The Finer Points of Coding Pulmonary Hypertension

PH may be rare, but it can be deadly – and coding it correctly is imperative.

Being that February is American Heart Month, today I want to report on hypertension, and specifically pulmonary hypertension. High blood pressure, otherwise known as hypertension, is very common – about one in three American adults has it – and you likely know someone with the condition. You might even have it yourself.

Pulmonary arterial hypertension, on the other hand, is much rarer, and can be much deadlier. When someone is diagnosed with regular (systemic) hypertension, it means that the force of blood pushing against the sides of the arteries is too strong, which raises the risk of heart attack and stroke. Pulmonary hypertension is a form of high blood pressure that occurs in the lungs. It can be triggered by a variety of factors, including sleep apnea and chronic obstructive pulmonary disease (COPD). Per the Centers for Disease Control and Prevention (CDC), the true prevalence is still unknown, but it’s estimated that between 50-100 people per million have the condition – so getting the right diagnosis and treatment is crucial for those who have it, because pulmonary hypertension worsens over time, and there is currently no cure. Here are a few facts about pulmonary hypertension, and then we will look at the proper way to code the condition.

1. The exact cause of pulmonary hypertension (PH) is unknown. Pulmonary hypertension is diagnosed when mean, or average, blood pressure leaving the arteries on the right side of the heart is measured at 20 mmHg or higher. Usually found via an ECHO or cardiac catheterization, fatigue and shortness of breath are common symptoms.
   
2. There are five types of PH, which we will look at shortly.
   
3. Pulmonary hypertension affects women more than men. Per the Pulmonary Hypertension Association, PH is most often diagnosed in women between the ages of 30 and 60. They don’t know exactly why it is more prevalent in women, but they think it has something to do with estrogen.
   
4. Pulmonary hypertension is difficult to diagnose, and usually under-coded and under-documented. Because it mimics symptoms of other diagnoses such as COPD and congestive heart failure (CHF), the condition can be misdiagnosed, and once a formal diagnosis is made, the condition is usually at its last stages.
   
5. There is no cure for pulmonary hypertension, but there are effective ways to manage the disease. The typical prognosis is much better today than it was 25 years ago. The median survival from time of diagnosis used to be 2.5 years, but now most patients are living seven to 10 years, and some are living as long as 20 years. The earlier the condition is diagnosed, the better the outcome.

Now, let’s look at coding for pulmonary hypertension. Pulmonary hypertension is classified into five groups, per the World Health Organization (WHO), depending on the cause of the disease, and coding is determined by what the underlying cause is.

Group 1: Pulmonary arterial hypertension (PAH):

This is the most recognized category of pulmonary hypertension, and includes both primary and secondary causes. The two codes to report this type of pulmonary hypertension are I27.0 (primary pulmonary hypertension) and I27.21 (secondary pulmonary arterial hypertension).

Group 2: Pulmonary hypertension due to left heart disease:

This category of pulmonary hypertension is caused by failure of the left ventricle or left-sided valvular heart disease (mitral and/or aortic valve disease). The most common cause of pulmonary hypertension is left heart disease. To report this type, code I27.22 (pulmonary hypertension due to left heart disease) is assigned.

Group 3: Pulmonary hypertension occurring secondary to lung disease and/or hypoxia:

This category of pulmonary hypertension is caused by COPD/emphysema, pulmonary fibrosis, sleep apnea, or other sleep disorders, and long-term exposure to high altitudes. The code to report this type is I27.23 (pulmonary hypertension due to lung disease and hypoxia).

Group 4: Chronic thromboembolic hypertension:

This category is caused by clotting disorders or blood clots in the lungs also called pulmonary emboli. Code I27.24 (chronic thromboembolic pulmonary hypertension) is used to report this type.

Group 5: Other secondary pulmonary hypertension:

This would include causes such as chronic polycythemia vera, essential thrombocytopenia, sarcoidosis, vasculitis, thyroid or glycogen storage disease, kidney disease, anything that presses on the pulmonary artery (like a tumor), or multifactorial. I27.29 (other secondary pulmonary hypertension) is reported for this type.

Next, Let’s review the Official Coding Guideline for PH.

Pulmonary hypertension is classified to category I27, Other pulmonary heart diseases. For secondary pulmonary hypertension (I27.1, I27.2-), code also any associated conditions or adverse effects of drugs or toxins. The sequencing is based on the reason for the encounter, except for adverse effects of drugs (See Section I.C.19.e.).

Some last coding tips on PH include the following:

• Primary pulmonary hypertension, I27.20, is a CC while secondary pulmonary hypertension codes are not; and
• The default code for pulmonary hypertension NOS is code I27.20-; please note, this code is not a complication or comorbidity (CC) or major CC (MCC), but increases the severity of illness (SOI) and risk of mortality (ROM) to a 2/2.