Page 15 - Journal of Structural Heart Disease Volume 1, Issue 3

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Original Scientific Article
mounted within the nitinol stent. This valve has a sim- ilar leaflet thickness to conventional surgical porcine tissue valves because the design does not require excessive “crimping” of the leaflets. To minimize PV- AR, a polyethylene terephthalate skirt is mounted at the proximal (intra-annular) part of the stent body. The delivery system is based on a sheathless concept similar in size to a 28 Fr sheath system. Valve deploy- ment is facilitated using a simple rotational knob suitable for a single-operator technique. Until final release the system allows for resheathing and reposi- tioning. Three different sizes (labeled small, medium and large) are available allowing for treatment of pa- tients presenting with an annulus diameter ranging from 20–27 mm. A transfemoral version of this device called ACURATE TF is very similar to the ACURATE TA device [36]. A 20 Fr delivery system has a flexi- ble shaft facilitating easy tracking even in tortuous aortic anatomy. It allows a controlled three-step im- plantation of the prosthesis. There is also a newer transfemoral version called ACURATE neo that has a 15 Fr compatible delivery system.
The results of a first-in-human trial in 40 patients that underwent ACURATE TA implantation including 6 month follow-up have been published [35, 37]. De- vice success rate was 92.5%, mean transaortic gra- dient was reduced from 51.9 ±14.3 mm Hg to 11.9 ± 5.8 mm Hg. Thirty-day mortality was 12.5% and major stroke rate was 5%. At 6 months, only 3.3% of patients had more than mild PV-AR. Similar out- come have been published recently in a series of 62 patients [38]. A first-in-human trial in 20 patients treated with the ACURATE TF device has also been published [36]. The effective orifice area improved from 0.7 cm2 to 1.8 cm2 and only one patient had a grade 2 PV-AR. Procedural success rate was 95% with one case of stroke, and two pacemaker implanta- tions at 30 days. ACURATE TA device has a CE mark obtained at 2011 and ACURATE neo device has a CE mark obtained at 2014.
Medtronic Engager
The Engager Aortic Valve bioprosthesis (Medtronic, Minneapolis, MN, USA) is a biological valve prosthesis composed of three leaflets cut from tissue-fixated bovine pericardium, sewn to a polyester sleeve and mounted on a compressible and self-expanding niti-
Figure 15: The Engager Aortic valve bioprosthesis. A self- expandable valve composed of three leaflets cut from tissue- fixated bovine pericardium, sewn to a polyester sleeve and mounted on a nitinol frame.
nol frame [39] (Figure 15). The stent assembly consists of a shaped main frame and a support frame, which are coupled together so as to form the commissur- al posts of the valve. Two types of sewing materials are used: polyester and expanded polytetrafluoro- ethylene. The valve design is intended to minimize PV-AR. The prosthesis is available in two sizes (23 mm and 26 mm) covering annulus diameters from 21 to 27 mm [40]. To achieve an anatomically correct posi- tion and to minimize the risk of coronary obstruction, the side arms fixed at the main frame of the prosthe- sis are designed to be placed into the sinuses of the aortic root. The valve can be repositioned before final deployment. Implantation is performed transapically with an over-the-wire delivery system comprising an introducer and a flexible delivery catheter which form one integral unit. The delivery system is composed of a 29 Fr (inner diameter) introducer and a flexible de- livery catheter with a 13 Fr shaft. Engager valve has a CE mark for treatment of patients with AS since 2013.
Abramowitz, Y. et al.
TAVR Devices