Will There Ever Be a Food and Drug Administration–Approved Device for Transcatheter Paravalvular Leak Closure?

P aravalvular leaks (PVLs) have been a recognized problem after surgical valve replacement since prosthetic valves were first implanted for aortic and mitral valve disease 5 decades ago. 1 Although the reported incidence varies considerably, it is generally estimated that a PVL of some magnitude is present in ≈7% to 17% of mitral and 2% to 10% of aortic valve replacement prostheses.[2][3][4][5] Most PVLs are small and inconsequential, but anywhere from 1% to 5% of aortic or mitral valve replacement procedures are complicated by a clinically relevant PVL.[2][3][4][5] Although the use of transcatheter devices to close prosthetic PVLs was described >20 years ago, 6 this procedure remained relatively rare until recently, but with the availability of nitinol mesh devices designed for occlusion of various other communications, transcatheter PVL closure has become a regular, although still somewhat uncommon, procedure for many structural interventional cardiologists.4,5,[7][8][9][10][11][12] Moreover, as transcatheter aortic valve replacement has become increasingly widespread, and paravalvar regurgitation has been recognized as one of its most frequent and significant complications, 13 an entirely new domain has opened up, namely, management of PVLs after transcatheter aortic valve replacement.Literature on PVL device closure comprises a handful a modest-sized, single-center series and many more single or small case reports.4,5,7,[14][15][16][17][18][19][20] Based on these series, device closure is technically unsuccessful in 5% to 35% of cases, for various reasons, including inability to cross the defect with a wire or delivery catheter, dislodgement/embolization of the device, incomplete closure of the defect, or interference by the device with the prosthetic valve.Even if the device is delivered, remains in place, and reduces flow, the treatment may be clinically inadequate, sometimes because of persistent or new hemolysis, and sometimes for reasons that are less clear.Considering both technical and clinical outcomes, published series have reported success in anywhere from 55% to 77% of patients who undergo closure.Among those in whom these measures of success are met, PVL may not be (Circ