Congenital heart disease
Valved stents for transapical pulmonary valve replacement

https://doi.org/10.1016/j.jtcvs.2008.09.024Get rights and content
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Objectives

Pulmonary valve insufficiency remains a leading cause for reoperations in congenital cardiac surgery. The current percutaneous approach is limited by the size of the access vessel and variable right ventricular outflow tract morphology. This study assesses the feasibility of transapical pulmonary valve replacement based on a new valved stent construction concept.

Methods

A new valved stent design was implanted off-pump under continuous intracardiac echocardiographic and fluoroscopic guidance into the native right ventricular outflow tract in 8 pigs (48.5 ± 6.0 kg) through the right ventricular apex, and device function was studied by using invasive and noninvasive measures.

Results

Procedural success was 100% at the first attempt. Procedural time was 75 ± 15 minutes. All devices were delivered at the target site with good acute valve function. No valved stents dislodged. No animal had significant regurgitation or paravalvular leaking on intracardiac echocardiographic analysis. All animals had a competent tricuspid valve and no signs of right ventricular dysfunction. The planimetric valve orifice was 2.85 ± 0.32 cm2. No damage to the pulmonary artery or structural defect of the valved stents was found at necropsy.

Conclusions

This study confirms the feasibility of direct access valve replacement through the transapical procedure for replacement of the pulmonary valve, as well as validity of the new valved stent design concept. The transapical procedure is targeting a broader patient pool, including the very young and the adult patient. The device design might not be restricted to failing conduits only and could allow for implantation in a larger patient population, including those with native right ventricular outflow tract configurations.

Abbreviations and Acronyms

ICE
intracardiac echo
IVUS
intravascular ultrasound
RVOT
right ventricular outflow tract

CTSNet classification

20
21
28
35

Cited by (0)

Supported in part by the Swiss National Science Foundation grant 3200B0-113437, Bern, Switzerland. Materials for Valved Stent assembly were provided by Medtronic International, Tolochenaz, Switzerland.