Understanding the results of cardiac (heart) testing can feel like learning a foreign language. That said, interpreting these results can help empower people living with pulmonary hypertension (PH) to advocate for themselves and better understand their doctor’s recommendations.

Read on to learn more about right ventricular systolic pressure (RVsP) — one of the important cardiac testing measurements used to diagnose and manage PH.

What Is RVsP?

RVsP refers to the pressure in the right ventricle during systole. A higher RVsP — above 40 millimeters of mercury (mm Hg) — is associated with a higher risk of PH and worse clinical outcomes due to any cause, including PH.

Systole is the phase of a heartbeat where the heart pumps blood from the ventricles to the aorta and pulmonary artery. The right and left ventricles are the two muscular heart chambers (hollow spaces in the heart that collect and move blood).

The right ventricle pumps blood into the pulmonary artery, and the left ventricle pumps blood into the aorta. The other two chambers are the right and left atria, which receive blood from the body and lungs, respectively, and pass the blood to the ventricles.

The pulmonary artery is the blood vessel that sends blood low in oxygen to the lungs. The aorta pumps blood that contains enough oxygen to supply the rest of the body. RVsP can provide an estimate of pressure inside the pulmonary artery.

Because increased pulmonary artery pressure (PAP) is a key feature of PH, using RVsP to estimate PAP is particularly helpful in diagnosing and managing PH. Furthermore, recent research shows a connection between right ventricular function and clinical outcomes for people with PH.

How Is RVsP Measured?

RVsP is measured directly by right heart catheterization (RHC) and estimated with an echocardiogram (often called an “echo”).

Right Heart Catheterization

During right heart catheterization (RHC), a cardiologist (heart doctor) passes small tubes into the heart chambers to take pressure measurements. These measurements include mean (average) pulmonary artery pressure (mPAP) and RVsP. RHC is considered the gold standard for diagnosing PH because it allows doctors to directly measure mPAP and other pressures. An mPAP of greater than 20 mm Hg measured with RHC can indicate the presence of PH.

Although RHC is required to diagnose PH, the procedure is invasive and expensive, and it can be inconvenient for people. As a result, RHC is not used to screen (initially test) for RHC.

Echocardiogram

Unlike RHC, echos are noninvasive — they don’t involve making incisions or entering the body with instruments. An echo is performed on the outside of the body or with minimal contact. Echos also show both direct and indirect signs that can suggest PH. These characteristics make echocardiography a good first-choice screening test for PH. With echo results, doctors can evaluate who will benefit from treatment and who needs their diagnosis confirmed with RHC.

An echo is a heart ultrasound — a type of imaging that uses sound waves to capture moving images of the heart. The most common type is transthoracic echocardiography. During this test, the technician places the ultrasound probe on the chest to produce an image.

Estimating Mean Pulmonary Artery Pressure

To estimate the mean pulmonary artery pressure (mPAP) with an echo, a cardiologist will measure the peak tricuspid regurgitation (TR) velocity and calculate the RVsP. Peak TR velocity measures the highest speed of blood as it passes through the tricuspid valve. The tricuspid valve separates the right atrium and the right ventricle. TR occurs when blood moves in the wrong direction across the tricuspid valve — from the right ventricle to the right atrium.

PH causes TR due to pressure build-up within the pulmonary artery that pushes back against the valve. Echos can measure TR with a Doppler echocardiogram. This technique shows the direction in which blood moves through heart valves and chambers. Peak TR velocity provides an estimate of the peak pressure gradient (PG) (pressure difference) between the right atrium and ventricle, which a doctor uses to calculate the RVsP.

Estimating Right Atrial Pressure

Another estimate needed to calculate the RVsP using an echo is the right atrial pressure (RAP). Because RAP can’t be directly measured with an echo, cardiologists use the diameter (how wide it is) of the inferior vena cava (IVC) and how it changes during respiration (breathing) to estimate it. The IVC is the largest vein in the body that delivers blood low in oxygen to the heart. A cardiologist will use the estimated RAP and PG to calculate the RVsP.

RVsP May Equal the Pulmonary Artery Systolic Pressure

If the pulmonary artery isn’t narrow, RVsP equals the pulmonary artery systolic pressure (PASP). Pulmonary artery narrowing can result from congenital conditions (since birth), infections, liver disease, and heart disease, among other causes. Without pulmonary artery narrowing, RVsP and PASP are used interchangeably, and RVsP can be used directly to assess for PH. Additionally, RVsP can be converted to an estimated mPAP for this purpose.

How Does RVsP Affect PH Management?

Your RVsP results can have a major effect on the diagnosis and treatment of PH. Current PH guidelines recommend further evaluation for people with RVsP greater than 40 mm Hg or TR velocity greater than 2.8 meters per second in someone with dyspnea (difficulty breathing) of unknown cause or right ventricular dysfunction (issues with the right side of the heart).

These recommendations are based on evidence that RVsP greater than 40 mm Hg is associated with an increased risk of complications from PH. Importantly, this number isn’t exact. Some people with an RVsP lower than 40 mm Hg may benefit from further evaluation and treatment based on their situation. Possible complications of PH include liver disease, heart failure, abnormal heart rhythm, and blood vessel rupture.

For those who require further evaluation, RHC is needed to confirm a PH diagnosis and determine treatment recommendations. Once someone is diagnosed with PH, an echo and estimated RVsP can be used to monitor treatment.

One member of myPHteam posted about their experience with PH and RVsP. “I was diagnosed with pulmonary arterial hypertension with a pulmonary artery pressure of 47. The next year, I had an echo and RVsP was at 33. Later, my RVsP was at 10, and I am still taking tadalafil for PAH,” they said. Then they asked fellow members, “What does it mean for me when my RVsP is in normal range?”

Tadalafil (Adcirca) is a medication commonly used to treat pulmonary arterial hypertension (PAH) — a rare form of PH that results from the narrowing of the small lung arteries. This member’s experience with PAH treatment highlights the importance of regularly monitoring PH for treatment response and RVsP’s crucial role in this process.

If your estimated RVsP or mPAP gets worse or doesn’t improve with the recommended treatment, it may indicate the need for a treatment change. This observation could also mean that your PH has worsened. In this case, working together with a doctor to develop a new treatment strategy is recommended.

Talk With Your Doctor

If you or a loved one is living with PH, regular follow-up with a doctor who specializes in the condition is essential. Depending on the underlying cause, a cardiologist, pulmonologist (lung doctor), or both may be appropriate.

PH due to any cause can have severe consequences on a person’s quality of life and life expectancy (the time a person is expected to live). Therefore, early diagnosis and treatment are key. If you or a loved one is concerned you may have PH, you should discuss these concerns with your doctor.

Armed with knowledge about RVsP and pulmonary hypertension, you can work more effectively with your doctor to create a management plan that works for you.

Find Your Team

On myPHteam, the social network for people with pulmonary hypertension and their loved ones, more than 51,000 members come together to ask questions, give advice, and share their stories with others who understand life with pulmonary hypertension.

Are you living with pulmonary hypertension? Have you had your RVsP measured? Share your experience in the comments below, or start a conversation by posting on your Activities page.