The Navitor transcatheter aortic valve (TAV) implanted at low implant depths led to more favorable redo procedures than higher depths and other self-expanding valves (SEV), according to a new simulation. The findings, published online in a JACC: Cardiovascular Interventions research letter, highlight the importance of TAV selection and implant depth by operators during both index and redo-TAV replacement (TAVR) procedures, in order to preserve the feasibility of re-intervention, the researchers said. Experts anticipate a rise in redo TAVR procedures, since younger patients – who may outlive the durability of the index TAV – are now being treated. Redo-TAVR may be unfeasible for some of these patients due to the pinned-up leaflets of the index TAV creating a leaflet neo-skirt that risks compromising coronary flow, according to the letter’s authors, led by Yusuke Kobari, MD, PhD, from the Heart Center Rigshospitalet, Copenhagen, Denmark. “This coronary risk is increased with tall-frame supra-annular [SEV], due to the higher leaflet position creating a taller leaflet neo-skirt,” they noted. Abbott’s Navitor TAV is a tall-frame SEV, but with an intra-annular leaflet design that could reduce coronary risk during redo procedures, the authors said, though stressed that no clinical data is available for this hypothesis. The current study therefore set out to examine the feasibility of redo-TAVR in patients with a degenerated Navitor TAV using Edwards Lifesciences’ balloon-expandable SAPIEN 3 (S3) device in a simulation based on real-world post-TAVR cardiac computed tomography (CT) scans for 106 patients (median age=79 years, 44% female). The implant depth of the index Navitor was measured at each cusp and averaged, and a virtual S3 was implanted inside originator device at 2 different positions; as a ‘low implant’, defined as the S3 outflow being in line with Navitor node 2; and as a ‘high implant’, keeping the S3 outflow in line with the bottom of the Navitor commissure tab. The coronary risk was determined by evaluating the neo-skirt plane (NSP), coronary risk plane (CRP) and valve-to-aorta distances for both coronary ostia. Coronary risk was deemed to be low if the NSP arose below the CRP, and if the NSP rose above the CRP and the valve-to-aorta distance was >4 mm. The risk was tagged as intermediate for NSPs rising above the CRP with valve-to-aorta distance of 2 to 4 mm, and high when <2 mm. Redo-TAVR coronary risk was impacted by the implant depth of the index Navitor, with procedures using a high S3 implant “highly dependent” on the Navitor’s depth. The redo was deemed to be unfeasible for 73% of cases with a high Navitor implant depth, 43% of those with a standard implant depth and 28% of those with a low implant depth. “On the other hand, with a low [S3] implant position, redo-TAVR was deemed feasible for >98% of cases, irrespective of the index Navitor implant depth,” the researchers noted. Coronary risk for redo patients was also impacted by the simulated S3 position, they said, adding that comparisons for this analysis can be drawn with prior studies evaluating S3-in-SEV based on post-TAVR CT scans using an identical methodology. The letter’s authors also said the data suggests redo-TAVR with S3-in-Navitor “compares favorably” to S3-in-ACURATE neo2 (Boston Scientific) and S3-in-Evolut (Medtronic) as “a lower coronary risk is observed irrespective of the S3 implant depth (P < 0.001 for the Bonferroni comparison between all 3 SEVs, with redo-TAVR simulated using a high or low S3 implant position). “These results demonstrate that, although Navitor is a tall-frame SEV, its intra-annular leaflet position creates a shorter leaflet neo-skirt, which has a favorable impact on redo-TAVR feasibility,” they said. “In addition, the tubular inflow stent frame design of the Navitor TAV allows an operator to precisely target a specific implant depth during the index procedure, which can impact future coronary risk and subsequent redo-TAVR feasibility.” Source: Kobari Y, Khokhar AA, Lulic D, et al. Research Letter: Impact of Transcatheter Aortic Valve Design and Implant Strategy on Redo-TAVR Feasibility, A CT-Based Analysis. JACC: Cardiovasc Interv. 2025 April 30; DOI:10.1016/j.jcin.2025.02.026. Image Credit: Studio Romantic – stock.adobe.com