Transcatheter Pulmonary Valve Replacement: A Current Review

Abstract

Since first reported in 2000, transcatheter (percutaneous) pulmonary valve (TPV) replacement has become an important tool for the management postoperative right ventricular outflow tract (RVOT) dysfunction in patients with congenital heart disease, either as alternative or adjunct to surgery. Implantation of a pulmonary valve for treatment of RVOT obstruction or pulmonary regurgitation without performing open-heart surgery offers obvious appeal, and short-term results from multiple institutions throughout the world support the effectiveness and safety of this therapy. At present, there are two TPV prostheses available in the U.S.: the Medtronic Melody Ò valve is available commercially, and the Edwards Sapien Ò valve is available at limited centers as part of an investigational protocol. Although TPV therapy is likely to have a major impact on the management of postoperative RVOT dysfunction in patients with congenital heart disease or a Ross procedure, the technology is young and there is much that remains to be learned.

Percutaneous pulmonary valve implantation in patients after Ross procedure: role of intravascular ultrasound

“…It is estimated that 4-5% of patients undergoing right ventricle outflow tract stenting are at risk of coronary compression. 1 Serious complications are rare, but have been described; 3,4 therefore cautious exclusion of potential coronary constriction is recommended in every patient undergoing right ventricle outflow tract stenting. Pre-procedural assessment with cardiac MRI and CT can be helpful in assessing the static distance between the outflow tract and the coronary tree.…”

“…Approximately 5% of patients undergoing right ventricle outflow tract stenting are at risk of coronary compression 1 . Exclusion of potential constriction is recommended and potential oversight may be fatal 2 .…”

“…Approximately 5% of patients undergoing right ventricle outflow tract stenting are at risk of coronary compression. 1 Exclusion of potential constriction is recommended and potential oversight may be fatal. 2 At times, the suggested methodballoon inflation in right ventricle outflow tract with simultaneous aortography or selective angiographycan be inconclusive or falsely negative.…”

Thermal treatment of expanded polytetraflu-oroethylene (ePTFE) membranes for reconstruction of a valved conduit1

“…The use of polymer to produce flexible leaflet valve has long been a focus of research since 1950s [2]. As a polymer, the ePTFE membranes were firstly reported as a valve material in an animal trail [3], and thereafter have been applied as pulmonary valve for pediatric patients [4], chordae tendineae for mitral valve repair [5,6] and heart valves in right ventricular outflow tract reconstruction (RVOT) operations [7,8]. The benefit of using ePTFE is that it provides a better modulus match than most continuous polymers for many soft biological tissue application [9], easier availability, higher biocompatible and resistance to degeneration or calcification [4].…”

Use and Performance of the Melody Transcatheter Pulmonary Valve in Native and Postsurgical, Nonconduit Right Ventricular Outflow Tracts

“…However, the magnitude of this impact has been tempered by limitations inherent to this new technology, including delivery system and valve size, the durability of the stent supporting the valve, and the suitability of current TPVs to complex ventricular outflow tracts. 1 In addition, the Melody TPV is approved exclusively for use in dysfunctional, circumferential, surgically placed right ventricle-to-pulmonary artery conduits that were equal to or greater than 16 mm when originally implanted, an indication present in only a small proportion of the patients who would clinically benefit from restoration of a functional right ventricular outflow tract (RVOT), including many who are either poor or nonsurgical candidates.…”