Abstract Body (Do not enter title and authors here):
Introduction:
Migration of a transcatheter aortic valve replacement (TAVR) is a rare, life-threatening complication that typically occurs during or shortly after the procedure. We present a unique case of an exceptionally rare, delayed migration of a valve-in-valve TAVR three years post-procedure that was subsequently treated with surgical explantation of the TAVR prosthesis and surgical aortic valve replacement (SAVR).

Clinical Case:
A 64-year-old male presented to an outpatient cardiology visit with one month of exertional dyspnea and near-syncopal episodes with a new diastolic murmur. Notable history included aortic regurgitation due to bicuspid aortic valve resulting in subcoronary implantation of a 27 mm Medtronic Freestyle stentless porcine bioprosthesis 20 years prior to presentation. Following the development of severe bioprosthetic regurgitation, a valve-in-valve TAVR with a 26 mm Edwards SAPIEN 3 Ultra was implanted 3 years prior to presentation with no evidence of stenosis or regurgitation on transthoracic echocardiograms completed 1 month and 1 year after implantation. Transesophageal echocardiogram now demonstrated migration of the TAVR valve into the left ventricular outflow tract 2 cm proximal to the surgical bioprosthesis. Severe eccentric transvalvular regurgitant flow through the surgical bioprosthesis and severe paravalvular regurgitation around the TAVR valve was seen with an unstable “rocking appearance”. No evidence of abscess or endocarditis was appreciated and blood cultures showed no growth. Following a short hospitalization, the patient underwent TAVR explantation and implantation of a 25 mm Edwards Inspiris Resilia stented bovine bioprosthesis with subsequent resolution of his symptoms.

Discussion:
Recognizing atypical presentations of TAVR complications such as delayed valve migration is facilitated by understanding key risk factors. This case highlights notable risk factors for TAVR migration including a valve-in-valve TAVR over a degenerative regurgitant bioprosthesis, decreased aortic annulus calcification resulting in suboptimal anchoring, the patient’s younger age, and the lack of a radiopaque marker on the stentless bioprosthesis which increases the potential for malpositioning.