Pharmacologie cardiovasculaire : libre accès

Abstrait

Expandable Polyurethane Stent Valve, implanted by catheter, in pediatric and adult patients: Results from physical, hydrodynamic, animal and ultrastructural Studies

Miguel A. Maluf

Background: Patients with pediatric prostheses suffer from mismatch and early calcification, which causes a high number of reoperations

Methods: Expandable Polyurethane Stent Valve – EPSV, is composed by a flexible polyurethane (PU) leaflets is grown on the top of an expandable cobalt-chrome alloy stent, including the formation of three leaflets. Physical, hydrodynamic, animal studies, were performed following: ISO 5840-3, 2015.

Results: Physical tests. Result of study of surface scanning of pre and post crimp stent, showed no structural modification of the PU. Hydrodynamic test showed a pressure gradient oscillation between 5 to 20mm, in basal or stress condition respectively. Experimental studies. Sheep were subjected to 3D echo-Doppler study, in 6^th follow-up months, which showed satisfactory hemodynamic performance, with low transvalvular   gradient (M = 6.60 mm Hg).

Ultrastructural Study: Six stents were explanted after 20 days to 21 months of follow-up to Ultrastructural analysis. All of which revealed no presence of calcium growth and prostheses structure was intact.

Conclusions: Expandable Stent valve and PU no Calcification are good expectations for pediatric use.