One hundred two patients were studied with simultaneous right-heart catheterization (RHC) and echocardiography. MPAP was calculated by adding the right ventricular¨Cright atrial mean systolic gradient to right atrial pressure.
The mean difference between MPAP calculated using this method and RHC-derived MPAP was ?.6 mm Hg, less than that of traditional systolic pulmonary arterial pressure (SPAP; ?.4 mm Hg) and MPAP estimated using the pulmonary regurgitation method (?3.9 mm Hg). The median absolute percentage difference of the MPAP calculations relative to RHC was significantly less with this method than with the pulmonary regurgitation method (18 % vs 71 % ; P < .001) and similar to the SPAP method (both 18 % ; P = .30).
MPAP calculated using the proposed method is as accurate as SPAP calculation and less variable than previous methods, thus allowing widespread clinical use.