Pulmonary Artery diastolic pressure assessment

Echocardiography Textbook

For the assessment of pulmonary artery diastolic pressure, the maximum rate of Pulmonary Regurgitation is determined and using the Bernoulli's formula, the pressure gradient between the Pulmonary Artery and the Right Ventricle calculated (Modern ultrasound machines automatically calculate the pressure gradient (PG) after tracing the spectrogram by the operator).
Pulmonary regurgitation is examined by spectral Doppler in the Apical Four - chamber position.

Bernoulli's formula:

V - maximum flow rate.

Tricuspid regurgitation is normal in 75-80% of the population. If the regulation signal is not optimal, echo contrast agents can be used.

If there is no pulmonary artery stenosis, it can be assumed that the systolic pressure in the pulmonary artery and the right ventricle is the same. Systolic pressure in the pulmonary artery is calculated using the following formula:

PPA - Pulmonary artery diastolic pressure. PRV - Diastolic pressure in the right ventricle. PGTV - Diastolic pressure gradient on the pulmonary valve (between PA and RV). PRA - Pressure in the right atrium.

Right atrial pressure (PRA) can be measured by examining the collapse of the Inferior Vena Cava during deep inspiration (in the norm, the diameter decreases by more than 50%):

IVC diameter	Reaction on deep inhale	PRA
<15	Collapse	0-5
15-25	>50%	5-10
15-25	<50%	10-15
>25	<50%	15-20
>25 + Hepatic Vein dilatation	No reaction	>20