Pulmonary arterial pressure can be estimated by transesophageal pulsed Doppler echocardiography

We examined whether pulmonary arterial pressure can be estimated on the bas is of pulmonary arterial flow velocity determined via intraoperative pulsed Doppler transesophageal echocardiography (TEE) in 20 patients undergoing c ardiac surgery. Standard pulmonary artery measurements were taken as well. Measurements were taken before sternotomy, after pericardiotomy, after card iopulmonary bypass, and after sternum closure. The variables obtained by TE E included preejection period (PEP), acceleration time (AT), right ventricu lar ejection time (RVET), and R-R interval (RR). Five ratios were calculate d as indices of pulmonary arterial pressure-PEP/AT, PEP/RVET, AT/RVET, PEP/ root RR, and AT/root RR-and were compared with pulmonary artery catheteriza tion findings, i.e., systolic pulmonary arterial pressure (sPAP), log sPAP, mean PAP (mPAP), and log mPAP. Before sternotomy, PEP/AT, PEP/root RR, and AT/root RR showed significant correlation with all pulmonary artery cathet erization values. AT/RVET showed correlation with all pulmonary artery valu es except log mPAP. PEP/AT showed the closest correlation with sPAP (r = 0. 771) and log sPAP (r = 0.789). PEP/AT also showed close correlation with mP AP (r = 0.764) and log mPAP (r = 0.777). Significant agreement between sPAP and mPAP values calculated from a regression equation and values measured via pulmonary artery catheter was observed by plotting the differences agai nst the mean values of the two measurements. We therefore conclude that non invasive estimation of pulmonary arterial pressure is feasible via intraope rative TEE when sternotomy is not involved.