Redo surgery or valve-in-valve TAVR? Treatment of degenerated bioprosthetic aortic valves

The proportion of biological grafts in all implanted aortic valve prostheses has been increasing continuously in western industrialized nations in recent years. Due to the limited shelf life of biological prostheses, an increased number of patients with prosthetic degeneration require treatment. In this high-risk patient cohort, transcatheter aortic valve replacement (TAVR) using the valve-in-valve (ViV) procedure appears to be an attractive alternative to redo surgical aortic valve replacement (SAVR). In retrospective case series the ViV procedure is characterized by low 30-day mortality, low rates of postprocedural bleeding or kidney injury, and rapid convalescence. However, ViV TAVR is associated with increased postprocedural transvalvular gradients if implanted in bioprostheses of small size. In addition, potentially life-threatening coronary occlusions occur in 3-4% of these procedures. Due to a lack of data on the long-term durability of TAVR prostheses and the disadvantageous hemodynamic results after ViV treatment in small bioprostheses, redo SAVR remains the gold standard for young and low-risk patients as well as for patients with unsuitable anatomy for the ViV procedure. Randomized controlled trials comparing both treatment options are urgently needed to create a broader body of evidence.