Shojaeifard M, Daryanavard A, Karimi Behnagh A, Moradian M, Erami S, Dehghani Mohammad Abadi H.Cardiovasc Ultrasound. 2020 May 15;18(1):14. doi: 10.1186/s12947-020-00196-0.PMID: 32414369 Free PMC article.
Objectives: Very few reports have described the Doppler-derived echocardiographic parameters for mechanical pulmonary valve prosthesis (MPVP). This study aims to describe the normal Doppler hemodynamic profile of MPVP using Doppler echocardiography.
Methods: The current prospective, single center observational study enrolled 108 patients who underwent pulmonary valve replacement (PVR) surgery for the first time and had a normally functioning prosthesis post-operation. The hemodynamic performance of MPVPs, considering flow dependent and flow independent parameters, was evaluated at two follow-up points, at week one and week four post-operation. All assessments were conducted by an experienced echocardiographer.
Results: The mean age (±SD) of the participants was 26.4 (±8.98). Tetralogy of Fallot (ToF) was the most common underlying disease leading to PVR, with a prevalence of 88%. At first week post-operation, measurement of indices reported the following values (±SD): peak pressure gradient (PPG): 18.51(±7.64) mm Hg; mean pressure gradient (MPG): 10.88(±5.62) mm Hg; peak velocity (PV): 1.97(±0.43)m/s; doppler velocity index (DVI): 0.61(±18); pulmonary velocity acceleration time (PVAT): 87.35(±15.16) ms; effective orifice area (EOA): 2.98(±1.02) cm2;and effective orifice area to body surface area ratio (EOA/ BSA): 1.81(±0.62) cm2/m2. Comparing these measurements with those obtained from the second follow-up (at week four post-op) failed to hold significant difference in all values except for PVAT, which had increased from its primary value (p = 0.038). Also, right ventricular (RV) function showed significant improvement throughout the follow up period.
Conclusion: The findings of this study help strengthen the previously scarce data pool and better establish the normal values for Doppler hemodynamics in mechanical pulmonary prosthesis.
Fig. 1 Normal functioning of mechanical prosthesis in pulmonary position. a Normal opening of the prosthesis. b Normal closing of the prosthesis
Fig. 2 Doppler evaluation of a prosthetic pulmonary valve. a Tracing of pulmonary prosthesis doppler illustrating mean pressure gradient (MPG), peak pressure gradient (PPG) and peak velocity (PV) of prosthesis. b Calculation of Doppler velocity index by dividing right outflow tract (RVOT) VTI to pulmonary valve VTI c Obtaining acceleration time of mechanical prosthesis
Fig. 3 Study population selection flowchart, PVR: pulmonary valve replacement