The Lotus valve system (Boston Scientific, Marlborough, Massachusetts, USA) consists of a braided wire Nitinol™ frame with three bovine pericardial leaflets. The valve is deployed by controlled mechanical expansion which allows recapturing/repositioning and full retrievability. Areas covered: While this system offers a unique seal, which conforms to irregular surfaces, thereby minimizing paravalvular leak, its main downfall is a high rate of new pacemaker implantation. This had been partially addressed with the design of the Depth Guard™ mechanism to optimize deployment by early anchoring and limiting the depth of implant. Further developments in the Lotus valve's structure and design lay the foundations for the new Lotus Edge™ valve which is designed to maintain the benefits of the first-generation of the device, while improving deliverability and optimizing deployment with the aim to reduce pacemaker implantation rates. Expert commentary: Data from clinical trials show that TAVI with the Lotus valve system is associated with low rates of all-cause mortality and paravalvular leak although with high rates of permanent pacemaker requirement. Therefore, continuing modifications in device design such as the Lotus Edge™ valve with the addition of the Depth Guard™ are highly awaited with a view to decrease pacemaker rates.
Keywords: TAVI; TAVR; aortic stenosis; mechanical expansion; pacemaker; paravalvular leak.