91Transcatheter valve-in-valve versus redo surgical aortic valve replacement for the management of failed biological prosthesis: early and late outcomes

Abstract

Abstract Background While the gold standard for the management of failed previous biological prosthesis was redo surgical aortic valve replacement (SAVR), valve-in-valve (ViV) transcatheter AVR (TAVR) has emerged as a less invasive option. Published studies comparing the two techniques have been small and limited to early outcomes. Herein, we compare early mortality, morbidity and late mortality between ViV TAVR and redo SAVR. Methods Clinical and administrative databases for Canada's most populous province, Ontario (>13 million patients), were linked to identify patients undergoing ViV and redo SAVR for a failed biological prosthesis. Baseline characteristics were compared and 1:1 propensity score matching (PSM) was performed to account for baseline differences. Standardized mean differences (SMD) were used to assess adequacy of PSM, whereby a SMD<0.10 indicated a good match. Early outcomes were compared in the matched groups using McNemar's test. In accordance to government privacy legislation, outcomes with <6 events, were presented as absolute risk difference (ARD) between ViV and Redo SAVR to prevent patient re-identification. Late mortality was compared between the matched groups using Kaplan-Meier survival curves and a Cox-proportional hazard model. Results Records of 558 patients undergoing intervention for a failed biological prosthesis between March 2008 to September 2017 in 11 Ontario institutions were reviewed (ViV = 214, redo SAVR = 344). Patients who underwent ViV were older (78.2±8.2 vs 69.1±11.4, p<0.001, SMD=0.92) and had more hypertension, diabetes, ischemic heart disease, atrial fibrillation, congestive heart failure compared to redo SAVR before PSM (SMD>0.20). Propensity matching on 24 variables yielded similar groups for comparison (n=133 pairs). Ages were similar between ViV and Redo SAVR (76.0±6.2 vs 76.0±8.7, SMD=0.003) along with all other comorbidities (SMD<0.1). 30-day mortality was significantly lower with ViV compared to Redo SAVR (ARD: −7.4%, 95% confidence interval (95% CI): −12.4%, −2.3%). The rate of permanent pacemaker implantation (ARD: −8.1%, 95% CI: −14.2%, −2.1%), blood transfusions (ARD: −62.2%, 95% CI: −75.2%, −49.1%) and length of stay (LOS) (mean difference: −7.8 days, 95% CI: −11.0, −4.6 days) were also lower with ViV. All-cause mortality at 5 years was similar between ViV and redo SAVR (Figure, p=0.19). Figure 1 Conclusion ViV TAVR was associated with lower early mortality, risk of permanent pacemaker implantation, any blood transfusion, and hospital LOS compared to redo SAVR in the largest PSM study to date. While there was no difference in late mortality at 5 years, additional studies with more subjects and longer follow-up are necessary. ViV TAVR may be the preferred approach for the treatment of failed biological prosthesis.