Aims: To study the feasibility and safety of the non-metallic, repositionable and retrievable percutaneous Direct Flow Medical (DFM) aortic valve.
Methods and results: The first-generation (22 Fr) DFM valve has been evaluated in a prospective non-randomised trial in 31 high-risk patients with severe symptomatic aortic stenosis. The procedural success rate was 71%, 30-day mortality 12.9%. Survival at three years was 60% and all patients had none/trace aortic regurgitation at three years. Based on the initial experience, an 18 Fr device has been developed with several important revisions to improve the efficacy and safety of the procedure. Currently, it is being evaluated in a multicentre non-randomised trial which will include 100 patients. The primary endpoint is freedom from all-cause mortality at 30 days.
Conclusions: The 22 Fr DFM valve has been successfully assessed in a first-in-man feasibility and safety trial. Up to three-year follow-up sustained clinical benefit and haemodynamic performance was demonstrated with no or trace aortic regurgitation in all patients. The 18 Fr DFM valve is under investigation in an on-going trial.