Early Hemodynamic Profile after Aortic Valve Replacement — A Comparison between Three Mechanical Valves
"Abstract
Introduction: There are scarce data comparing different
mechanical valves in the aortic position. The objective of this study
was to compare the early hemodynamic changes after aortic valve
replacement between ATS, Bicarbon, and On-X mechanical valves.
Methods: We included 99 patients who underwent aortic valve
replacement with mechanical valves between 2017 and 2019. Three
types of mechanical valves were used, On-X valve (n=45), ATS AP360
(n=32), and Bicarbon (n=22). The mean prosthetic valve gradient was
measured postoperatively and after six months.
Results: Preoperative data were comparable between groups,
and there were no differences in preoperative echocardiographic
data. Pre-discharge echocardiography showed no difference
between groups in the ejection fraction (P=0.748), end-systolic
(P=0.764) and end-diastolic (P=0.723) diameters, left ventricular mass
index (P=0.348), aortic prosthetic mean pressure gradient (P=0.454),
and indexed aortic prosthetic orifice area (P=0.576). There was no
difference in the postoperative aortic prosthetic mean pressure
gradient between groups when stratified by valve size. The changes
in the aortic prosthetic mean pressure gradient of the intraoperative
period, at pre-discharge, and at six months were comparable between
the three prostheses (P=0.08). Multivariable regression analysis
revealed that female gender (beta coefficient -0.242, P=0.027), body
surface area (beta coefficient 0.334, P<0.001), and aortic prosthetic
size (beta coefficient -0.547, P<0.001), but not the prosthesis type,
were independent predictors of postoperative aortic prosthetic mean
pressure gradient.
Conclusion: The three bileaflet mechanical aortic prostheses
(On-X, Bicarbon, and ATS) provide satisfactory early hemodynamics,
which are comparable between the three valve types and among
different valve sizes.
.... The change in aortic prosthetic pressure gradient over the four-time points was significant across all prosthetics types where the mean gradient decreased significantly after valve replacement and then increased significantly from the intraoperative period to pre-discharge and then at six months (P<0.001) . The small but statistically significant increase in the aortic mean pressure gradient at discharge and at the six-month follow-up TTE compared to intraoperative TEE is likely related to changes in hemodynamics and loading conditions.
https://cdn.publisher.gn1.link/bjcvs.org/pdf/0102-7638-rbccv-2020-0273.pdf