PULMONARY REGURGITATION (my class notes)

     By far the most common cause of pathologic pulmonary regurgitation is dilation of the valve ring secondary to pulmonary hypertension. The second most common cause is infective endocarditis. Iatrogenic significant pulmonary regurgitation may be present in patients following treatment for pulmonary valve stenosis or tetralogy of Fallot.

     Isolated pulmonary regurgitation may lead to right ventricular volume overload. Right ventricular volume overload (RVVO) is diagnosed by the echocardiographic findings of right ventricular dilatation and paradoxical interventricular septal motion. RVVO may be diagnosed with two-dimensional echo as right ventricular dilatation and flattening of the interventricular septum during diastole with restoration of the normal circular configuration during ventricular systole best seen in the parasternal short-axis of the left ventricle at the level of the papillary muscles.

     Color Doppler findings indicate significant pulmonary regurgitation:

Ø Wide jet width at origin

Ø Jet width/Right ventricular outflow tract width more than 70 %

Ø Holodiastolic flow reversal in the main pulmonary artery

Ø Jet length more than 10 mm

     Pulmonary artery end-diastolic pressure can be calculated by the formula:

     PAEDP (mmHg) = 4xend-diastolic velocity PR2 + RAP (mmHg)

     Normal PAEDP is 4 to 12 mmHg

     The estimation of the PAEDP reflects the pulmonary artery wedge pressure.

     Mean Pulmonary Artery Pressure may be calculated by the formula:

     MPAP (mmHg) = 4x peak velocity PR2

     The normal range for the MPAP is 9 to 18 mmHg.