ICD-10-CM Code I51.9

Heart disease, unspecified

Version 2020 Billable Code

Valid for Submission

I51.9 is a billable code used to specify a medical diagnosis of heart disease, unspecified. The code is valid for the year 2020 for the submission of HIPAA-covered transactions. The ICD-10-CM code I51.9 might also be used to specify conditions or terms like acute heart disease, cachexia, cardiac cachexia, cardiac cirrhosis, cardiac complication, cardiac disease in pregnancy, etc

Short Description:Heart disease, unspecified
Long Description:Heart disease, unspecified

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code I51.9 are found in the index:

  • - Morbus - See Also: Disease;
    • - cordis - See Also: Disease, heart; - I51.9


The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

  • Acute heart disease
  • Cachexia
  • Cardiac cachexia
  • Cardiac cirrhosis
  • Cardiac complication
  • Cardiac disease in pregnancy
  • Cardiac disease treatment started
  • Cardiac portal cirrhosis
  • Cardiac treatment changed
  • Cardiac: dubious diagnostic criteria
  • Chronic heart disease
  • Disorder of left atrium as complication of procedure
  • Disorder of right cardiac ventricle
  • Distribution of body fat loss - finding
  • Heart disease
  • Heart disease co-occurrent with human immunodeficiency virus infection
  • Heart disease due to ionizing radiation
  • Heart disease in mother complicating childbirth
  • Heart disease in mother complicating pregnancy, childbirth AND/OR puerperium
  • Hypogonadism with anosmia
  • Hypogonadotropic hypogonadism due to isolated gonadotropin deficiency
  • Hypoxia-associated cirrhosis
  • Kallman syndrome with heart disease
  • Loss of sense of smell
  • Myocardial lesion

Clinical Information

  • CARCINOID HEART DISEASE-. cardiac manifestation of gastrointestinal carcinoid tumor that metastasizes to the liver. substances secreted by the tumor cells including serotonin promote fibrous plaque formation in endocardium and its underlying layers. these deposits cause distortion of the tricuspid valve and the pulmonary valve eventually leading to stenosis and valve regurgitation.
  • CORONARY DISEASE-. an imbalance between myocardial functional requirements and the capacity of the coronary vessels to supply sufficient blood flow. it is a form of myocardial ischemia insufficient blood supply to the heart muscle caused by a decreased capacity of the coronary vessels.
  • HEART DISEASES-. pathological conditions involving the heart including its structural and functional abnormalities.
  • HEART VALVE DISEASES-. pathological conditions involving any of the various heart valves and the associated structures papillary muscles and chordae tendineae.
  • PULMONARY HEART DISEASE-. hypertrophy and dilation of the right ventricle of the heart that is caused by pulmonary hypertension. this condition is often associated with pulmonary parenchymal or vascular diseases such as chronic obstructive pulmonary disease and pulmonary embolism.
  • RHEUMATIC HEART DISEASE-. cardiac manifestation of systemic rheumatological conditions such as rheumatic fever. rheumatic heart disease can involve any part the heart most often the heart valves and the endocardium.
  • MYOCARDIAL ISCHEMIA-. a disorder of cardiac function caused by insufficient blood flow to the muscle tissue of the heart. the decreased blood flow may be due to narrowing of the coronary arteries coronary artery disease to obstruction by a thrombus coronary thrombosis or less commonly to diffuse narrowing of arterioles and other small vessels within the heart. severe interruption of the blood supply to the myocardial tissue may result in necrosis of cardiac muscle myocardial infarction.

Diagnostic Related Groups

The ICD-10 code I51.9 is grouped in the following groups for version MS-DRG V37.0 What are Diagnostic Related Groups?
The Diagnostic Related Groups (DRGs) are a patient classification scheme which provides a means of relating the type of patients a hospital treats. The DRGs divides all possible principal diagnoses into mutually exclusive principal diagnosis areas referred to as Major Diagnostic Categories (MDC).
applicable from 10/01/2019 through 09/30/2020.


Convert I51.9 to ICD-9

  • 429.9 - Heart disease NOS (Approximate Flag)

Code Classification

  • Diseases of the circulatory system (I00–I99)
    • Other forms of heart disease (I30-I52)
      • Complications and ill-defined descriptions of heart disease (I51)

Code History

  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016
    (First year ICD-10-CM implemented into the HIPAA code set)
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020

Information for Patients

Heart Diseases

If you're like most people, you think that heart disease is a problem for others. But heart disease is the number one killer in the U.S. It is also a major cause of disability. There are many different forms of heart disease. The most common cause of heart disease is narrowing or blockage of the coronary arteries, the blood vessels that supply blood to the heart itself. This is called coronary artery disease and happens slowly over time. It's the major reason people have heart attacks.

Other kinds of heart problems may happen to the valves in the heart, or the heart may not pump well and cause heart failure. Some people are born with heart disease.

You can help reduce your risk of heart disease by taking steps to control factors that put you at greater risk:

  • Control your blood pressure
  • Lower your cholesterol
  • Don't smoke
  • Get enough exercise

NIH: National Heart, Lung, and Blood Institute

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