How is PAH Diagnosed?

Pulmonary arterial hypertension (PAH) is diagnosed by measuring the pressure in the pulmonary arteries.

Diagnostic Methods for PAH

The primary methods used to diagnose PAH involve directly measuring the pressure within the pulmonary arteries. These tests are critical because elevated pulmonary artery pressure is a key indicator of PAH.

Cardiac Catheterization

• Purpose: This is a more invasive procedure and is considered the gold standard for measuring pulmonary artery pressure.
• How it works: A thin, flexible tube (catheter) is inserted into a large vein, usually in the groin or neck, and guided to the right side of the heart and into the pulmonary arteries.
• Measurement: The catheter has a pressure sensor that directly measures the blood pressure in the pulmonary arteries.

Echocardiography

• Purpose: This non-invasive imaging test uses ultrasound to visualize the heart.
• How it works: Sound waves create images of the heart and can indirectly estimate the pressure in the pulmonary arteries.
• Measurement: Although it does not measure pressure directly, an echocardiogram can provide an estimation of pulmonary artery pressure and assess the size and function of the heart chambers.

Normal vs. Elevated Pressure

According to the provided information:

• Normal Pulmonary Artery Pressure: The normal range is between 11 and 20 millimeters of mercury (mm Hg).
• Elevated Pressure: If the measured pressure is consistently higher than 20 mm Hg, this is an indication of pulmonary hypertension, potentially PAH.

Conclusion

Diagnosis of PAH relies on tests that measure pulmonary artery pressure, including cardiac catheterization, which provides a direct reading, and echocardiography, which provides an estimated measurement. If pressures are higher than the normal range (11-20 mm Hg), it can be indicative of PAH.