Self-Expanding Transcatheter Aortic Valve System for Symptomatic High-Risk Patients With Severe Aortic Stenosis

A European update on transcatheter aortic valve implantation (TAVI) in the COVID era

Minimally invasive approaches for aortic valve replacement are now at the forefront of pathological aortic valve treatment. New trials show comparability of these devices to existing therapies, not only in high-risk surgical cohorts but also in low-risk and intermediate-risk cohorts. This review provides vital clinical and anatomical background to aortic valvular disease treatment guidelines, while also providing an update on transcatheter aortic valve implantation (TAVI) devices in Europe, their interventional trials and associated complications.

Modeling Tunable Fracture in Hydrogel Shell Structures for Biomedical Applications

Hydrogels are nowadays widely used in various biomedical applications, and show great potential for the making of devices such as biosensors, drug- delivery vectors, carriers, or matrices for cell cultures in tissue engineering, etc. In these applications, due to the irregular complex surface of the human body or its organs/structures, the devices are often designed with a small thickness, and are required to be flexible when attached to biological surfaces. The devices will deform as driven by human motion and under external loading. In terms of mechanical modeling, most of these devices can be abstracted as shells. In this paper, we propose a mixed graph-finite element method (FEM) phase field approach to model the fracture of curved shells composed of hydrogels, for biomedical applications. We present herein examples for the fracture of a wearable biosensor, a membrane-coated drug, and a matrix for a cell culture, each made of a hydrogel. Used in combination with experimental material testing, our method opens a new pathway to the efficient modeling of fracture in biomedical devices with surfaces of arbitrary curvature, helping in the design of devices with tunable fracture properties.

Transcatheter aortic valve implantation versus surgical aortic valve replacement in low-risk patients: a propensity score-matched analysis

OBJECTIVES

The aim of the study was to determine the differences in outcomes of surgical aortic valve replacement (SAVR) and transcatheter aortic valve implantation (TAVI) in low-risk patients.

METHODS

All patients with a logistic EuroSCORE II <4% who underwent transfemoral TAVI between 2008 and 2016 (n = 955) or SAVR between 2009 and 2014 (n = 886) at our centre were included. One hundred and nine patients per group were available for propensity score matching.

RESULTS

Mortality during the 30-day follow-up showed no differences (SAVR vs TAVI: 1.1% vs 1.8%, P = 1.0) but the rates of permanent pacemaker implantation (0.0 vs 14.8%, P < 0.001) and paravalvular leakage ≥ moderate (0.0 vs 7.0%, P = 0.017) were higher in TAVI patients. No difference was found regarding postoperative effective orifice area and transvalvular pressure gradients. Although, the 1-year survival was similar between both groups; 3- and 5-year survival was significantly inferior in the TAVI patient cohort.

CONCLUSIONS

TAVI yielded similar short-term outcomes compared with SAVR despite higher rates of permanent pacemaker implantation and paravalvular leakage ≥ moderate, but inferior long-term survival. Poorer long-term outcomes of the TAVI patient cohort were attributable to a more comorbid TAVI population. This emphasizes the need for long-term results from randomized controlled trials before TAVI can be broadly expanded to younger low-risk patients.

Comparison of latest generation supra-annular and intra-annular self-expanding transcatheter heart valves

Background

This study compares two latest-generation self-expanding transcatheter heart valves (THV), the supra-annular ACURATE neo (Boston Scientific) and the intra-annular Centera THV (Edwards Lifesciences).

Methods

In this single center observational cohort trial 317 patients treated with the ACURATE neo and 78 patients treated with the Centera TVH were included. The main endpoints were device success and the early safety endpoint at 30 days.

Results

Besides higher incidence of diabetes mellitus and higher body mass index in patients treated with the ACURATE neo THV, there were no baseline differences between the groups. Device success was similar in both groups (neo: 91.8% vs. Centera: 93.6%; P=0.598), with numerically higher rates of moderate to severe paravalvular leakage in the ACURATE neo group (4.7% vs. 1.3%; P=0.214). At 30 days all-cause mortality rates were low in both groups (0.3% vs. 0%; P=0.620) and no difference occurred in the early safety at 30 days (19.3% vs. 16.7%; P=0.599). However, all-cause stroke rates were significantly higher in patients treated with the Centera THV (6.4 vs. 1.6%; P=0.015).

Conclusions

The ACURATE neo and the Centera THV show low mortality rates as well as comparable, favorable hemodynamics. The finding of higher stroke rates at 30 days with the repositionable Centera SE-THV needs further assessment.

Novel Perspective for Antithrombotic Therapy in TAVI

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While surgical aortic valve replacement (SAVR) was for years the only available treatment for symptomatic aortic stenosis, the introduction of transcatheter aortic valve implantation (TAVI) in 2002 and the improvement of its technical aspects in the following years, has holistically changed the synchronous therapeutic approach of aortic valve stenosis. Recent evidence has expanded the indication of TAVI from high to lower surgical risk populations with symptomatic aortic stenosis. The administration of antithrombotic therapy periprocedurally and its maintenance after a successful TAVI is crucial for the prevention of complications and affects postprocedural survival. Randomized controlled trials investigating the appropriate combination and the duration of antithrombotic treatment after TAVI are for the moment scarce. This review article sheds light on the underlying pathogenetic mechanisms contributing in periprocedural TAVI thrombotic complications and discuss the efficacy of current antithrombotic policies as evaluated in randomized trials.

Transapical mitral valve-in-ring procedure with a novel self-expandable transcatheter heart valve: first- and last-in-man report

Interventional therapy of failing surgical mitral valve replacement and repair is an appealing option in patients who are not eligible for redo surgery. We herein report on the first-in-human use of a repositionable, self-expandable transcatheter heart valve with motorized delivery for a transapical mitral valve-in-ring procedure. After implantation, fluoroscopy showed no residual regurgitation and pressure measurements did not reveal any signs of left ventricular outflow tract obstruction.

1-Year Outcomes of the CENTERA-EU Trial Assessing a Novel Self-Expanding Transcatheter Heart Valve

OBJECTIVES

The purpose of this study is to report the 1-year results of the CENTERA-EU trial.

BACKGROUND

The CENTERA transcatheter heart valve (THV) (Edwards Lifesciences, Irvine, California) is a low-profile (14-F eSheath compatible), self-expanding nitinol valve, with a motorized delivery system allowing for repositionability. The 30-day results of the CENTERA-EU trial demonstrated the short-term safety and effectiveness of the valve.

METHODS

Implantations were completed in 23 centers in Europe, Australia, and New Zealand. Transfemoral access was used in all patients. Echocardiographic outcomes were adjudicated by a core laboratory at baseline, discharge, 30 days, 6 months, and 1 year. Major adverse clinical events were adjudicated by an independent clinical events committee.

RESULTS

Between March 2015 and July 2016, 203 high-risk patients (age 82.7 ± 5.5 years, 67.5% women, 68.0% New York Heart Association functional class III or IV, Society of Thoracic Surgeons score 6.1 ± 4.2%) with severe, symptomatic aortic stenosis underwent transcatheter aortic valve replacement with the CENTERA THV. The primary endpoint of the study was 30-day mortality (1.0%). At 1 year, overall mortality was 9.1%, cardiovascular mortality was 4.6%, disabling stroke was 4.1%, new permanent pacemakers were implanted in 6.5% of patients at risk, and cardiac-related rehospitalization was 6.8%. Hemodynamic parameters were stable at 1 year, with a mean aortic valve gradient of 8.1 ± 4.7 mm Hg, a mean effective orifice area of 1.7 ± 0.42 cm², and no incidences of severe or moderate aortic regurgitation.

CONCLUSIONS

The CENTERA-EU trial demonstrated mid-term safety and effectiveness of the CENTERA THV, with low mortality, sustained improvements in hemodynamic performances, and low incidence of permanent pacemaker implantations in high-risk patients with symptomatic aortic stenosis. (Safety and Performance of the Edwards CENTERA-EU Self-Expanding Transcatheter Heart Valve [CENTERA-2]; NCT02458560).

Current issues in transcatheter aortic valve replacement

Aortic stenosis is the most common valvular disease worldwide. With transcatheter aortic valve replacement (TAVR) being increasingly expanded to lower-risk populations, several challenging issues remain to be solved. The present review aims at discussing modern approaches to such issues as well as the current status of TAVR. TAVR has undergone several developments in the recent years: an increased use of transfemoral access, the development of prostheses in order to adapt to challenging anatomies, improved delivery systems with repositioning features, and outer skirts aiming at reducing paravalvular leak. The indication of TAVR is increasingly being expanded to patients with lower surgical risk. The main clinical trials supporting such expansion are reviewed and the latest data on low-risk patients are discussed. A number of challenges need still to be addressed and are also reviewed in this paper: the need for updated international guidelines including the latest evidence; a reduction of main complications such as permanent pacemaker implantation, paravalvular leak, and stroke (and its potential prevention by using anti-embolic protection devices); the appropriate role of TAVR in patients with concomitant cardiac ischemic disease; and durability of bio-prosthetic implanted valves. Finally, the future perspectives for TAVR use and next device developments are discussed.

Impact of Sapien 3 Balloon-Expandable Versus Evolut R Self-Expandable Transcatheter Aortic Valve Implantation in Patients With Aortic Stenosis

Background:

Two competing transcatheter aortic valve replacement (TAVR) technologies are currently available. Head-to-head comparisons of the relative performances of these 2 devices have been published. However, long-term clinical outcome evaluation remains limited by the number of patients analyzed, in particular, for recent-generation devices.

Methods:

Based on the French administrative hospital-discharge database, the study collected information for all consecutive patients treated with a TAVR device commercialized in France between 2014 and 2018. Propensity score matching was used for the analysis of outcomes during follow-up. The objective of this study was to analyze the outcomes of TAVR according to Sapien 3 balloon-expandable (BE) versus Evolut R self-expanding TAVR technology at a nationwide level in France.

Results:

A total of 31 113 patients treated with either Sapien 3 BE or Evolut R self-expanding TAVR were found in the database. After matching on baseline characteristics, 20 918 patients were analyzed (10 459 in each group with BE or self-expanding valves). During follow-up (mean [SD], 358 [384]; median [interquartile range], 232 [10–599] days), BE TAVR was associated with a lower yearly incidence of all-cause death (relative risk, 0.88; corrected P =0.005), cardiovascular death (relative risk, 0.82; corrected P =0.002), and rehospitalization for heart failure (relative risk, 0.84; corrected P <0.0001). BE TAVR was also associated with lower rates of pacemaker implantation after the procedure (relative risk, 0.72; corrected P <0.0001).

Conclusions:

On the basis of the largest cohort available, we observed that Sapien 3 BE valves were associated with lower rates of all-cause death, cardiovascular death, rehospitalization for heart failure, and pacemaker implantation after a TAVR procedure.

Safety and Performance Outcomes of a Self-Expanding Transcatheter Aortic Heart Valve: The BIOVALVE Trials

OBJECTIVES

The aim of this study was to assess the safety and performance of a newly introduced transfemoral self-expanding supra-annular transcatheter heart valve.

BACKGROUND

Transcatheter aortic valve replacement has become an established procedure, and newer transcatheter heart valves aim to supplement the current armamentarium.

METHODS

BIOVALVE-I is a prospective, single-center feasibility study enrolling 13 high-risk patients with severe aortic stenosis, and BIOVALVE-II is a multicenter pilot study enrolling a further 55 patients under the same protocol.

RESULTS

Patients' mean age was 82.4 ± 5.3 years, 57.4% had concomitant coronary artery disease, 50.0% had renal insufficiency stage ≥3, 32.4% had diabetes mellitus, 29.4% had current anemia, 19.1% had chronic obstructive pulmonary disease, 19.1% were frail, and 17.6% had prior cerebrovascular events. The primary endpoint, early safety according to the Valve Academic Research Consortium-2 guidelines, was observed in 13 patients (19.1%). One patient (1.5%) died through 30 days of a noncardiac cause, and 4 patients (7.8%) died through 180 days. Disabling stroke occurred at 30 days in 1 patient (1.5%) and at 180 days in 2 patients (3.2%). New permanent pacemakers up to 30 days were implanted in 9 patients (13.4%). Two patients (3.8%) had moderate or severe paravalvular leakage at 30 days and 4 (9.1%) at 6 months, mean effective orifice area was 2.0 ± 0.4 cm² and 1.9 ± 0.5 cm², and mean gradient was 6.4 mm Hg at 30 days and 6 months.

CONCLUSIONS

Clinical outcomes with the Biovalve self-expanding transcatheter heart valve were similar to those seen in other first-in-human studies with first-generation devices for severe aortic stenosis.

Transcatheter aortic valve replacement: clinical safety and performance data

Introduction: Patients with severe aortic stenosis and regurgitation who are inoperable or at high-risk for surgery can be treated with transcatheter aortic valve replacement (TAVR). The aim of this study was to provide a comprehensive overview of the literature of TAVR and reported clinical and performance outcomes. Areas covered: A total of 16 devices, described in 204 articles describing clinical and performance outcomes, were included. The most frequently observed outcome was 30-day mortality, ranging between 0-23%. Other commonly reported clinical outcomes were 30-day stroke, ranging between 0-14.3% and pacemaker implantation, ranging from 0-44.9%. The most common valve performance outcome was aortic valve regurgitation, however, mostly reported at 7 days follow-up. Next to a follow-up period of 30 days, numerous articles reported outcomes at 6 months and 1 year. The numbers of articles describing outcomes with a longer follow-up as well as including intermediate and low-risk patients were limited. Expert commentary: This literature review provided a clear overview of the reported clinical and performance outcomes of TAVR devices. Despite the frequently used VARC-2 definitions, we identified a huge variation across studies. Future studies using standardized definitions of study set-ups and outcomes are essential and might lead to better insights of TAVR.

Advances in Clinical Cardiology 2018: A Summary of Key Clinical Trials

INTRODUCTION

Many important clinical trials in cardiology were published or presented at major international meetings throughout 2018. This paper aims to offer a concise overview of these significant advances and to put them into clinical context.

METHODS

Trials presented at the major international cardiology meetings during 2018 were reviewed including The American College of Cardiology, EuroPCR, The European Society of Cardiology, PCR London Valves, Transcatheter Cardiovascular Therapeutics, and the American Heart Association. In addition to this a literature search identified several other publications eligible for inclusion based on their relevance to clinical cardiology, their potential impact on clinical practice and on future guidelines.

RESULTS

A total of 78 trials met the inclusion criteria. New interventional and structural data include trials examining novel stent designs (Biofreedom™, COMBO), use of drug-coated balloons in patients with high bleeding risk, intervention in stable coronary artery disease, revascularisation strategy in ST elevation myocardial infarction, transcatheter aortic valve replacement in low-risk patients, and percutaneous mitral or tricuspid valve interventions. Preventative cardiology data included the use of sodium glucose cotransporter-2 inhibitors (empagliflozin, dapagliflozin, canagliflozin), proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitors (alirocumab) and approaches of hypertension management. Antiplatelet data included trials evaluating both the optimal length of course and combination of antiplatelet agents. Heart failure data included trials of sacubitril-valsartan during acute hospital admission and the management of chemotherapy-induced cardiotoxicity. Electrophysiology data included trials examining atrial fibrillation ablation, wearable cardiac defibrillators (LifeVest) and His-bundle pacing.

CONCLUSION

This article presents key clinical trials completed during 2018 and should be valuable to both cardiology clinicians and researchers.

The evolution of device technology in transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) has rapidly evolved and changed the landscape of structural interventional cardiology. Advances in transcatheter heart valve (THV) prostheses and TAVI-enabling devices have simplified the procedure, reduced the risk of complications, improved short- and long-term outcomes and broadened the applications of TAVI, not only in challenging patients and complex anatomies but also in intermediate-risk or even in low-risk patients, where surgical valve replacement constitutes an effective and well-established therapy. In this review article, we provide an overview of the developments in TAVI devices which have played a vital role in TAVI evolution: we describe the prostheses that failed to reach clinical practice, we present the characteristics of the first valves that were tested in the clinical arena, we summarise the evidence from the first studies that highlighted the potential but also the limitations of TAVI, and we present the advanced next-generation THV prostheses that have an improved performance and safety profile.

Self-expanding CENTERA valve for the treatment of severe, symptomatic aortic stenosis

Transcatheter aortic valve implantation (TAVI) is now an established treatment option for both high and intermediate operative risk patients with severe symptomatic aortic stenosis. The number of patients undergoing TAVI has increased over the last decade warranting continued technological improvements in transcatheter heart valve (THV) systems. The novel CENTERA self-expanding THV (Edwards Lifesciences, CA, USA) received CE approval this year. It is deliverable through a 14Fr sheath and has a unique motorized delivery system. The CENTERA-2 study results demonstrated a favorable survival rate at 30 days (99%), as well as a low need for new permanent pacemaker implantation (4.9%). 1-year outcomes reported a low incidence of >moderate paravalvular leak (0.6%) and consistently favorable THV hemodynamics making this a competitive THV for patients with severe aortic stenosis.

Innovations in Transcatheter Valve Technology: What the Next Five Years Hold

Transcatheter aortic valve replacement is indicated for the treatment of symptomatic severe aortic stenosis in patients at intermediate or greater risk for surgery. Future indications may include low-risk patients, asymptomatic patients, bicuspid valves, moderate aortic stenosis, and pure native aortic valve regurgitation. Key hurdles to overcome include pacemaker risk, vascular injury, paravalvular regurgitation, coronary artery reaccess, durability, and embolic risk. New valve designs include synthetic polymeric valves that may allow for greater durability, in addition to advances in terms of precise positioning and repositioning to reduce the complication rate.

Transcatheter aortic valve replacement: The year in review 2017

This article is a continuation of our previously published annual reviews of transcatheter aortic valve replacement (TAVR). In 2017, TAVR further established a foothold in the management of intermediate risk patients with the publication of SURTAVI trial. Randomized trials also addressed the use of cerebral protection during TAVR and single versus dual antiplatelet therapy after TAVR. Newer generation valve systems continued to be studied for their efficacy and safety. This paper summarizes the major studies published in 2017.

Computed tomography-based oversizing and incidence of paravalvular aortic regurgitation and permanent pacemaker implantation with a new-generation self-expanding transcatheter heart valve

AIMS

We aimed to evaluate the relationship between CT-based annular perimeter oversizing and the incidence of paravalvular aortic regurgitation (PAR) and permanent pacemaker (PPM) implantation in patients treated with the new self-expanding CENTERA transcatheter heart valve (THV) for severe aortic stenosis.

METHODS AND RESULTS

One hundred and ninety-eight patients in the CENTERA-EU trial were stratified a priori into four groups based on the perimeter oversizing (2.5-10%, 10-15%, 15-20% and >20%). PAR at 30 days was moderate or higher in 0.6% of patients. The frequency of PPM implantation was 4.9%. The mean perimeter oversizing was 16.2±5.6%. For patients with a perimeter oversizing >10%, an inverse relationship between oversizing and ≥mild PAR was observed (43.3% for 10-15% oversizing; 37.7%, 15-20%; 33.3%, >20%). No association between oversizing and effective orifice area was observed. The optimal cut-off value of perimeter oversizing for the prediction of ≥mild PAR was 15.9% (AUC 0.718, 95% CI: 0.576, 0.860). No annular ruptures were observed.

CONCLUSIONS

The CENTERA THV appears to have a wide range of sizing tolerance. The degree of oversizing to mitigate PAR is relatively low compared to other self-expanding transcatheter devices. There appears to be no compromise between occurrence of PAR and PPM across this wide range of oversizing.

TAVI and Post Procedural Cardiac Conduction Abnormalities

Transcatheter aortic valve implantation (TAVI) is a worldwide accepted alternative for treating patients at intermediate or high risk for surgery. In recent years, the rate of complications has markedly decreased except for new-onset atrioventricular and intraventricular conduction block that remains the most common complication after TAVI. Although procedural, clinical, and electrocardiographic predisposing factors have been identified as predictors of conduction disturbances, new strategies are needed to avoid such complications, particularly in the current TAVI era that is moving quickly toward the percutaneous treatment of low-risk patients. In this article, we will review the incidence, predictive factors, and clinical implications of conduction disturbances after TAVI.