2025 ICD-10-CM Diagnosis Code I45.81

Approximate Synonyms

The following list of clinical terms are approximate synonyms, alternative descriptions, or common phrases that might be used by patients, healthcare providers, or medical coders to describe the same condition. These synonyms and related diagnosis terms are often used when searching for an ICD-10 code, especially when the exact medical terminology is unclear. Whether you're looking for lay terms, similar diagnosis names, or common language alternatives, this list can help guide you to the correct ICD-10 classification.

Clinical Classification

Clinical Classifications group individual ICD-10-CM diagnosis codes into broader, clinically meaningful categories. These categories help simplify complex data by organizing related conditions under common clinical themes.

They are especially useful for data analysis, reporting, and clinical decision-making. Even when diagnosis codes differ, similar conditions can be grouped together based on their clinical relevance. Each category is assigned a unique CCSR code that represents a specific clinical concept, often tied to a body system or medical specialty.

Clinical Information

• Andersen Syndrome

  a form of inherited long qt syndrome (or lqt7) that is characterized by a triad of potassium-sensitive periodic paralysis, ventricular ectopic beats, and abnormal features such as short stature, low-set ears, and scoliosis. it results from mutations of kcnj2 gene which encodes a channel protein (inward rectifier potassium channels) that regulates resting membrane potential.

• Long QT Syndrome

  a condition that is characterized by episodes of fainting (syncope) and varying degree of ventricular arrhythmia as indicated by the prolonged qt interval. the inherited forms are caused by mutation of genes encoding cardiac ion channel proteins. the two major forms are romano-ward syndrome and jervell-lange nielsen syndrome.

• Romano-Ward Syndrome

  a form of long qt syndrome that is without congenital deafness. it is caused by mutation of the kcnq1 gene which encodes a protein in the voltage-gated potassium channel.

MS-DRG Mapping for ICD-10-CM Code I45.81

Diagnosis-Related Groups (DRGs) are used to classify hospital cases for billing and healthcare management. They help standardize how hospitals and other providers are reimbursed for inpatient care. Patients are grouped based on their principal diagnosis into broader categories called Major Diagnostic Categories (MDCs).

Once assigned to a DRG, the hospital receives a set payment for the patient’s care, regardless of the actual services provided. This fixed rate is intended to cover the typical cost of treating patients within that group. The payment amount depends on the DRG's relative weight, which reflects the expected complexity and cost of care based on the severity of the patient’s condition.

Diagnostic related groups encourage healthcare providers to focus on quality and efficiency in patient care while managing costs effectively. The diagnosis code is present in the following groups for version MS-DRG V42.0 applicable from 10/01/2024 through 09/30/2025.

Convert I45.81 to ICD-9-CM

Below are the ICD-9 codes that most closely match this ICD-10 code, based on the General Equivalence Mappings (GEMs). This ICD-10 to ICD-9 crosswalk tool is helpful for coders who need to reference legacy diagnosis codes for audits, historical claims, or approximate code comparisons.

Patient Education

Arrhythmia

An arrhythmia is a problem with the rate or rhythm of your heartbeat. It means that your heart beats too quickly, too slowly, or with an irregular pattern. When the heart beats faster than normal, it is called tachycardia. When the heart beats too slowly, it is called bradycardia. The most common type of arrhythmia is atrial fibrillation, which causes an irregular and fast heart beat.

Many factors can affect your heart's rhythm, such as having had a heart attack, smoking, congenital heart defects, and stress. Some substances or medicines may also cause arrhythmias.

Symptoms of arrhythmias include:

• Fast or slow heart beat
• Skipping beats
• Lightheadedness or dizziness
• Chest pain
• Shortness of breath
• Sweating

Your doctor can run tests to find out if you have an arrhythmia. Treatment to restore a normal heart rhythm may include medicines, an implantable cardioverter-defibrillator (ICD) or pacemaker, or sometimes surgery.

NIH: National Heart, Lung, and Blood Institute

[Learn More in MedlinePlus]

Jervell and Lange-Nielsen syndrome

Jervell and Lange-Nielsen syndrome is a condition that causes profound hearing loss from birth and a disruption of the heart's normal rhythm (arrhythmia). This disorder is a form of long QT syndrome, which is a heart condition that causes the heart (cardiac) muscle to take longer than usual to recharge between beats. Beginning in early childhood, the irregular heartbeats increase the risk of fainting (syncope) and sudden death.

[Learn More in MedlinePlus]

Romano-Ward syndrome

Romano-Ward syndrome is a condition that causes a disruption of the heart's normal rhythm (arrhythmia). This disorder is a form of long QT syndrome, which is a heart condition that causes the heart (cardiac) muscle to take longer than usual to recharge between beats. The term "long QT" refers to a specific pattern of heart activity that is detected with an electrocardiogram (ECG or EKG), which is a test used to measure the electrical activity of the heart. In people with long QT syndrome, the part of the heartbeat known as the QT interval is abnormally long. Abnormalities in the time it takes to recharge the heart lead to abnormal heart rhythms.

The arrhythmia associated with Romano-Ward syndrome can lead to fainting (syncope) or cardiac arrest and sudden death. However, some people with Romano-Ward syndrome never experience any health problems associated with the condition.

Fifteen types of long QT syndrome have been defined based on their genetic cause. Some types of long QT syndrome involve other cardiac abnormalities or problems with additional body systems. Romano-Ward syndrome encompasses those types that involve only a long QT interval without other abnormalities.

[Learn More in MedlinePlus]

Code History

• FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
• FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
• FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
• FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
• FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
• FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
• FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
• FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
• FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.