Use of a Repositionable and Fully Retrievable Aortic Valve in Routine Clinical Practice

Increased cardiovascular mortality in patients with mechanically expandable transcatheter aortic valve and without permanent pacemaker

INTRODUCTION

Use of the mechanically expandable transcatheter aortic valve (MEV) has been recently linked to increased risks of valve dysfunction and cardiovascular mortality. The risk of developing conduction disturbance with the MEV valve is well known, and the negative prognostic impact of permanent pacemaker implantation (PPI) after transcatheter aortic valve implantation is another consideration.

AIM

This study aimed to compare the mid-term survival of patients with MEV and self-expandable valves (SEV), and to examine survival of both groups according to the presence or absence of PPI.

METHODS

This single-centre, retrospective, observational study examined data from MEV and SEV groups comprising 92 and 373 patients, respectively. The mean clinical follow-up was 2.5±1.7 years. Mortality information was obtained from the National Institutes of Health Information and Statistics.

RESULTS

Baseline characteristics were comparable between the groups. The log-rank test showed higher cardiovascular mortality in the MEV group (p=0.042; the relative risk (RR) 1.594 (95% CI 1.013 to 2.508)). The Cox proportional hazards model identified MEV implantation as an independent predictor of cardiovascular mortality. The rate of PPI was twice as high in the MEV vs SEV group (33.7% vs 16.1%; p<0.001). We compared the survival of both groups according to the presence or absence of PPI and found higher mortality in the MEV group without PPI versus the SEV group without PPI (p=0.007; RR 2.156 (95% CI 1.213 to 3.831)). Survival did not differ in the groups with PPI.

CONCLUSIONS

A higher mid-term cardiovascular mortality rate was observed with MEV versus SEV implants. Comparing both groups according to the presence or absence of PPI, we observed a higher mortality risk in patients with MEV without PPI than in SEV without PPI. In contrast, mortality did not differ between the groups when PPI was implanted.

Prosthesis Tailoring for Patients Undergoing Transcatheter Aortic Valve Implantation

Transcatheter aortic valve implantation (TAVI) has risen over the past 20 years as a safe and effective alternative to surgical aortic valve replacement for treatment of severe aortic stenosis, and is now a well-established and recommended treatment option in suitable patients irrespective of predicted risk of mortality after surgery. Studies of numerous devices, either newly developed or reiterations of previous prostheses, have been accruing. We hereby review TAVI devices, with a focus on commercially available options, and aim to present a guide for prosthesis tailoring according to patient-related anatomical and clinical factors that may favor particular designs.

Innovative Approach to Manage Transcatheter Aortic Valve Embolization

We describe the case of a patient with an ascending aortic aneurysm who underwent valve-in-valve transcatheter aortic valve implantation, which was complicated by valve embolization. After a multidisciplinary discussion and an innovative approach, the free-floating embolized valve was anchored securely in the aortic arch with an uncovered aortic endovascular stent. (Level of Difficulty: Intermediate.).

Mid-term outcomes of patients with Lotus and Evolut transcatheter valves

Introduction

Long-term data on the Lotus^® (Boston Scientific, USA) valve are lacking.

Aim

To evaluate mid-term outcomes of aortic stenosis patients treated with either Lotus or Evolut R^® valves (Medtronic, USA).

Material and methods

Our study sample comprised 190 patients (71 Lotus and 119 Evolut valves). The mean clinical follow-up was 2.0 ±0.9 years. Information on mortality was obtained from the National Institutes of Health Information and Statistics.

Results

No significant differences existed in baseline characteristics between the groups. The rate of procedural complications was low and without significant differences between groups. The log rank test showed higher mortality in the Lotus group for cardiovascular mortality (p = 0.02; RR = 2.4, 95% CI: 1.123–5.075). Multivariable analysis revealed that the Lotus valve was independently associated with cardiovascular mortality (p = 0.03). At the end of echocardiography follow-up (4.1 ±0.9 years), we found a significantly higher mean aortic valve gradient (AVGm) in the Lotus group than in the Evolut group (17.9 ±9.5 vs. 10.2 ±3.5 mm Hg; p = 0.0006), and 3 (10%) patients from the Lotus group suffered from symptomatic re-stenosis requiering re-intervention.

Conclusions

The results of our study suggest that higher cardiovascular mortality rates during mid-term follow-up were associated with Lotus compared with Evolut valves. Higher AVGm in the Lotus valves suggests the possibility of accelerated prosthesis degeneration.

The ACURATE neo™ and neo2™ Valve Systems

Based on the strength of data from randomized trials and real-world clinical studies, transcatheter aortic valve replacement (TAVR) has become a popular and effective alternative to surgical valve replacement in patients with symptomatic aortic stenosis. The ACURATE neo™ (Boston Scientific, Marlborough, MA, USA) valve system has been commercially available for transfemoral TAVR in Europe since 2014. ACURATE neo2™ is an evolution of the neo design and was declared CE marked by the manufacturer in 2020. The neo and neo2 valves have been studied in high-risk patients, and the currently active randomized trial for neo2 will include over 1,500 patients of all risk categories in the USA. The goal of this review is to help inform the TAVR community about the ACURATE valve.

The Allegra transcatheter heart valve: Short term results from a multicenter registry

OBJECTIVES

We aimed to determine the safety and efficacy of the Allegra transcatheter heart valve (THV) for the treatment of severe aortic valve stenosis in a large patient population treated under real-world conditions.

BACKGROUND

The Allegra is a novel self-expanding THV with supra-annular bovine leaflets. The valve is available in three different sizes (23, 27, and 31 mm), all are delivered through an 18F sheath.

METHODS

Consecutive patients undergoing TAVR with the Allegra THV were enrolled in a multicenter-registry. Data were collected throughout initial hospital-stay and at 30-day follow-up. Clinical endpoints were defined according to the updated definitions of the Valve-Academic-Research-Consortium.

RESULTS

This registry included 255 patients (mean age 83 ± 6 years, 48% women) from four European centers. Median European System for Cardiac Operative Risk Evaluation II score (EuroSCORE II) was 3.3% (IQR 1.9-5.8%). Acute device success was 95.7%. The remaining 11 patients had either moderate paravalvular regurgitation immediately after the procedure (7 patients) or the device could not be optimal positioned requiring implantation of a second THV (4 patients). Major vascular complications and major/life-threatening bleedings occurred in 10 (3.9%) and 12 (4.7%) patients, respectively. At 30 day follow-up, mean effective orifice area was 2.2 ± 0.5 cm² , mean gradient was 6.9 ± 3.8 mmHg, 7 (3.3%) patients had more than mild paravalvular leakage, 3 patients (1.2%) had died, 6 patients (2.4%) had a stroke and 30 (12.8%) patients had required implantation of a new permanent pacemaker.

CONCLUSIONS

Transfemoral implantation of the Allegra THV resulted in favorable clinical and echocardiographic outcomes during hospitalization and short-term follow up.

Impact of Interventricular membranous septum length on pacemaker need with different Transcatheter aortic valve implantation systems

Background The need for new permanent pacemaker implantation (PPI) after Transcatheter Aortic Valve Implantation (TAVI) remains a critical issue. Membranous Septum (MS) length is associated with PPI after TAVI. The aim of this study was to identify different MS thresholds for the contemporary THV-platforms. Methods This retrospective, case-control study enrolled all patients who underwent a successful TAVI procedure with contemporary THV-platforms in the Erasmus University Medical Center between January 2016 and March 2020. The follow-up period for new PPI was 30 days. MS-length was determined by Computed Tomography. Results The study consisted 653 TAVI patients with median age 80.6 years (IQR 74.7-84.8). New PPI occurred in 120 patients (18.4%). Patients with new PPI had a shorter MS-length (2.9 mm (IQR 2.3-4.3) vs. 4.2 mm (IQR 2.9-5.7), p < 0.001). MS-length < 3 mm identified a high-risk phenotype with 30.3% PPI-rate (OR 6.5 [95%CI 2.9-14.9]), MS-length 3-6 mm an intermediate-risk phenotype with 15.4% PPI-rate (OR 2.7 [95%CI 1.2-6.2]) and MS > 6 mm a low-risk phenotype with a 6.3% PPI-rate (reference). For the Lotus valve, there was no significant difference in PPI-rates between the high-risk (45.8%, OR 3.5 [95%CI 0.8-15.1]) and low-risk group (20%). By multivariate analysis MS-length, Agatston-score, use of Lotus valve, and ECG with first-degree AV block, RBBB or bifascular block were independent predictors for new PPI. Conclusion MS-length was an independent predictor for new PPI post-TAVI. Three phenotypes were found based on MS-length. MS < 3 mm was universally associated with a high risk for new PPI (>30%). MS > 6 mm represented a low-risk phenotype with PPI-rate < 10%. PPI-rate varied per THV type in the intermediate phenotype. PPI-rate with Lotus was high regardless of MS-length.

Evaluation of procedural and clinical outcomes of transcatheter aortic valve implantation: A single-center experience

Objective:

Transcatheter aortic valve implantation (TAVI) is an established alternative to surgical aortic valve replacement. Our study aimed to evaluate the implementation of TAVI at our large-volume center, having an all-comer patient population with short and long-term follow-ups.

Methods:

This retrospective, single-center analysis included 556 consecutive patients with symptomatic severe aortic stenosis (AS) who underwent TAVI between July 2011 and December 2019.

Results:

The mean age of the entire population was 77.6±7.9 years, and 54.9% were women. The Society of Thoracic Surgeons (STS) mean score of the cohort was 6.0%±3.5%. The balloon-expandable valve (Sapien XT, Sapien 3; Edwards Lifesciences, Irvine, California) was the most frequently used valves in this cohort (94.6%). Transfemoral access was used in 96.3% of patients. Implantation success was achieved in 96.6% of cases. During the TAVI procedure, 7.2% of patients required permanent pacemaker implantation, with 37.5% in the Lotus valve group needing the most permanent pacemakers. The mean length of hospital stay for the entire cohort was 4.5±2.3 days. Overall, 22 (3.9%) in-hospital deaths occurred before hospital discharge. The mean follow-up period was 15.1±14.9 months for all patients, and a significant improvement was noted in all echocardiographic parameters and functional capacity. Paravalvular leak (PVL) was documented in 18.9% patients, mild in 17.9%, and moderate in 1% at discharge. No cases with severe PVL, necessitating additional procedures. The multiple logistic regression analysis revealed that sex, STS score, baseline SYNTAX score, bicuspid valve morphology, common femoral artery diameter, and post-TAVI PVL were independent predictors of overall mortality.

Conclusion:

To our knowledge, this study, which is the largest single-center real-world experience of TAVI in Turkey, demonstrated low complication rates with favorable short- and mid-term THV performance in patients undergoing TAVI.

The incidence and impact of cardiac conduction disturbances after transcatheter aortic valve replacement

Transcatheter aortic valve replacement (TAVR) has developed into an established therapy for patients with severe aortic stenosis (AS) across the spectrum of surgical risk. Despite improvements in transcatheter heart valve (THV) technologies and procedural techniques, cardiac conduction disturbances, including high degree atrioventricular block (AVB) requiring permanent pacemaker (PPM) implantation and new-onset left bundle branch block (LBBB), remain frequent complications. TAVR-related conduction disturbances occur due to injury to the conduction system from interactions with interventional equipment and the transcatheter valve stent frame. Risk factors for post-TAVR conduction disturbances have been identified and include clinical characteristics, baseline electrocardiogram findings (right bundle branch block), anatomic factors, and potentially modifiable procedural factors (type of transcatheter valve, depth of implantation, over-sizing). New-onset LBBB and PPM implantation after TAVR have been shown to be associated with adverse long-term clinical outcomes, including mortality and heart failure hospitalization. These clinical consequences are likely to be of increasing importance as TAVR is utilized in younger and lower risk population. This review provides an updated overview of the literature regarding the incidence, predictors, and clinical outcomes of TAVR-related conduction disturbances, as well as proposed strategies for the management of this frequent clinical challenge.

Transcatheter aortic valve replacement: potential use in lower-risk aortic stenosis

INTRODUCTION

The widespread use of transcatheter aortic valve implantation (TAVI) is expanding to low-risk patients. Nevertheless, a low clinical risk does not always correspond to a low procedural risk for the percutaneous approach.

AREAS COVERED

The initial trials on TAVI in low-risk populations had encouraging results, showing non-inferiority in comparison to surgical aortic valve replacement (SAVR). However, the low-risk definition is based on risk score calculators developed for the surgical setting and not including other specific features that are more relevant to TAVI and can affect procedural outcomes. For example, the presence of bicuspid aortic valves, high calcific burden, low coronary height or conduction disturbances is all potentially associated with suboptimal results or even procedural complications. In addition, the lack of longer follow-up prevents us to draw conclusions about long-term outcomes, including data about valve durability and coronary re-access.

EXPERT OPINION

Although current evidence suggest similar results for TAVI and SAVR in low-risk populations, there are some technical and procedural limitations that still need to be addressed in order to close the gap between TAVI and surgery. Optimal, lasting results with a low rate of procedural complications are highly expected in low-risk, otherwise healthy subjects, with potential for longevity.

Considerations for Optimal Device Selection in Transcatheter Aortic Valve Replacement: A Review

Importance

Aortic valve stenosis (AS) is the most common manifestation of acquired valvular heart disease in developed countries. Several large-scale randomized clinical trials investigating the entire spectrum of patients with severe symptomatic AS from low to prohibitive risk have established transcatheter aortic valve replacement (TAVR) as a safe and effective alternative to surgical aortic valve replacement.

Observations

There are currently only 3 types of TAVR devices commercially available in the US, but several other valve types are undergoing clinical trials in the US. Because of fundamental differences in engineering features, each TAVR device type has specific strengths and limitations. This review aims to provide an overview of design features and clinical outcomes of various TAVR devices that are either commercially available or undergoing clinical investigation.

Conclusions and Relevance

Given the lack of large-scale head-to-head comparisons of various TAVR devices and the rapid development of new device iterations, there is insufficient evidence to claim superiority of one device type over another. Nonetheless, as each TAVR device has unique design characteristics, certain patient-related and anatomy-related factors may slightly favor one or several particular designs.

Insights on Embolic Protection, Repositioning, and Stroke: A Subanalysis of the RESPOND Study

RESPOND is a prospective, single-arm study enrolling 1014 transcatheter aortic valve replacement (TAVR) patients. The objective of this analysis is to assess the impact of cerebral embolic protection (CEP) devices and prosthetic valve repositioning on the risk of neurologic complications in patients treated with the fully repositionable Lotus Valve in the RESPOND postmarket study. Valve repositioning and CEP use were at the operators' discretion. Stroke events were adjudicated by an independent medical reviewer. This analysis assessed the baseline differences among patients according to CEP use and valve repositioning and evaluated the neurological complications at 72 hours after TAVR, hospital discharge, and 30-day follow-up. A multivariate analysis was performed to identify the potential predictors of stroke. Of the 996 patients implanted with the Lotus Valve (mean age: 80.8 years, 50.8% female, STS score 6.0 ± 6.9), 92 cases (9.2%) used CEP. The overall rate of acute stroke/transient ischemic attack (TIA) was 3.0% at 72 hours after TAVR. The 72-hour stroke/TIA rate was 1.1% in patients who had CEP and 3.2% in those who did not. Use of CEP was associated with a 2.1% absolute reduction in the risk of acute neurological events (relative risk reduction: 65.6%), although the difference was not statistically significant (p=0.51). Repositioning of the Lotus Valve occurred in 313/996 procedures (31.4%). The 72-hour rate of stroke/TIA was similar in patients who had valve repositioning (2.9%) compared with those who did not (3.1%; p=0.86). The selective use of a CEP device in the RESPOND study was associated with a nonsignificantly lower risk for stroke within 72 hours. The use of the repositioning feature of the Lotus Valve did not increase the stroke risk.

Update on Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR) is a minimally invasive approach to treat symptomatic severe aortic stenosis. The patient populations that have been shown to benefit from this procedure continue to grow with time. Techniques and technology in TAVR persistently advance with a continued trend toward improved outcomes for patients. In this review, we highlight the advances in vascular access, TAVR valve design, progress in reducing procedural complications, and emerging evidence in the field.

Transcatheter Aortic Valve Replacement with the Lotus Valve: Concept and Current State of the Data

Multiple transcatheter heart valve iterations have created an interesting range of options with which to perform transcatheter aortic valve replacement. The Lotus valve has several attractive features. The ability to eradicate even mild paravalvular leak mirrors the outcomes of surgical aortic valve replacement. New design iterations of the Lotus valve and refined sizing algorithms may help mitigate the need for permanent pacemaker implantation and consolidate its best-in-class results in terms of paravalvular leak. Ongoing trials should help define the safety and efficacy of the Lotus transcatheter heart valve in contemporary practice.