ICD-10 Code for CAD: Complete Coding Guide

Coronary Artery Disease (CAD) is one of the most common and serious forms of heart disease. In the medical billing and coding world, accurately documenting and coding CAD is critical for correct reimbursement, tracking patient outcomes, and ensuring compliance with healthcare regulations. The ICD-10 code for CAD serves as a fundamental identifier for healthcare providers and payers.

This comprehensive blog will walk you through the correct ICD-10 coding for CAD, the most common variations, coding tips, and compliance essentials.

What Is CAD (Coronary Artery Disease)?

CAD, or Coronary Artery Disease, refers to the narrowing or blockage of coronary arteries due to plaque buildup. This condition can lead to chest pain (angina), heart attacks, and other complications such as heart failure or arrhythmias.

CAD is also known as Ischemic Heart Disease. Coding CAD correctly in ICD-10 depends on the type, presence of angina, past history, and other associated conditions.

Primary ICD-10 Code for CAD

The primary ICD-10 code for CAD without angina is:

I25.10 – Atherosclerotic heart disease of native coronary artery without angina pectoris

This is the most commonly used code when documenting CAD without any mention of chest pain (angina). It represents chronic ischemic heart disease without current symptoms.

Code Structure Breakdown:

• I25: Chronic ischemic heart diseases
• .1: Atherosclerotic heart disease
• 0: Without angina pectoris

Common ICD-10 Codes Related to CAD

When CAD is documented with specific details such as angina or prior interventions like bypass grafts, different codes are used:

Note:

The use of these codes depends on provider documentation of:

• Type of coronary artery affected (native, bypassed, etc.)
• Presence or absence of angina
• Specific type of angina (e.g., stable, unstable)

 CAD Coding Scenarios and Examples

Let’s look at a few real-world scenarios and the corresponding ICD-10 codes:

Scenario 1:

Patient has documented CAD with no symptoms of angina.
ICD-10 Code: I25.10

 Scenario 2:

Patient has CAD with stable angina.
ICD-10 Code: I25.119

 Scenario 3:

CAD in a patient with a previous coronary artery bypass graft (CABG) and angina.
ICD-10 Code: I25.811

Key Coding Guidelines for CAD

Correct coding requires understanding and applying these guidelines:

1. Always Document the Type of Vessel

• Is it the native coronary artery, autologous vein bypass graft, or synthetic graft?

2. Indicate the Presence or Absence of Angina

• Coders must select a more specific code if angina is present.

3. Multiple Diagnoses May Be Required

• If CAD coexists with conditions like heart failure, hypertension, or diabetes, these must also be coded.

4. Use Combination Codes

• For example, I25.110 is a combination code that includes both CAD and unstable angina.

Documentation Tips for Providers

To ensure accurate ICD-10 coding for CAD, documentation should include:

• Type of CAD (chronic, acute, with angina, etc.)
• Specific coronary artery affected (native or graft)
• Presence of any cardiac procedures (e.g., stents, CABG)
• Type of angina if applicable
• Risk factors like smoking, hyperlipidemia, or family history

CAD and Risk Adjustment

CAD is a hierarchical condition category (HCC) condition, meaning it can impact risk scores in Medicare Advantage and other risk-adjusted payment models. Accurate ICD-10 documentation helps:

• Reflect the patient’s true severity of illness
• Justify additional care or interventions
• Ensure fair reimbursement for chronic conditions

 Common Coding Errors to Avoid

Avoid these frequent mistakes when coding CAD:

•  Using unspecified codes when more specific ones are documented
•  Missing the documentation of angina type
• Not coding for bypass graft involvement
• Confusing old myocardial infarction (I25.2) with current CAD diagnosis

 Summary

Correctly assigning the ICD-10 code for CAD is essential for compliance, reimbursement, and quality reporting. Here’s a quick summary:

• Use I25.10 for CAD without angina in the native coronary artery.
• Use I25.11X series for CAD with various forms of angina.
• Use I25.81X series for patients with bypass grafts.
• Ensure documentation clearly reflects angina status, artery type, and any procedural history.

Final Thoughts

Coronary Artery Disease is a complex and chronic condition, and proper ICD-10 coding supports both clinical accuracy and financial integrity. With the evolving landscape of value-based care and risk adjustment, providers and medical coders must be aligned on precise documentation and specific code selection.

Staying updated with ICD-10-CM guidelines and payer-specific policies ensures smoother claim processing and fewer denials.

Need help with CAD coding or medical billing accuracy?
Our experienced team of medical coders ensures compliance, accuracy, and timely claim submissions for all cardiology-related diagnoses.

Contact us today to streamline your cardiology coding and revenue cycle management.