Pulmonary hypertension (PH) is a condition with five distinct types, including pulmonary arterial hypertension (PAH) — a form caused by stiff, narrowed blood vessels in the lungs. Within each type of PH, there are four functional classes. These classes or grades describe how severe the symptoms of each condition are.

Knowing your PH class helps doctors track the progression of your disease and assess how the condition is affecting your daily life and how well treatments are working. It also lets you know what to expect with PH. Here’s what the different classes mean.

Classes of Pulmonary Hypertension

The World Health Organization uses four PH classes based on how severe your symptoms are. Class 1 is the mildest form, and class 4 is the most serious. These classes are based on how much harder your symptoms make it to do everyday activities.

Your symptoms will vary depending on your medical history and the type of PH you have. Usually, the first thing people notice is shortness of breath. It may start as a symptom that only affects you when exercising, but it can eventually happen even when you’re resting.

As PH progresses, it can cause problems with the right side of your heart and lead to new symptoms like:

• Blue color in your lips or skin
• Swelling in your legs or belly
• Chest tightness or pain in the upper right part of your belly
• Dizziness
• Loss of appetite
• Fast or racing heartbeat
• Extreme tiredness

It’s important to pay attention to your body and keep a written log of your symptoms. This can help your healthcare team understand what’s going on. PH is a serious cardiovascular condition, so regular checkups are essential to monitor heart and lung health.

Class 1 Pulmonary Hypertension

People with class 1 pulmonary hypertension usually don’t have symptoms when resting or when exercising. Because of this, they might not know anything is wrong.

Early screening for PH may include blood tests, chest X-rays, echocardiography (heart ultrasounds), and exercise tolerance tests (like a six-minute walk test). If your doctor sees any abnormalities, they may start to suspect a problem like PH. Before confirming your diagnosis, they’ll need to do a special test known as right-heart catheterization. This test checks the blood pressure on the right side of the heart and lungs. It’s the most accurate way to know whether someone has PH, even before symptoms start.

Treatment of pulmonary hypertension will focus on lifestyle changes and managing the health conditions that led to your PH. Depending on the cause of your PH, your doctor might also prescribe medications such as calcium channel blockers and vasodilators to help relax and open blood vessels in the lungs, making it easier for your heart to pump blood. As PH progresses, your doctor will monitor how well your body is responding to your medications and will make changes as needed.

Class 2 Pulmonary Hypertension

Class 2 PH means you feel fine when resting, but normal daily activities — like cleaning, walking up stairs, or grocery shopping — start to make you feel uncomfortable or short of breath.

This symptom is caused by hypoxia, or low oxygen levels. Your doctor might recommend oxygen therapy to help you breathe better when needed.

Class 3 Pulmonary Hypertension

In class 3 pulmonary hypertension, you may have no symptoms or mild symptoms when resting. But when you move around, you quickly feel very tired and out of breath. You may need to take breaks often when doing basic chores and activities. At this point, it may be helpful to ask for assistance from friends, family, neighbors, or a caregiver for the tasks that are harder to manage on your own.

Class 4 Pulmonary Hypertension

Class 4 is the most severe class of PH. In class 4, you feel symptoms not only when you move but also when you’re resting. Symptoms can be intense, sometimes causing fainting.

Edema (swelling) in the feet and ankles is also common for people with class 4 PH. If you gain more than two pounds in one day or five pounds in a week, call your doctor. You might need water pills, called diuretics, to help get rid of the extra fluid.

In severe cases, PH can lead to right heart failure, which may require more intensive treatments or interventions. If other treatments don’t help, your doctor might talk to you about more advanced care, such as a lung transplant.

Taking Control of Your PH Journey

Your healthcare team, which may include pulmonology and cardiology specialists, can help you figure out which functional class of PH you have. This is important, even if you don’t feel any symptoms yet. Knowing your class gives your doctors a baseline or starting point to work from.

It can also help to talk to your loved ones about your condition. When people close to you understand what PH is and how it affects you, they can offer better support.

If you’re living with PH, it’s a good idea to see a doctor early. As time goes on, it’s essential to follow up with your healthcare provider regularly, especially if you notice new symptoms. Staying on top of your care helps you stay active and independent.

Coping With More Severe Classes of PH

There’s no cure for most types of PH, and it can get worse over time. The goal of PH treatment is to help manage your symptoms so you can feel your best at every stage.

As PH progresses, start thinking about ways to slow down and simplify your routine. Try to focus on what’s most important each day. Think about what tasks you can skip, delay, or get help with.

Your doctor may also change your treatment plan as your PH moves to a higher class. This could mean taking more medications or different ones to help you feel better.

Find Your Team

On myPHteam, the social network for people with pulmonary hypertension and their loved ones, members come together to ask questions, give advice, and share their stories with those who understand life with PH.

What classification of pulmonary hypertension do you have? How does it affect your day-to-day life? Share your experience in the comments below, or start a conversation with others on your Activities page.