Off-pump pulmonary valve implantation of a valved stent with an anchoring mechanism.

PURPOSE: The purpose of this study was to evaluate the longitudinal performance and anti-migration effect of a bovine valved stent equipped with an anchoring mechanism implanted off-pump in the pulmonary position.

DESCRIPTION: Through a delivery system, the bell-shaped pulmonary valved stents were implanted off-pump in the pulmonary valve position into six sheep by the transventricular approach. Hemodynamic, angiographic, and echocardiographic evaluations were carried out before, immediately after, and 2 months after implantation. Macroscopic and radiographic examination were performed for evaluation.

EVALUATION: The valved stents were all successfully implanted off-pump in the pulmonary position on six sheep. Early and late angiographic, echocardiographic, hemodynamic, and macroscopic studies confirmed firm anchoring and good positions of the stents. All valved stents were potent, except one mild stenosis with a 24 mm Hg transvalvular pressure gradient that developed and one mild insufficiency that were discovered at the end of the study.

CONCLUSIONS

Transventricular implantation of the bell-shaped pulmonary valved stents was evaluated during a 2-month period in the sheep in the present study and showed a good structural and functional outcome with no migration.