Introducing transcatheter aortic valve implantation with a new generation prosthesis: Institutional learning curve and effects on acute outcomes

OBJECTIVES We present our single-centre experience with the direct flow medical (DFM) trans-catheter aortic valve implantation (TAVI) prosthesis addressing the impact of learning curve upon outcomes. BACKGROUND The DFM has been recently introduced for TAVI. The prosthesis presents original design and implantation features. METHODS Patients were divided into three groups according to the chronological implantation sequence that reflected technical skills acquisition of the entire team. RESULTS Group I included the first 20 patients (early learning phase), group II the second 20 patients (proctoring to other members of the team), and group III the following 93 patients (technique consolidation). Differences in baseline and procedural variables were analysed. Nonparametric correlation and linear regression were used to identify changes according to institutional cumulative experience. There was a significant correlation between catheterisation time and institutional experience (rho = -0.4; p < 0.0001) confirmed at linear regression (beta = -0.2; p = 0.001; CI: -0.3 - -0.08). Moreover, there was lower rate of valve retrieval in group III (15% vs. 20% vs. 10%; p = 0.5). No intra-procedural mortality was reported and improved early safety (at 30 days) was observed (80% vs. 85% vs. 87.1; p = 0.7). At hospital discharge, valve haemodynamic performance was satisfactory with only mild regurgitation in 10% (I), 20% (II), and 9.7% (III) (p = 0.8). CONCLUSIONS DFM adequate sizing and implantation can be achieved after the early learning phases. A significant reduction in catheterisation time is reported after the first 20 patients. Results remain satisfactory during the proctoring and technical consolidation phase.