A new technique to implant a transcatheter inflatable, fully repositionable prosthesis in aortic stenosis with severe asymmetric calcification

In contrast to stented transcatheter aortic valves, the Direct Flow Medical (DFM) valve is a stentless bovine aortic bioprosthesis mounted in a non-metallic inflatable frame. Hence, severe asymmetric annular calcification may result in residually elevated transaortic pressure gradients after DFM implantation. We present a novel intraprocedural dilatation (IDIL) technique for successful implantation of the DFM valve in the presence of complex annular calcification. Between January 2014 and May 2015, 55 patients underwent DFM valve-based transcatheter aortic valve implantation at our institution. Of these, 5 patients required an IDIL technique due to a residual intraoperative transaortic pressure mean gradient above 15 mmHg. The mean patient age was 73 ± 8.2 years; the mean logistic EuroSCORE was 24.5 ± 8.2% and the mean Society of Thoracic Surgeons score was 6.3 ± 4.3%. The IDIL technique immediately attenuated transvalvular mean pressure gradients from 20 ± 2 mmHg to 6 ± 1 mmHg. The results remained stable during the 30-day observation period at 10 ± 3 mmHg. Minimal paravalvular aortic regurgitation (trace) was detected in 2 patients. No in-hospital deaths were observed. The IDIL technique facilitates safe DFM valve implantation in patients with complex asymmetric annular calcification without adverse side effects on valve structure or performance in short-term follow-up.