Transcatheter implantation of a bovine valve in pulmonary position - A lamb study

Background-Pulmonary regurgitation can lead to severe right ventricular dys function, which is a delicate postoperative problem in the long-term follow -up of patients who had surgery for congenital heart diseases. Clinical con ditions of patients suffering from pulmonary valve incompetence are improve d by valve replacement with a prosthetic valve. To date, the surgical appro ach is the only option to replace a pulmonary valve. We report the first ex perience of percutaneous pulmonary valve implantation. Methods and Results-A fresh bovine jugular vein containing a native valve w as sutured into a vascular stent and then cross-linked with a 0.6% glutaral dehyde solution for 36 hours. After being hand-crimped onto a balloon cathe ter, the device was inserted percutaneously according to standard stent-pla cing techniques. The valved stent was finally deployed in the position of t he native pulmonary valve of the lamb. Hemodynamic evaluation was carried o ut before and 2 months after implantation. Anatomic evaluation was finally performed. Percutaneous pulmonary valve replacement was successful in 5 lam bs. No complications were noted. Early and late angiographic and hemodynami c studies confirmed a good position of the stents with a competent valve at the end of the protocol. One stent was slightly stenotic, with macroscopic ally visible calcifications. Conclusion-Nonsurgical implantation of pulmonary valves is possible in the lamb. This new technique is similar to standard stent implantation. Thus, i t should be feasible in humans, in whom it will lead to a significant reduc tion of reoperations in patients in need of pulmonary valve replacement.