Variables
Systolic pulmonary artery pressure (sPAP)
sPAP = 4(TRVmax)2 + RAP
Mean pulmonary artery pressure (mPAP)
mPAP = 4(Early PI velocity)2 + RAP
mPAP = 1/3 sPAP + 2/3 dPAP
mPAP = 79 - 0.45 × Acceleration Time
Abnormal: ≥25 mmHg
Diastolic pulmonary artery pressure (dPAP)
dPAP = 4(End PI velocity)2 + RAP

RAP, Right atrial pressure.