New technologies aimed at treating aortic stenosis are constantly evolving to reduce risks and address an increasingly comorbid population. Within this context, the sutureless Livanova® Perceval® prosthesis has emerged as a promising alternative. While short-term data has been highly favorable, evidence on mid-term outcomes remains limited. Therefore, this systematic review and meta-analysis represents the first study to specifically assess the isolated mid-term results of the Livanova® Perceval® prosthesis.

In this study, a systematic literature review was conducted across five databases. The selected articles evaluated echocardiographic and mortality outcomes beyond 5 years in patients who underwent aortic valve replacement (AVR) with the Livanova® Perceval® prosthesis. Two reviewers extracted and reviewed the articles. Weighted estimates were made for all postoperative and mid-term data. Aggregated Kaplan-Meier survival curves were reconstructed from digitized images to assess long-term survival. Seven observational studies were identified, analyzing a total of 3,196 patients. Thirty-day mortality was 2.5%. Aggregate survival at 1, 2, 3, 4, and 5 years was 93.4%, 89.4%, 84.9%, 82%, and 79.5%, respectively. The incidence of permanent pacemaker implantation (7.9%), severe paravalvular leak (1.6%), structural valve deterioration (1.5%), stroke (4.4%), endocarditis (1.6%), and valve explantation (2.3%) were within acceptable ranges during the follow-up period. The hemodynamics of this prosthesis also showed favorable mid-term results, with a mean transprosthetic gradient (range 9 to 13.6 mmHg), peak transprosthetic gradient (17.8 to 22.3 mmHg), and effective orifice area (1.5 to 1.8 cm²) across all prosthetic sizes. Cardiopulmonary bypass (78 minutes) and aortic cross-clamp times (52 minutes) were also favorable.

The authors conclude that this is the first meta-analysis to date to evaluate the mid-term outcomes of the Perceval prosthesis independently, demonstrating good mortality, hemodynamic, and morbidity outcomes beyond 5 years.

COMMENTARY:

The importance of this study lies in it being the first meta-analysis evaluating mid-term outcomes (more than 5 years of follow-up) of the sutureless Livanova® Perceval® prosthesis, highlighting its efficacy and safety.

Regarding the primary objective, a 5-year survival rate of 79% was observed, a figure comparable to that found in current literature for conventional prostheses (75%-86%). Another notable finding was the excellent long-term mean transvalvular gradient with this sutureless prosthesis (9-13.6 mmHg), lower than that of conventional prostheses, and comparable to or even better than stentless bioprostheses and transcatheter aortic valve replacements (TAVR).

In terms of complications, the rates of severe periprosthetic leakage (1.6%) and structural valve deterioration (1.5%) were low at mid-term. This suggests that the mid-term performance of this prosthesis is at least comparable to that of conventional prostheses. The incidence of paravalvular leakage was also low (3.6%), slightly worse than that of conventional bioprostheses but better than the reported rates for TAVR (3-25%). Additionally, the reintervention rate due to periprosthetic leaks in this meta-analysis was less than 1%, which is lower than the 3.3% reported in a recent meta-analysis evaluating the Edwards® Intuity® prosthesis. The incidence of stroke and prosthetic endocarditis at mid-term follow-up does not differ significantly from conventional prostheses. However, in this study, the incidence of stroke at 5 years (4%) is lower than that reported in other TAVR studies (10-15%). With respect to the need for permanent pacemaker implantation, an incidence of 7.9% was observed, which, although not very high, is still higher than that of conventional bioprostheses. Potential contributing risk factors include annular oversizing, intra-annular implantation, and preoperative findings such as right bundle branch block or prolonged QRS. Another advantage of this sutureless prosthesis was the reduction in ischemia and cardiopulmonary bypass times compared to conventional aortic valve prostheses. Although clinical benefits in shorter procedures, such as isolated AVR, are harder to demonstrate, greater benefits are likely to be found in combined surgeries involving multiple procedures. Additionally, the implant system design promotes the feasibility of minimally invasive approaches where conventional or stentless prostheses might present greater technical challenges. Meta-analyses comparing transcatheter bioprostheses with the Livanova® Perceval® have already shown a significant advantage of the latter at 5 years in terms of mortality and adverse events. However, these studies rely on observational data adjusted by propensity analysis, and there is a scarcity of studies evaluating TAVR beyond 5 years.

It is important to consider some limitations of this meta-analysis. First, five of the seven included studies were not randomized, which may introduce bias in the results. Additionally, unclear recruitment strategies were observed in some cases, and outcome definitions varied among studies. Furthermore, the sample size at mid-term follow-up was relatively small, potentially limiting the generalizability of the findings.

In this regard, our experience with the Livanova® Perceval® prosthesis at the University Hospital of A Coruña since 2013, with over 1,400 implants, provides a comprehensive view of the use of sutureless prostheses. We can affirm that our results largely align with previously published data. Noteworthy features and peculiarities include: 1) Significantly reduced ischemia and cardiopulmonary bypass times compared to conventional AVR. Notably, our figures are even lower than those mentioned in this review (32 min vs. 52 min in this study). 2) Larger-sized Livanova® Perceval® prostheses compared to conventional prostheses, resulting in lower peak and mean gradients in echocardiographic follow-ups (similar to those found in this review) that remain stable over time. 3) Earlier extubation and shorter ICU and hospital stays compared to conventional prostheses. 4) A lower incidence of atrioventricular blocks (AVB) currently below 4%, nearly half of that reported in this review. Although we initially had a higher AVB rate, since 2015, modifications in implantation technique and more precise prosthesis sizing, thus avoiding annular oversizing, have significantly reduced this complication. 5) Low incidence of structural deterioration and bioprosthetic dysfunction, following standardized definitions from the European consensus. With more than 7 years of clinical follow-up and an average echocardiographic follow-up of over 3 years, we found 0% severe structural deterioration, 8.8% moderate deterioration, and 2.9% bioprosthetic dysfunction, figures still lower than those in recent studies comparing conventional bioprostheses with TAVR, such as NOTION. 6) Feasible and effective “TAVI-in-Perceval” option thanks to the flexible nitinol stent of the Livanova® Perceval® prosthesis, which allows slight TAVR oversizing and has a “protective” effect to prevent coronary ostial obstruction through metal components that keep the Valsalva sinuses open. 7) Versatility of use in combined surgeries, not only coronary but also mitral surgery (series of over 50 patients with good outcomes). In summary, our more than 10 years of experience with this prosthesis support the results of this study in many aspects.

As TAVR has gained ground in recent years as the preferred option for patients over 75 years or those with high surgical risk, as cardiac surgeons, we must highlight AVR as an attractive, effective, durable, and safe option, especially in patients within a “gray zone” for therapeutic decision-making due to their clinical and anatomical characteristics. In this sense, the sutureless Livanova® Perceval® prosthesis stands out for its ease of implantation in diverse scenarios. The widely demonstrated short-term and now mid-term benefits discussed in this study (even surpassing TAVR in several aspects) further support the utility of the Livanova® Perceval® prosthesis in a wide variety of clinical and anatomical contexts, making it an increasingly relevant and growing alternative to conventional bioprosthetic AVR and TAVR.

REFERENCE:

Jolliffe J, Moten S, Tripathy A, Skillington P, Tatoulis J, Muneretto C, et al. Perceval valve intermediate outcomes: a systematic review and meta-analysis at 5-year follow-up. J Cardiothorac Surg. 2023 Apr 11;18(1):129. doi: 10.1186/s13019-023-02273-7.

González Barbeito M, Estévez-Cid F, Pardo Martínez P, Velasco García de Sierra C, Iglesias Gil C, Quiñones Laguillo C, et al. Surgical technique modifies the postoperative atrioventricular block rate in sutureless prostheses. J Thorac Dis. 2019 Jul;11(7):2945-295.  doi: 10.21037/jtd.2019.07.27.