed
- Heart failure due to end stage congenital heart disease
- Heart failure due to thyrotoxicosis
- Heart failure following administration of antineoplastic agent
- Heart failure following obstetric procedure
- Heart failure with normal ejection fraction
- Heart failure with reduced ejection fraction
- Heart failure with reduced ejection fraction due to cardiomyopathy
- Heart failure with reduced ejection fraction due to coronary artery disease
- Heart failure with reduced ejection fraction due to heart valve disease
- Heart failure with reduced ejection fraction due to myocarditis
- Hypertensive heart AND chronic kidney disease with congestive heart failure
- Hypertensive heart and renal disease with heart failure
- Hypertensive heart and renal disease with both heart failure and renal failure
- Hypertensive heart disease with congestive heart failure
- Hypertensive heart failure
- Hypertensive renal failure
- Low cardiac output syndrome
- Low output heart failure
- Low output heart failure due to and following Fontan operation
- Malignant hypertensive heart disease
- Malignant hypertensive heart disease with congestive heart failure
- Nail changes associated with systemic disease
- Normal cardiac ejection fraction
- Normal cardiac function
- Obstetrical cardiac complication of anesthesia AND/OR sedation
- Obstetrical complication of anesthesia AND/OR sedation
- Pleural effusion due to another disorder
- Pleural effusion due to congestive heart failure
- Red half-moon nail in congestive heart failure
- Refractory heart failure
- Symptomatic congestive heart failure
- X-linked intellectual disability, cardiomegaly, congestive heart failure syndrome
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Cardiac, heart or myocardial failure NOS
- Congestive heart disease
- Congestive heart failure NOS
Type 2 Excludes
- fluid overload unrelated to congestive heart failure E87.70
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
- cardiac - See Also: Failure, heart; - I50.9
- cardiovascular - See Also: Failure, heart; - I50.9
- heart - See Also: Failure, heart; - I50.9
- myocardial - See Also: Failure, heart; - I50.9
- ventricular - I51.9
- with congestive heart failure - See Also: Failure, heart; - I50.9
- cardiorenal (chronic) - See Also: Failure, renal, and Failure, heart; - I50.9
- heart (acute) (senile) (sudden) - I50.9
- with
- decompensation - I50.9
- compensated - See Also: Failure, heart, by type as diastolic or systolic, chronic; - I50.9
- congestive - I50.9
- decompensated - See Also: Failure, heart, by type as diastolic or systolic, acute and chronic; - I50.9
- low output (syndrome) NOS - I50.9
- myocardial, myocardium - See Also: Failure, heart; - I50.9
- chronic - See Also: Failure, heart, congestive; - I50.9
- congestive - See Also: Failure, heart, congestive; - I50.9
- ventricular - See Also: Failure, heart; - I50.9
- myocardial, myocardium (with arteriosclerosis) - See Also: Failure, heart; - I50.9
- Paralysis, paralytic (complete) (incomplete) - G83.9
- cardiac - See Also: Failure, heart; - I50.9
- Syndrome - See Also: Disease;
- low
- output (cardiac) - I50.9
External Cause of Injuries IndexGuidance
References for this code in the External Cause of Injuries Index.
- Asthenia, asthenic
- cardiac
- Asthenia, asthenic
- cardiovascular
- Asthenia, asthenic
- heart
- Asthenia, asthenic
- myocardial
- Dysfunction
- ventricular
- with congestive heart failure
- Failure, failed
- cardiorenal (chronic)
- Failure, failed
- heart (acute) (senile) (sudden)
- Failure, failed
- heart (acute) (senile) (sudden)
- with
- decompensation
- Failure, failed
- heart (acute) (senile) (sudden)
- compensated
- Failure, failed
- heart (acute) (senile) (sudden)
- congestive
- Failure, failed
- heart (acute) (senile) (sudden)
- decompensated
- Failure, failed
- heart (acute) (senile) (sudden)
- low output (syndrome) NOS
- Failure, failed
- Note
- stage B
- Failure, failed
- Note
- stage C
- Failure, failed
- myocardial, myocardium
- Failure, failed
- myocardial, myocardium
- chronic
- Failure, failed
- myocardial, myocardium
- congestive
- Failure, failed
- ventricular
- Insufficiency, insufficient
- myocardial, myocardium (with arteriosclerosis)
- Paralysis, paralytic(complete) (incomplete)
- cardiac
- Syndrome
- low
- output (cardiac)
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Heart Failure
a heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction.Heart Failure, Diastolic
heart failure caused by abnormal myocardial relaxation during diastole leading to defective cardiac filling.Heart Failure, Systolic
heart failure caused by abnormal myocardial contraction during systole leading to defective cardiac emptying.Diastole
post-systolic relaxation of the heart, especially the heart ventricles.Systole
period of contraction of the heart, especially of the heart ventricles.Diastolic Dysfunction
impairment in the filling of the ventricles during diastole. causes include hypertrophic and restrictive cardiomyopathies, coronary artery disease, chronic high blood pressure, aortic stenosis, and aging.Left Ventricular Diastolic Dysfunction, CTCAE|Left ventricular diastolic dysfunction
an adverse event characterized by impaired functioning of the left ventricle of the heart during the diastole phase of the cardiac cycle.Cardiorenal Syndrome
a disorder of the heart and kidneys in which dysfunction of one of the organs induces dysfunction of the other organ.
Patient EducationClinical
Heart Failure
Heart failure means that your heart can't pump enough oxygen-rich blood to meet your body's needs. Heart failure doesn't mean that your heart has stopped or is about to stop beating. But without enough blood flow, your organs may not work well, which can cause serious problems.
The full article covers:
- What is heart failure?
- What causes heart failure?
- Who is more likely to develop heart failure?
- What are the symptoms of heart failure?
- What other problems does heart failure cause?
- How is heart failure diagnosed?
- What are the treatments for heart failure?
- Can heart failure be prevented?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert I50.9 to ICD-9-CMHistory
Code HistoryHistory
Questions About I50.9Overview
Is I50.9 (Heart failure) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report heart failure, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does I50.9 group to?
When heart failure, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 291, 292, 293, with relative weights from 0.5660 to 1.2838 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of I50.9?
Under the General Equivalence Mappings, heart failure, unspecified converts to ICD-9-CM 428.0 (CHF NOS) and 428.9 (heart failure NOS). The mapping is approximate, so confirm the match fits the documentation.
Footnotes
[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:
- The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
- The condition places limitations on self-care, independent living, and social interactions.
