Pulmonary Vascular Resistance Index (Wave Velocity Maximum)

What This Test Measures

Pulmonary vascular resistance (PVR) is a measure of how much resistance your lungs’ blood vessels offer to blood flow. This test specifically looks at the maximum velocity of blood flow waves (wave velocity maximum) to calculate an index related to these vessels. It’s often used alongside other cardiac or pulmonary function tests to identify issues like pulmonary hypertension or other vascular disorders.

Why It’s Done

Your healthcare provider may order this test if you have symptoms like shortness of breath, chest pain, or fatigue that could suggest lung or heart problems. It’s also used in specialized evaluations, such as before surgeries involving the heart or lungs, or to monitor chronic conditions like pulmonary hypertension.

Sample and Procedure

This test typically involves a procedure called echocardiography (ultrasound of the heart) or a specialized Doppler ultrasound. A small probe is placed on your chest, and sound waves are used to measure blood flow velocity in your lungs. No special preparation is needed, but you may be asked to lie still while the test is performed.

What to Expect After the Test

You may feel some pressure or discomfort from the ultrasound probe, but it’s usually brief. You can return to your normal activities immediately unless your provider advises otherwise. Results are usually available within a few days, and your doctor will discuss them with you during your follow-up visit.