Cardiology Coding Alert

Learn why your cardiologist must specify primary or secondary

Satisfying yourself with an unspecified hypertension code, merely because your cardiologist did not accurately document the patient's condition, could lead your claim into limbo land.
 
Combat these three myths to ensure you find your way to the correct hypertension code every time.

Myth 1: Just Writing 'Hypertension' Is OK

If your cardiologist is in the habit of merely writing "hypertension" on the patient's record, then you should point this problem out to him or her.

"The real key to correct coding for hypertension lies with physician documentation, and we need to educate our [cardiologists] to tell us explicitly" what type of hypertension they're treating, says Charla Prillaman, CPC, CHCO, director of physician compliance for Carolinas Healthcare System in Charlotte, N.C. Cardiologists need to state the details of a patient's hypertension in the medical record, she adds.

Coding for hypertension "really comes down to documentation," agrees Jaime Darling, CPC, a coder with Graybill Medical Group in Escondido, Calif. Often cardiologists will simply write "hypertension" in the diagnosis portion of their notes, which leads a coder to nothing but 401.9 (Essential hypertension; unspecified), she says. Explain to your cardiologists that adequate information for medical purposes isn't always adequate for coding purposes.
 
Action: Ask your cardiologist to indicate whether a patient's hypertension is malignant or benign, and also to define how any other manifestations are related to the hypertension, Darling recommends. For example, the cardiologist should not just document hypertension and renal disease, but should indicate if the patient's hypertension is causing renal disease or if the renal disease is causing hypertension.

Myth 2: No Info? Assume It's Benign

When you don't know whether the hypertension is malignant or benign, you shouldn't automatically assume your cardiologist means benign.

The hypertension table in the ICD-9-CM manual's Index lists three possible categories into which hypertension may fall: Malignant, benign and unspecified. The fourth digit of the hypertension code you report will differ depending on which category you choose. For instance, you'll report 401.0 for malignant essential hypertension, 401.1 for benign essential hypertension and 401.9 for unspecified.

What to look for: "A patient has malignant hypertension when he or she has a recent significant increase over baseline blood pressure that is associated with target organ damage. There is usually vascular damage on funduscopic examination, such as flame-shaped hemorrhages or soft exudates," says Jerome Williams Jr., MD, FACC, a cardiologist with Mid Carolina Cardiology in Charlotte, N.C. To diagnose malignant hypertension, papilledema must be present, Williams says. Up to 1 percent of patients with benign hypertension may develop malignant hypertension--meaning malignant hypertension can be life threatening and may cause a stroke but is much less common than benign hypertension.
 
Common assumption: Because benign hypertension is more common, physicians often assume they are indicating benign hypertension when they simply write "hypertension," Prillaman says. But if the documentation doesn't specifically state "benign" or "malignant," the only accurate choice you have is to report an unspecified code, she adds.

Myth 3: Hypertension Dx Stops at Benign/Malignant

Identifying whether the hypertension is benign or malignant won't tell your payers the whole story. You've got to also show whether the hypertension is primary or secondary to a patient's condition.

Key: When documenting, your cardiologist must learn to link the patient's hypertension to any other manifestations, Darling says. And coders have to learn to discern the manifestations properly to assign the correct code.  

Prime Your Primary Hypertension Skills
 
If the patient's hypertension is primary (also known as "essential hypertension," Williams notes), meaning that another condition is not causing the hypertension, then you need to list the hypertension code first. Then list any manifestations as secondary diagnoses, Darling says.

Keep in mind: Sometimes patients have hypertension with another condition, such as renal disease or renal artery stenosis, and there is one code that includes both conditions, she adds. For instance, the 403 code series indicates hypertensive renal disease, and the 404 series indicates hypertensive heart and renal disease.

Example #1: If your cardiologist documents a patient with benign hypertensive renal disease with renal failure, you would report 403.11 (Hypertensive kidney disease; benign; with chronic kidney disease). You need only this one code to describe the patient's entire condition.

Example #2: If your cardiologist treats a patient with benign hypertensive heart disease with heart failure, you would report 402.11 (Hypertensive heart disease; benign; with heart failure). This code indicates the patient's entire hypertensive status. Note: You would also need to report an additional code to specify the type of heart failure, such as 428.0 (Congestive heart failure, unspecified).

Red flag: If your cardiologist documents the patient has heart disease due to hypertension, he should also indicate whether the disease is with or without heart failure, Darling says. "This [distinction] will help the coder select the best code in the 402 or 404 categories," she adds. And if the patient does have heart failure, remember to assign a separate code to indicate the type of heart failure.

Don't Overlook Secondary Hypertension

A patient has secondary hypertension if the hypertension is "due to" or caused by another condition. ICD-9-CM defines secondary hypertension as "high arterial blood pressure due to or with a variety of primary diseases, such as renal disorders, CNS disorders, endocrine and vascular diseases."

For secondary hypertension, you should report the causal condition as the primary diagnosis and the hypertension as secondary. For example, if a patient has primary aldosteronism that is causing benign hypertension, you might report 255.10 (Primary aldosteronism) as the primary diagnosis and 405.19 (Secondary hypertension; benign; other) as the secondary.