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Updated: Jan 21, 2026

Transcatheter Pulmonary Valve Replacement from Autologous Pericardium with a Self-Expandable Nitinol Stent in an Adult Sheep Model
Published on: June 8, 2022
A stented bovine pericardial prosthesis in the pulmonary position
Hanna Pragt1, Mirthe H Schoots2, Ryan E Accord1
1Department of Cardiothoracic Surgery, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
Background:
Pulmonary valve replacement is very common among patients with congenital heart disease. The Carpentier Edwards Perimount valve (Edwards Lifesciences, Irvine, Calif), which was originally designed for the aortic position is among the most implanted valves. We aim to describe the follow-up of this valve in the pulmonary position.
Methods:
Patients with a Perimount valve implanted between 2003 and 2013 in the University Medical Center Groningen were followed for the primary end point reintervention, defined as surgical or transcatheter valve replacement. Secondary end point was the occurrence of valve failure, defined as significant valvular regurgitation or stenosis. Explanted valves were histologically examined.
Results:
Forty-five patients (median age at operation 27.8 years, 55.6% women) had a mean follow-up duration of 5.8 ± 3.3 years. There were 7 reinterventions (5 surgical and 2 transcatheter). Freedom from reintervention was respectively 95% ± 4% and 83% ± 8% at 5- and 10- years of follow-up. Freedom from valve failure was 75% ± 4% at 2 years, 65% ± 8% at 5 years of follow-up and 57% ± 10% at 10 years of follow-up. Morphology evaluation (n = 4) showed stiffened valves in the open position, with extensive fibrous tissue overgrowth on the leaflets and a variable proliferation of myofibroblasts.
Conclusions:
The Perimount valve has adequate function in the pulmonary valve position at 5 years of follow-up, although after 10 years of follow-up valve failure and reinterventions are common. Explanted valves show retraction and stiffening of the leaflets due to a fibrotic layer on both sides of the leaflet.
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