Institutional experience and outcomes of transcatheter aortic valve replacement: Results from an international multicentre registry.

BACKGROUND: Despite rapidly increasing use of TAVR across institutions, limited data is available for the effect of procedural experience on TAVR outcomes. We investigate the relationship between institutional experience and TAVR outcomes.

METHODS: 1953 patients undergoing TAVR at 8 international sites were grouped into chronological quantiles (Q) to assess temporal changes on procedural and clinical outcomes and multivariate logistic regression performed to determine predictors of device success, early safety and all-cause mortality.

RESULTS: The mean age of patients was 81±7years and 991 (51%) were female. The quantiles comprised of first 62 cases for Q1, 63-133 for Q2, 134 to 242 for Q3 and 243 to 476 for Q4. Device success increased from Q1 to Q4 (78% vs 89%, p<0.001) with significant improvement in the early safety endpoint (19% vs 10%, p<0.001). All cause mortality reduced by half in Q4 compared to Q1 (8% vs 4%, p=0.01) and rates of major vascular complications, major bleeding and valve embolization decreased with increasing experience. The multivariate analysis identified TAVR in Q3 and Q4 to be independently associated with higher device success and lower risk of complications. TAVR in Q4 was independently associated with lower mortality (OR 0.36 95% CI 0.19-0.70, p=0.002).

CONCLUSIONS: Greater institutional experience with TAVR procedures improves device success and clinical outcomes. An experience of >242 cases is independently associated with lower mortality. These findings have important implications for defining minimum volume criteria for institutions and training standards for TAVR procedure.