ABSTRACT Introduction: The impact of mitral regurgitation (MR) on valve-in-valve transcatheter aortic valve implantation (VIV-TAVI) in patients with failed bioprostheses remains unclear. The purpose of this study was to assess the prognostic impact of residual moderate MR following VIV-TAVI. Methods: We retrospectively analyzed 127 patients who underwent VIV-TAVI between March 2010 and November 2021. At least moderate MR was observed in 51.2% of patients before the procedure, and MR improved in 42.1% of all patients. Patients with postoperative severe MR, previous mitral valve intervention, and patients who died before postoperative echocardiography were excluded from further analyses. The remaining 114 subjects were divided into two groups according to the degree of postprocedural MR: none-mild MR (73.7%) or moderate MR (26.3%). Propensity score matching yielded 23 pairs for final comparison. Results: No significant differences were found between groups before and after matching in early results. In the matched cohort, survival probabilities at one, three, and five years were 95.7% vs. 87.0%, 85.0% vs. 64.5%, and 85.0% vs. 29.0% in the none-mild MR group vs. moderate MR-group, respectively (log-rank P=0.035). Among survivors, patients with moderate MR had worse functional status according to New York Heart Association (NYHA) class at follow-up (P=0.006). Conclusion: MR is common in patients with failed aortic bioprostheses, and improvement in MR-status was observed in over 40% of patients following VIV-TAVI. Residual moderate MR after VIV-TAVI is not associated with worse early outcomes, however, it was associated with increased mortality at five years of follow-up and worse NYHA class among survivors.

Abstract Introduction: Transcatheter aortic valve-in-valve implantation (TAVI-ViV) can be associated with unfavorable hemodynamic outcomes. This study aimed to estimate the prevalence, identify the risk factors, and evaluate the outcomes and survival of patients with high residual gradients after TAVI-ViV. Methods: A total of 85 patients were included in the study. The cohort was divided into group A, with postprocedural mean pressure gradient (PG) ≥ 20 mmHg, and group B, with mean PG < 20 mmHg. Results: Postprocedural PG ≥ 20 mmHg was observed in 24.7% of the patients. In a univariate analysis, preoperative gradient, pre-existing patient-prosthesis mismatch (PPM), deep valve implantation, small degenerated valves, and an older generation of transcatheter aortic valves were found to be risk factors for high residual gradient. Multivariate analysis showed that preexisting maxPG > 60 mmHg, implantation level of 4 mm below neo-annulus, and degenerated valve size ≤ 23 mm were independent predictors of high residual gradient. There were no differences in early morbidity (myocardial infarction, pacemaker implantation, stroke, acute renal insufficiency) between groups. Kaplan-Meier estimated that the survival rate was comparable at one and five years regardless of postoperative gradient. Survivors with high residual mean gradient were significantly affected by a high New York Heart Association (NYHA) class. Conclusion: High residual transvalvular gradient after TAVI-ViV is not rare, but it does not significantly affect mortality. High residual mean gradient has a negative impact on NYHA functional class improvement after the procedure. High preoperative gradient, implantation level, and small failed bioprosthesis may predispose to increased residual gradient.