Transapical aortic valve implantation: learning curve with reduced operating time and radiation exposure

BACKGROUND: The purpose of this study was to test whether, and in which terms, the cumulative institutional experience in the field of transapical transcatheter aortic valve implantation (TAVI) might impact upon operative time and radiation exposure. METHODS: This was a retrospective, single-center, observational cohort study of prospectively collected data from all 500 consecutive high-risk patients undergoing transapical TAVI at our institution between April 2008 and December 2011. Differences during the study period in baseline characteristics, procedural and post-procedural variables, and survival were analyzed. Nonparametric correlation and linear regression analyses were used to identify changes in operative time, contrast agent use, and radiation exposure according to institutional cumulative experience. RESULTS: Median operating time was 90 minutes (interquartile range 75-115 min) and fluoroscopy time was 6.7 minutes (4.8-10.3 min). Combined planned percutaneous coronary intervention was performed in 57 (11.4%) patients. There was a significant correlation between operating time, fluoroscopy time, and institutional experience. A 5% reduction in operating time (95% CI 3% to 8%, p < 0.0001) and 15% reduction in radiation exposure time (95% CI 12% to 18%, p < 0.0001) was reported per 100 procedures performed. CONCLUSIONS: After introduction and implementation of a structured training program for transapical TAVI, operating time and radiation exposure are contained and reduced over the entire observation time in 500 consecutive patients