Estimated cumulative risk curves in the PARTNER 2 non-inferiority trial.
The PARTNER 2 trial tested for the non-inferiority of trans catheter aortic valve replacement (TAVR) against surgical replacement in intermediate-risk patients with severe aortic stenosis. The primary endpoint was death from any cause or disabling stroke at 2 years. The upper bound of the 95%CI for the HR fell below the non-inferiority margin, leading to a conclusion of non-inferiority. In each group, the RMST measures the average number of months alive and free of disabling stroke over 2 years. The difference in RMST (the area between the curves) measures the difference in 2-year life-expectancy associated with TAVR as compared to surgical replacement, a gain of 18 days over 2 years. The lower bound of the 95%CI for the difference in RMST fell above the respective non-inferiority margin, resulting in a consistent conclusion of non-inferiority.