Long-Term Durability of Transcatheter Valves: The Importance of Accurate Data

As transcatheter valves are offered to progressively lower-risk patients, it is increasingly important to have accurate data about durability. Structural valve deterioration (SVD) implies an adverse change in the morphology of the leaflets and function of the valve compared with the state at implantation. However, a recent European statement allows SVD to be defined solely by a threshold mean gradient ≥20 mm Hg. Absolute mean gradients above this threshold may be observed immediately after implantation and represent patient–prosthesis mismatch and not SVD. This paper describes a definition of SVD more in keeping with routine clinical practice, incorporating a change in leaflet morphology and an increase in the grade of transvalvar regurgitation or an increase in gradient from the post-implantation study.