Right ventricular myocardial velocities and timing estimate pulmonary artery systolic pressure

Abstract 

Background

Non-invasive estimation of pulmonary artery systolic pressure (PASP) is important for identifying and following up patients. We aimed at revisiting the accuracy of various right ventricular (RV) Doppler echocardiographic measurements of PASP.

Methods

Twenty-eight patients were studied with simultaneous right heart catheterization (RHC), conventional and tissue Doppler echocardiography (TDE). We measured RV–right atrial (RA) peak pressure drop, RV spectral filling and myocardial velocities and timings.

Results

RV–RA peak pressure drop (r=0.89, p<0.001) strongly correlated with PASP. Both RV spectral and myocardial measurements of isovolumic relaxation time (IVRT) modestly correlated with PASP (r=0.63, p<0.01 and <0.001). Time interval measurements missed 6 and 9 cases with normal PASP by using proposed cut off values. Combining myocardial IVRT and isovolumic contraction velocity (IVCV) in a formula, predicted PASP in all but 3 of our patients. In addition, TDE measurements were obtainable in all cases compared to RV–RA gradient which were measurable in only 64% of patients.

Conclusion

RV–RA peak pressure drop is the most accurate non-invasive method for assessing PASP. Combining myocardial IVCV and IVRT can be used accurately in estimating PASP being more feasible than RV–RA drop. Such additional measurement might be important in patients follow-up when RV–RA gradient is difficult to obtain.

Keywords: Pulmonary artery systolic pressures, Right atrial pressure, Isovolumic relaxation time, Isovolumic contraction velocity, Tissue Doppler echocardiography