Rethinking percutaneous paravalvular leak closure: where do we go from here?

Paravalvular leak (PVL) is an uncommon yet serious complications associated with the implantation of surgical prosthetic valves and more recently recognized with transcatheter valves. Renewed interest has developed as relationships have emerged between the degree of paravalvular regurgitation and mortality. Percutaneous closure of PVLs has shown significant promise with contemporary success rates as high as 86%, especially in patients at high risk for surgical repair or replacement. Growth in the field of structural heart disease has afforded the adaptation of many technical and procedural advances in an attempt to further improve transcatheter success, while reducing the risk of complications. Recent publications in Revista Española de Cardiologı́a by Cruz-González et al and Sánchez-Recalde et al exemplify the continued desire of interventionalists to innovate. It is their application of newer technologies and techniques that is allowing for expansion. For percutaneous PVL closure, the question remains, where do we go from here? We believe that a 3-fold approach, which focuses on better devices to fit the unique shapes of PVLs, more favorable sites of access, and improved imaging guidance, will further push the limits of this encouraging therapy. PVLs are the result of an incomplete seal between the sewing ring and annulus for surgical prostheses or stent frame and aortic annulus/calcified leaflets for transcatheter aortic valves. For the former, this arises from abnormal pressure or traction forces after surgery, usually related to annular calcification, infection, suturing technique, and prosthetic size and shape. For the latter, PVL is typically a result of incomplete prosthesis apposition to the native aortic annulus due to calcification, annular eccentricity, valve undersizing, and/or malpositioning, irrespective of the prosthesis type: selfor balloon-expandable. Most of our experience in transcatheter closure and imaging revolves around PVLs in the setting of surgical prostheses. Despite the potential etiologies, the shape and track of each PVL varies. It is rare to find round PVL, with most having an oval or crescentic appearance. In addition, their tracks are rarely parallel and often run perpendicular with a