Improving outcomes: case-matched comparison of novel second-generation versus first-generation self-expandable transcatheter heart valves

OBJECTIVES: The published literature has extensively documented clinical benefit derived from transcatheter aortic valve implantation (TAVI) in high-risk patients using self-expanding current-generation transfemoral (TF) transcatheter heart valves (THVs). However, it has also demonstrated apparent shortcomings such as paravalvular leakage (PVL) or need for permanent pacemaker (PM) implantation. We here present a case-matched analysis of acute 30-day outcomes using a novel nitinol-based THV (Symetis Acurate Neo TF™), which may overcome some limitations of currently used devices.

METHODS: From 2012 to 2015, 69 consecutive patients (study group, 65.2% female, 81.4 ± 6.1 years, logEuroSCORE I 19.9 ± 14.2%) received TF-TAVI using the novel Symetis Acurate Neo TF™ THV. A control group of patients after TF-TAVI with the CoreValve™ THV was retrieved from our database (control group) and matched to the study group utilizing 16 parameters. Data were retrospectively analysed according to updated Valve Academic Research Consortium (VARC-2) definitions. The 30-day follow-up was completed in all cases.

RESULTS: Apart from gender (65.2 vs 44.9% females, P = 0.023), matching was successful with parameters showing no significant differences. The device success rate was 95.6% (66/69) and 89.9% (62/69) in the study and control groups, respectively (P = 0.20). The all-cause 30-day mortality rate was 5.8% (4/69) vs 10.14% (7/69) (P = 0.36), and disabling stroke was observed in 2.9% (2/69) vs 5.8% (4/69) (P = 0.41), respectively. Resultant transvalvular maximum/mean gradient and effective orifice area (EOA) were 13.8 ± 5.5 vs 18.1 ± 8.1 mmHg (P = 0.001)/7.0 ± 2.8 vs 8.8 ± 4.0 mmHg (P = 0.006) and 1.9 ± 0.3 vs 1.8 ± 0.2 cm(2) (P = 0.015), respectively. PVL ≥grade II was observed in 2.9% (2/69) and 15.94% (11/69) (P = 0.013) of patients and the rate of PM implantation was 8.7% (6/69) vs 44.9% (31/69) (P < 0.001), respectively.

DISCUSSION: TF-TAVI was feasible and safe using this new type of nitinol-based THV. Superiority to the current generation of self-expanding THVs was achieved regarding post-interventional pressure gradients and EOA, severity of residual PVL and rate of PM implantation. Results set a promising quality standard for TF-TAVI with a self-expanding THV, but will have to be confirmed in a larger patient cohorts for further clinical evaluation.