Coding Elevated Troponin in ICD-10-CM

As coders, we see physicians document “elevated troponin” often. In this coding tip, updated for changes made effective October 1, 2023, we will look at what this could possibly mean, as well as how it is coded in ICD-10-CM.

What is Troponin?:

There are three types of troponins that are detectable after heart muscle damage:

• Troponin I (cTnl) – Unique to heart muscle
• Troponin T (cTnT) – Exists in other muscles, but also in the heart
• Troponin C (cTnC) – A binding subunit of troponin

Troponin is protein found in certain types of muscles. When certain muscles are damaged more troponin escapes into your blood. There is always a small amount of troponin circulating in the bloodstream (undetectable), but this increases when there is damage to the muscle. The higher the level of troponin I and T help determine the severity of heart damage.

An elevated troponin does not always mean that a heart attack has occurred. The physician will use the levels as well as clinical symptoms and history of the patient. When due to heart damage/attack, the troponin levels increase withing 12 hours and will peak around the 24-hour mark. These will likely remain high for several days before normalizing.

Does Elevated Troponin Always Mean Heart Damage/Attack?

Elevated troponin does not always mean that there has been a heart attack. Here are a few of the other causes for an elevated troponin to be found in the bloodstream and show up in testing:

• Patient may have fallen and laid in the floor for several hours
• Extreme grief or stress
• Exercising too often (that’s why they will tell you do not work the same muscle group everyday)
• Chronic kidney disease/End stage renal disease (CKD/ESRD)
• Recent heart surgery
• Pulmonary embolism (PE)
• Disease of the valves of the heart
• Congestive heart failure (acute or chronic)
• Extreme illness such as sepsis
• Irregular heart arrhythmia (especially when cardioversion is needed)
• Angina/coronary spasm
• Cardiomyopathy
• Inflammation such as myocarditis and pericarditis
• Elevated blood pressure
• Drug use such as cocaine or methamphetamines
• Certain medications
• Trauma

Why Would a Troponin Test be Needed?

There are many reasons that the physician may order the troponin level to be tested. Here are the most common reasons:

• Chest pain (typically the first test to be ordered after an EKG)
• Excessive sweating
• Difficulty breathing or shortness of breath
• Dizziness/feeling faint
• Anxiety
• Heart palpitations or new arrhythmia
• Pain that spread in the arm and up the shoulder to the neck or jaw
• Patient found down/unconscious

How is Elevated Troponin Coded?

The first thing a coder must do is review the patient’s health record for the diagnosis that the physician determined after study of the labs, tests, and other clinical findings to be responsible for this. If the patient ruled in for a heart attack, that is what would be coded. Any diagnosis that is identified to cause the elevation in the troponin level is what is coded. In the absence of a cause identified, the physician will sometimes list the diagnosis of “elevated troponin.” This is where it gets tricky for coders.

In the past, the index had led the coder to code R77.8, Other specified abnormalities of plasma proteins. As of October 1, 2023, the index entry of “troponin” was corrected under the main term of “elevated” within the ICD-10-CM Index. Below is what the index states to code as of October 1, 2023: 

Elevated, elevation
troponin R79.89

There is an AHA Coding Clinic from Second Quarter 2019, that states to use code R79.89 as well. The index has now been updated to reflect this advice.

Authored by Kim Boy, RHIT, CDIP, CCS, CCS-P

References
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1860726/
https://my.clevelandclinic.org/health/diagnostics/22770-troponin-test
https://www.healthgrades.com/right-care/heart-health/troponin-levels?tpc=latest-news

ICD-10-CM Official Guidelines for Coding and Reporting FY 2024
AHA Coding Clinic for ICD-10-CM/PCS, Second Quarter 2019: Page 6
ICD-10-CM Alphabetic Index