Comparison of multicenter registries and randomized control trials for transcatheter aortic valve replacement (TAVR)

Background: TAVR has emerged as an attractive alternative for treatment of severe aortic stenosis in high risk surgical patients. Despite several large multicenter registries, only one randomized trial (PARTNER) has been published.

Objective: We aimed to compare the outcomes obtained using multicenter registries and the PARTNER trial.

Methods: Standard MEDLINE search strategy was used to find multicenter registries, reporting clinical outcomes following TAVR. Meta-analytic techniques were utilized to calculate pooled outcomes across multicenter registries and compare them to outcomes in PARTNER trial.

Results: Pooled 30-day mortality rate from the registries was 9.2%, which was significantly higher than that in the PARTNER trial (3.8%). Medium-term mortality rates were similar between the PARTNER trial and the multicenter registries. Pooled 30-day and 1-year stroke rates in multicenter registries were 2.6% and 3.8%, respectively. On the other hand, the corresponding rates in PARTNER trial were 5.2% and 7.6%, respectively. In the registry-related cohorts, pooled 30-day and 1-year mortality rates were 6.8% and 20.8% in the transfemoral group and 12.2% and 32.2% in the transapical group. In the PARTNER trial, the pooled incidence of 30-day and 1-year mortality rates were 3.9% and 26.2% in the transfemoral group and 3.8% and 29.0% in the transapical group.

Conclusions: Short-term results in PARTNER were better than those reported in the registries, which may be due to better patient selection and aggressive bailout techniques. Similarity of medium-term outcomes between registries and PARTNER highlights that patient selection for TAVR is critical due to considerable risk of mortality in the first year even after the successful procedure.