Subclinical Structural Valve Degeneration in Young Patients With Bioprosthetic Aortic Valves

Background: Bioprosthetic structural valve degeneration (SVD) has previously been a clinical diagnosis, but subclinical changes have been increasingly recognized in transcatheter valves. The significance of subclinical SVD after surgical aortic valve replacement (SAVR), however, is not well understood. The purpose of this study was to characterize the incidence and outcomes of subclinical SVD in young patients after SAVR. Methods: Patients aged ≤65 years who underwent bioprosthetic SAVR between January 2002 and June 2018 at a single institution were included. Endocarditis cases and those with in-hospital mortality were excluded. All available longitudinal postoperative echocardiograms were reviewed. Subclinical SVD was defined as an increase in mean transvalvular gradient of at least 10 mm Hg and/or new onset of mild intraprosthetic regurgitation or increase by at least 1 grade, compared with baseline postoperative echocardiogram. Results: Overall, 822 unique SAVR cases were included. Over the study period, 356 (43.3%) patients developed subclinical SVD. Only 21.5% of those with subclinical SVD progressed to clinical SVD or to repeat aortic valve procedures. In those with progression, the first signs of SVD occurred significantly earlier than in those whose changes remained stable (11 months vs 23 months; P = .036). Anticoagulation did not impact the development or progression of subclinical SVD. There was no difference in long-term survival for those who did or did not develop subclinical SVD. Conclusions: Subclinical SVD occurred in a large proportion of young patients undergoing bioprosthetic SAVR. Despite its high prevalence, subclinical SVD was not associated with decreased survival or repeat procedures.