Cardiology Coding Alert

Hint: Report a secondary code from category N18- when reporting from category I12-.

Reporting the correct ICD-10-CM codes on your hypertension claim can be tricky because you have so many options. You must also make sure to follow guidance the ICD-10-CM Guidelines for Coding and Reporting sets forth. Chapter 9 in the guidelines covers cardiology, and it’s a particularly robust chapter. For example, you will see many rules for how to correctly report hypertension.

First, Define Hypertension for Clarity

FAQ 1: What is hypertension?

Answer: Hypertension (HTN or HBP) is the force/pressure of the blood against arterial walls that is too high, says Julie-Leah J. Harding, CPC, CPMA, CEMC, CCC, CRC, RMC, PCA, CCP, SCP-ED, CDIS, AHIMA-approved ICD-10 trainer and ambassador and director of clinical compliance-cardiovascular surgery at Boston Children’s Hospital in Boston, Massachusetts.

High blood pressure is commonly defined as a blood pressure of 140/90 and is considered severe if the blood pressure 180/120, says Carol Hodge, CPC, CPMA, CDEO, CCC, CEMC, CPB, CFPC, COBGC, senior documentation specialist at St. Joseph’s/Candler Medical Group.

“Blood pressure is comprised of systolic and diastolic pressures (systolic/diastolic),” Harding explains. “Systolic pressure is the pressure when the ventricles pump blood out of the heart. Diastolic pressure is the pressure between heartbeats when the heart is filling with blood.”

Remember to Report CKD Stage for Hypertensive CKD

FAQ 2: What ICD-10-CM code should I report if my cardiologist documents hypertensive chronic kidney disease (CKD)?

Answer: If your cardiologist diagnoses the patient with both hypertension and a condition that falls under category N18- (Chronic kidney disease (CKD)), report the appropriate code from category I12- (Hypertensive chronic kidney disease), per the guidelines.

You should not code CKD as hypertensive if your cardiologist indicates that the CKD is not related to the hypertension, according to the guidelines.

Secondary code: When you report a code from category I12-, you should also report a secondary code from category N18- to indicate the stage of CKD. ICD-10-CM classifies CKD based upon severity and designates this severity into the following stages:

• For stage 1, report N18.1 (Chronic kidney disease, stage 1).
• For stage 2 mild CKD, report N18.2 (Chronic kidney disease, stage 2 (mild)).
• For stage 3 moderate CKD, report N18.30 (Chronic kidney disease, stage 3 unspecified) through N18.32 (Chronic kidney disease, stage 3b).
• For stage 4 severe CKD, report N18.4 (Chronic kidney disease, stage 4 (severe)).
• For stage 5 CKD, report N18.5 (Chronic kidney disease, stage 5).
• For end stage renal disease (ESRD), report N18.6 (End stage renal disease). However, if your cardiologist documents both a stage of CKD and ESRD, only report N18.6, per the guidelines.

Patient Has Hypertensive Heart and CKD? Do This

FAQ 3: The patient has hypertension with both heart and kidney involvement. How should I report this?

Answer: If the patient has hypertension with both heart and kidney involvement, report a code from category I13- (Hypertensive heart and chronic kidney disease), per the guidelines. If your cardiologist documents that the patient also has heart failure, report the appropriate code from category I50- (Heart failure) to identify the exact type of heart failure.

Don’t miss: When you report a code from category I13-, you must also report the appropriate secondary code from category N18- to identify the CKD stage, per the guidelines.

Coding tip: Category II3- is a combination category for hypertensive heart and CKD. If a patient has all three conditions, hypertension, heart disease, and CKD, report a code from category I13-. Do not report individual codes for hypertension, heart disease, and CKD, or codes from categories I11- (Hypertensive heart disease) or I12- (Hypertensive chronic kidney disease).

If the patient has both acute renal failure and CKD, you must also report the appropriate code for acute renal failure.

Report 2 Codes for This Uncontrolled Hypertension Case

FAQ 4: The patient has hypertensive heart disease with cardiomegaly and acute on chronic diastolic congestive heart failure. These two conditions are related. My cardiologist documented that the patient’s hypertension is uncontrolled because it is not responding to their current therapeutic regimen. Which ICD-10-CM codes should I report on my claim?

Answer: This is an example of uncontrolled hypertension, where the patient’s hypertension is not responding to their current therapeutic regimen. You should report the appropriate code from categories I10-(Essential (primary) hypertension) through I15- (Secondary hypertension), per the guidelines.

On your claim, report I11.0 (Hypertensive heart disease with heart failure) and I50.33 (Acute on chronic diastolic (congestive) heart failure).

Don’t miss: Uncontrolled hypertension can also refer to untreated hypertension.

Grasp Hypertensive Retinopathy Definition

FAQ 5: What is hypertensive retinopathy, and how should I report this condition?

Answer: Hypertensive retinopathy is damage to the retinal blood vessels attributed to hypertension. When reporting hypertensive retinopathy, first choose a code from subcategory H35.0- (Background retinopathy and retinal vascular changes), according to the guidelines.

For the second code, choose the appropriate code from categories I10- (Essential primary hypertension) through I15- (Secondary hypertension) to indicate the patient’s type of hypertension.

The sequencing of these two codes is based upon the reason for the encounter.

Secondary Hypertension Due to Underlying Condition

FAQ 6: How should I report secondary hypertension?

Answer: Secondary high blood pressure (secondary hypertension) is high blood pressure that’s caused by another medical condition, says Rebecca Sanzone, CPC, CPMA, quality assurance specialist at St. Vincent Medical Group/Accension Health and coding consultant at the American College of Cardiology. Secondary hypertension can be caused by conditions that affect the kidneys, arteries, heart, or endocrine system. Secondary hypertension can also occur during pregnancy.

In the case of secondary hypertension, report two codes on your claim: one code to identify the underlying etiology and another code from category I15- to identify the specific type of hypertension.

Sequencing of codes is determined by the reason for the encounter.

Don’t miss: Only about 5 to 10 percent of hypertension cases are thought to result from secondary causes, according to Sanzone.

Editor’s note: Stay tuned for next month’s Cardiology Coding Alert to learn even more about hypertension.