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Updated: Aug 18, 2026

Transcatheter Pulmonary Valve Replacement from Autologous Pericardium with a Self-Expandable Nitinol Stent in an Adult Sheep Model
Published on: June 8, 2022
Is there a role for mechanical valved conduits in the pulmonary position?
Felix Haas1, Christian Schreiber, Jürgen Hörer
1Department of Pediatric Cardiothoracic Surgery, Wilhelmina Children's Hospital, Utrecht, The Netherlands. f.haas@wkz.azu.nl
Background:
The use of allografts or xenografts is the treatment of choice for pulmonary valve replacement. However, the limited durability is responsible for multiple reoperations associated with increased morbidity. In search of a definitive solution, the implantation of a mechanical valved conduit might be an option in highly selected patients. This study evaluated short-term results after pulmonary valve replacement with a mechanical valved conduit.
Methods:
Fourteen patients underwent pulmonary valve replacement with a mechanical valved conduit. All patients had a mean of 3.0 +/- 1.2 previous operations. Seven patients were previously operated on for tetralogy of Fallot, 3 patients for pulmonary atresia, 3 patients for common arterial trunk, and 1 patient for subaortic stenosis.
Results:
All patients survived the operation and are currently well. At follow-up (11 to 63 months), all but 2 patients showed normal right ventricular function, with a mean gradient of 14 +/- 9 mm Hg (range, 4 to 30 mm Hg) across the pulmonary valve. At follow-up, there was no evidence of valve failure or tissue growth within the valve annulus. All patients are receiving anticoagulants to maintain an international normalized ratio of 3.0 to 4.5.
Conclusions:
In highly selected patients, the use of a mechanical valved conduit in the pulmonary position leads to satisfactory results. To avoid a predictable reoperation after multiple right ventricular outflow tract reconstruction, and therefore reoperation-related morbidity, the implantation of a mechanical prosthesis as a lifelong solution requires consideration. Selection criteria for this permanent solution should include older age, multiple previous operations, and patient compliance with anticoagulant therapy.
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