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Updated: Sep 28, 2026

Protocol for Relative Hydrodynamic Assessment of Tri-leaflet Polymer Valves
Published on: October 17, 2013
Fan-shaped expanded polytetrafluoroethylene valve in the pulmonary position
M Yamagishi1, H Kurosawa, K Nomura
1Department of Pediatric Cardiovascular Surgery Children's Research Hospital, Kyoto Prefectura University of Medicine, Kyoto, Japan. myama@koto.kpu-m.ac.jp
Background:
Residual pulmonary insufficiency remains a problem after transannular repair in pediatric patients. We have developed fan-shaped monocuspid and bicuspid valves made of expanded polytetrafluoroethylene (ePTFE) membrane for repair of right ventricular outflow tract obstruction in patients with tetralogy of Fallot.
Methods:
We studied 20 patients (mean age, 39.6 months) with tetralogy of Fallot. The right ventricular outflow tract was reconstructed with use of a short, wide transannular patch and a fan-shaped valve made of 0.1-mm-thick expanded ePTFE membrane (PRECLUDE Pericardial Membrane, W.L. Gore & Associates, Inc, Flagstaff, AZ). The width of the valve and the outflow patch were constructed so that the neopulmonary annulus was approximately 130% the normal size.
Results:
A monocuspid valve was used in 17 patients and a bicuspid valve in 3. The mean follow-up time was 32.3 months (range, 14.7 to 56.7 months). Right ventricular function was well maintained in all patients. Valvular motion remained competent in 13 patients (65%). In the remaining 7 (35%), the valve became fixed in the open position. Trivial and mild pulmonary insufficiency was detected in 10 patients with a competent valve and 7 with an incompetent valve. No pressure gradient across the neopulmonary annulus or calcification of the expanded ePTFE membrane was detected in any patient.
Conclusions:
The fan-shaped expanded ePTFE valve is a useful substitute with adequate function in transannular right ventricular outflow reconstruction.
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