Copyright © 2001 Paolo Barbier

Copyright © 2001 Paolo Barbier

Upper panel: in blue, normal systolic laminar flow through the right ventricular (RV) outflow tract, valve and pulmonary artery (PA). To the right (and at center of sector scan) short axis of the aortic root. 

Lower panel: in yellow/red, mild diastolic pulmonary valve regurgitation. The continuous wave Doppler cursor is positioned through, and parallel to, the regurgitant jet, to obtain the diastolic regurgitant flow velocity pattern (see below). 

Pulmonary artery diatolic pressure (which approximates pulmonary capillary wedge pressure) = mid-diastolic regurgitant pressure gradient (see below) + RV diastolic pressure (approximated by right atrial pressure, which is estimated from inferior vena cava inspiratory collapse).

Estimated normal wedge pressure.
Continuous wave Doppler tracing, transthoracic examination.
Normal subject with minimal pulmonary valve regurgitation. 
Diastolic gradient= 3.9 mmHg

Assuming normal (= 6 mmHg) right atrial pressure, wedge pressure= 3.9+6= 9.9 mmHg. 

Estimated increased wedge pressure.
Continuous wave Doppler tracing, transthoracic examination.
Patient with minimal pulmonary valve regurgitation. 
Diastolic gradient= 15.2 mmHg

Assuming normal (= 6 mmHg) right atrial pressure, wedge pressure= 15.2+6= 21 mmHg.