Transcatheter Aortic Valve Replacement: Outcomes, Indications, Complications, and Innovations

Transcatheter aortic valve replacement (TAVR) has become the standard of care for the treatment of severe aortic stenosis in individuals who are at prohibitive surgical risk and presents a viable alternative to surgery in selected patients who are at high operative risk. To date, outcomes from the PARTNER (Placement of AoRtic TraNscathetER Valve) and Medtronic CoreValve® US Pivotal trials continue to show the benefits of TAVR in these high-risk subgroups out to 5 and 3 years, respectively (as reported by Mack et al. Lancet. 85:2477-2484 2015; Kapadia et al. Lancet. 385:2485-2491 2015; Deeb et al. J Am Coll Cardiol. 67:2565-2574 2016). Furthermore, the recent release of the PARTNER-2 and SURTAVI trial results among other international data suggest that clinical outcomes for intermediate risk patients may be promising for TAVR compared to surgical aortic valve replacement (SAVR) (as reported by Leon et al. N Engl J Med. 374:1609-1620 2016; Reardon et al. N Engl J Med. 376:1321-1331 2017). However, several questions persist regarding TAVR-specific complications as well as long-term durability. Paravalvular regurgitation, permanent pacemaker implantation, stroke, vascular access injury, and renal failure in post-TAVR patients remain adversaries in the quest to perfect this groundbreaking, game-changing technology (as reported by Khatri et al. Ann Intern Med. 158:35-46 2013). In this review, we provide an up-to-date synopsis of results from landmark clinical trials that cumulatively attest to the comparability of TAVR to best medical therapy and SAVR in extreme-risk, high-risk, and intermediate-risk patient populations. We continue with a review of studies that seek to compare transcatheter vs. surgical valve implantation in lower-risk subgroups. We also introduce ongoing efforts to optimize the peri-procedural management of TAVR and conclude with a presentation of management strategies and new generation valve platforms that seek to address some of the current limitations of transcatheter valve implantation.