Valve degeneration in patients with aortic porcine bioprosthesis evaluated through 18Fsodium fluoride PET

Abstract

Introduction: prosthetic valve degeneration is a relevant clinical disorder; conventional imaging methods allow diagnosis in the later stages. ¹⁸Ffluoride positron emission tomography (PET) can detect subclinical degeneration earlier.

Objective: correlate parameters of prosthetic structural deterioration by PET with echocardiographic hemodynamic parameters one year after aortic valve replacement (AVR) by porcine bioprosthesis.

Methods: prospective ad hoc study of a clinical trial. Patients undergoing AVR by porcine bioprosthesis were recruited in two national centers between 01/01/2019 and 02/13/2020. Clinical and echocardiographic controls were carried out. 19 subjects were randomly selected and underwent ¹⁸Fsodium fluoride PET with CT angiography one year after AVR. Tracer uptake in the valve (SUVavV) and right atrium (SUVavA) was measured, creating the SUVavV/SUVavA index, which was compared with the mean and maximum gradients at one year, using Spearman’s correlation analysis.

Results: of a total of 140 subjects, PET was performed on 19 at 16.3 months (15.9-16.9) after the AVR. The median SUVavV/SUVavA ratio was 1.17 (1.11-1.27). A moderate negative correlation was found between. ¹⁸Ffluoride uptake and the mean gradient (correlation coefficient -0.516, p = 0.028) and maximum (coefficient of -0.589, p = 0.010) at one year.

Conclusions: we found low uptake values in PET, echocardiographic gradients in normal range and no positive correlation between both parameters. It is the first national report with these imaging techniques.