Transcatheter Versus Surgical Aortic Valve Replacement in Young, Low-Risk Patients With Severe Aortic Stenosis

An Updated Comprehensive Review of Existing Transcatheter Aortic Valve Replacement Access

For the past 20 years, transcatheter aortic valve replacement (TAVR) has been the treatment of choice for symptomatic aortic stenosis. The transfemoral (TF) access is considered the gold standard approach for TAVR. However, TF-TAVR cannot be performed in some patients; thus, alternative accesses are required. Our review paper generalises the TAVR accesses currently available, including the transapical, transaortic, trans-subclavian/axillary, transcarotid, transcaval, and suprasternal approaches. Their advantages and disadvantages have been analysed. Since there is no standard recommendation for an alternative approach, access selection depends on the expertise of the local cardiac team, patient characteristics, and access properties. Each TAVR centre is recommended to master a minimum of one non-TF access alternative. Of note, more evidence is required to delve into the clinical outcomes of each approach, at both early and long-term (Figure 1).

3-Year Outcomes From the Evolut Low Risk TAVR Bicuspid Study

BACKGROUND

Outcomes from transcatheter aortic valve replacement (TAVR) in low-surgical risk patients with bicuspid aortic stenosis beyond 2 years are limited.

OBJECTIVES

This study aimed to evaluate 3-year clinical and echocardiographic outcomes from the Evolut Low Risk Bicuspid Study.

METHODS

The Evolut Low Risk Bicuspid Study is a prospective, multicenter, single-arm study conducted in 25 U.S.

CENTERS

Patients with severe aortic stenosis at low surgical risk with bicuspid aortic valve anatomy (all subtypes) underwent TAVR with a self-expanding, supra-annular Evolut R or PRO (Medtronic) bioprosthesis. An independent clinical events committee adjudicated all deaths and endpoint-related adverse events, and a central echocardiographic core laboratory assessed hemodynamic endpoints.

RESULTS

An attempted implant was performed in 150 patients from December 2018 to October 2019. The mean age was 70.3 ± 5.5 years, 48% (72/150) of the patients were women, and the mean Society of Thoracic Surgeons Predicted Risk of Mortality score was 1.3% (Q1-Q3: 0.9%-1.7%). Sievers type 1 was the dominant bicuspid morphology (90.7%, 136/150). The Kaplan-Meier rates of all-cause mortality or disabling stroke were 1.3% (95% CI: 0.3%-5.3%) at 1 year, 3.4% (95% CI: 1.4%-8.1%) at 2 years, and 4.1% (95% CI: 1.6%-10.7%) at 3 years. The incidence of new permanent pacemaker implantation was 19.4% (95% CI: 12.4%-29.6%) at 3 years. There were no instances of moderate or severe paravalvular aortic regurgitation at 2 and 3 years after TAVR.

CONCLUSIONS

The 3-year results from the Evolut Low Risk Bicuspid Study demonstrate low rates of all-cause mortality or disabling stroke and favorable hemodynamic performance.

Impact of Elevated Gradients After Transcatheter Aortic Valve Implantation for Degenerated Surgical Aortic Valve Bioprostheses

BACKGROUND

Elevated aortic valve gradients are common after transcatheter aortic valve implantation for degenerated surgical aortic valve replacement bioprostheses, but their clinical impact is uncertain.

METHODS

A total of 12 122 patients who underwent transcatheter aortic valve implantation-in-surgical aortic valve replacement from November 2011 to December 2019 in the Society of Thoracic Surgery/American College of Cardiology Transvalvular Therapeutics Registry were included. The primary outcome was a composite of 1-year all-cause mortality, stroke, myocardial infarction, or valve reintervention. Secondary outcomes included 1-year all-cause mortality, readmission, and change from baseline 12-question self-administered Kansas City Cardiomyopathy Questionnaire-Overall Summary Score. Due to nonlinearity observed with restricted cubic splines analysis, a Cox regression analysis with aortic valve mean gradient modeled as a spline-continuous variable (with 20 mm Hg as a cutoff) was used to study the 1-year composite outcome and mortality.

RESULTS

The composite outcome occurred most frequently in patients with aortic valve mean gradient ≥30 and <10 mm Hg, as compared with those with 10 to 20 and 20 to 30 mm Hg ranges (unadjusted rates, 13.9%, 12.1%, 7.5%, and 6.5%, respectively; P=0.002). When the mean aortic valve gradient was ≥20 mm Hg, higher gradients were associated with greater risk of the 1-year composite outcome (adjusted hazard ratio, 1.02 [1.02-1.03] per mm Hg; P<0.001) and 1-year mortality (adjusted hazard ratio, 1.02 [1.00-1.03] per mm Hg; P=0.007). Whereas when the mean aortic valve gradient was <20 mm Hg, higher gradients were not significantly associated with the composite outcome (adjusted hazard ratio, 0.99 [0.98-1.003] per mm Hg; P=0.12) but were associated with lower 1-year mortality (adjusted hazard ratio, 0.98 [0.97-0.99] per mm Hg; P=0.007).

CONCLUSIONS

The relationship between postprocedural aortic valve mean gradient after transcatheter aortic valve implantation-in-surgical aortic valve replacement and clinical outcomes is complex and nonlinear, with relatively greater adverse events occurring at low and high gradient extremes. Further study of factors mediating the relationship between postprocedural gradients and clinical outcomes, including low-flow states, is necessary.

Visualization of transcatheter aortic valve implantation from the perspective of bibliometric analysis

Transcatheter aortic valve implantation (TAVI) was originally devised as a treatment for patients with aortic stenosis (AS). It has since emerged as a beneficial alternative to surgical aortic valve replacement (SAVR), extending its reach to a broader array of patients. Our objective was to illustrate the developmental trends and focus areas in TAVI research. We sourced a total of 11,480 research papers on TAVI, published between 1994 and 2022, from the Web of Science Core Collection (WoSCC) database. We conducted a bibliometric analysis of these publications, generating cooperation maps, performing co-citation analysis of journals and references, and carrying out a cluster analysis of keywords. Our findings indicate that TAVI research grapples with numerous clinical challenges. We created knowledge maps that highlight contributing countries/institutions, authors, journals with high publication and citation rates, and notable references in this domain. North America and Europe have been at the forefront of research within the TAVI field. The institutions and authors from these regions exert significant influence in this area of study. Beginning in 2009, China has progressively expanded its research on TAVI over the past two decades. We anticipate that future research will increasingly focus on three key areas: implementation scope, lifelong management, outcomes and predicting the risk of TAVI. Research on TAVI is flourishing. Cooperation among different countries and institutions in this field must be strengthened in the future, especially for developing counties.

Twenty-year experience following aortic valve replacement in patients younger than 60 years of age

OBJECTIVE

Reports on long-term outcomes of surgical aortic valve replacement (AVR) for patients aged < 60 years are scarce in Japan. Hence, we aimed to evaluate these outcomes in patients aged < 60 years.

METHODS

Between March 2000 and December 2020, 1477 patients underwent aortic valve replacement. In total, 170 patients aged < 60 years who underwent aortic valve replacement were recruited. Patients aged < 18 years were excluded. Patient data collected from the operative records and follow-up assessments were reviewed.

RESULTS

The mean age was 49 ± 9 years, and 64.1% of patients were male. One-hundred-and-fifty-two patients (89.4%) underwent aortic valve replacement with a mechanical valve and 18 (10.6%) with a bioprosthetic valve. The mean follow-up period was 8.1 ± 5.5 years. No operative mortality occurred, and in-hospital mortality occurred in one patient (0.6%). Ten late deaths occurred, with seven cardiac-related deaths. The overall survival rate was 95.4 ± 1.7%, 93.9 ± 2.3%, 90.6 ± 3.9%, and 73.2 ± 11.8% at 5, 10, 15, and 20 years, respectively. Freedom from major bleeding was 96.4 ± 1.6% at 5, 10, and 15 years, and 89.0 ± 7.3% at 20 years. Freedom from thromboembolic events was 98.7 ± 1.3%, 97.3 ± 1.9%, 90.5 ± 4.5%, and 79.0 ± 11.3% at 5, 10, 15, and 20 years, respectively. Freedom from valve-related reoperation was 99.4 ± 0.6% at 5 years, 97.8 ± 1.7% at 10 and 15 years, and 63.9 ± 14.5% at 20 years.

CONCLUSIONS

Patients aged < 60 years undergoing aortic valve replacement with a high mechanical valve implantation rate had favorable long-term outcomes.

Valvular heart disease: from mechanisms to management

Valvular heart disease is common and its prevalence is rapidly increasing worldwide. Effective medical therapies are insufficient and treatment was historically limited to the surgical techniques of valve repair or replacement, resulting in systematic underprovision of care to older patients and those with substantial comorbidities, frailty, or left ventricular dysfunction. Advances in imaging and surgical techniques over the past 20 years have transformed the management of valvular heart disease. Better understanding of the mechanisms and causes of disease and an increasingly extensive and robust evidence base provide a platform for the delivery of individualised treatment by multidisciplinary heart teams working within networks of diagnostic facilities and specialist heart valve centres. In this Series paper, we aim to provide an overview of the current and future management of valvular heart disease and propose treatment approaches based on an understanding of the underlying pathophysiology and the application of multidisciplinary treatment strategies to individual patients.

Transcatheter or surgical aortic valve implantation: 10-year outcomes of the NOTION trial

BACKGROUND AND AIMS

Transcatheter aortic valve implantation (TAVI) has become a viable treatment option for patients with severe aortic valve stenosis across a broad range of surgical risk. The Nordic Aortic Valve Intervention (NOTION) trial was the first to randomize patients at lower surgical risk to TAVI or surgical aortic valve replacement (SAVR). The aim of the present study was to report clinical and bioprosthesis outcomes after 10 years.

METHODS

The NOTION trial randomized 280 patients to TAVI with the self-expanding CoreValve (Medtronic Inc.) bioprosthesis (n = 145) or SAVR with a bioprosthesis (n = 135). The primary composite outcome was the risk of all-cause mortality, stroke, or myocardial infarction. Bioprosthetic valve dysfunction (BVD) was classified as structural valve deterioration (SVD), non-structural valve dysfunction (NSVD), clinical valve thrombosis, or endocarditis according to Valve Academic Research Consortium-3 criteria. Severe SVD was defined as (i) a transprosthetic gradient of 30 mmHg or more and an increase in transprosthetic gradient of 20 mmHg or more or (ii) severe new intraprosthetic regurgitation. Bioprosthetic valve failure (BVF) was defined as the composite rate of death from a valve-related cause or an unexplained death following the diagnosis of BVD, aortic valve re-intervention, or severe SVD.

RESULTS

Baseline characteristics were similar between TAVI and SAVR: age 79.2 ± 4.9 years and 79.0 ± 4.7 years (P = .7), male 52.6% and 53.8% (P = .8), and Society of Thoracic Surgeons score < 4% of 83.4% and 80.0% (P = .5), respectively. After 10 years, the risk of the composite outcome all-cause mortality, stroke, or myocardial infarction was 65.5% after TAVI and 65.5% after SAVR [hazard ratio (HR) 1.0; 95% confidence interval (CI) 0.7-1.3; P = .9], with no difference for each individual outcome. Severe SVD had occurred in 1.5% and 10.0% (HR 0.2; 95% CI 0.04-0.7; P = .02) after TAVI and SAVR, respectively. The cumulative incidence for severe NSVD was 20.5% and 43.0% (P < .001) and for endocarditis 7.2% and 7.4% (P = 1.0) after TAVI and SAVR, respectively. No patients had clinical valve thrombosis. Bioprosthetic valve failure occurred in 9.7% of TAVI and 13.8% of SAVR patients (HR 0.7; 95% CI 0.4-1.5; P = .4).

CONCLUSIONS

In patients with severe AS and lower surgical risk randomized to TAVI or SAVR, the risk of major clinical outcomes was not different 10 years after treatment. The risk of severe bioprosthesis SVD was lower after TAVR compared with SAVR, while the risk of BVF was similar.

Transcatheter Aortic Valve Implantation to Treat Degenerated Aortic, Mitral and Tricuspid Bioprosthesis

Transcatheter aortic valve implantation (TAVI) is now well established as the treatment of choice for patients with native aortic valve stenosis who are high or intermediate risk for surgical aortic valve replacement. Recent data has also supported the use of TAVI in patients at low surgical risk and also in anatomical subsets that were previously felt to be contra-indicated including bicuspid aortic valves and aortic regurgitation. With advancements and refinements in procedural techniques, the application of this technology has now been further expanded to include the management of degenerated bioprosthesis. After the demonstration of feasibility and safety in the management of degenerated aortic bioprosthetic valves, mitral and tricuspid bioprosthetic valve treatment is now also well-established and provides an attractive alternative to performing redo surgery. In this review, we appraise the latest clinical evidence and highlight procedural considerations when utilising TAVI technology in the management of degenerated aortic, mitral or tricuspid prosthesis.

Aortic valve replacement in non-elderly: the gap between reality, guidelines and evidence

OBJECTIVES

There are several treatment options for non-elderly adults (18-60 years) in need of aortic valve replacement (AVR): a mechanical or biological substitute, a homograft, the Ross procedure or nowadays even transcatheter aortic valve replacement. This study evaluated the current opinions and practices of cardiac surgeons and cardiologists concerning AVR strategies in this patient group.

METHODS

A 43-item online survey was sent out to several scientific organizations, individual cardiac surgeons, cardiologists and residents/fellows worldwide.

RESULTS

Two hundred twenty-two physicians from 33 different countries answered the survey. The UK (24%), Belgium (23%) and North America (22%) are best represented. A mechanical valve is the most frequently used substitute in non-elderly. With increasing patient age, the popularity of a biological valve increases. Transcatheter aortic valve replacement and the Ross procedure are each used in <10% of this cohort. Only 12% of the cardiac surgeons has experience with the Ross surgery. In 23%, the patient seems not to be involved in the decision on the type of valve substitute.

CONCLUSIONS

The preferred surgical treatment for non-elderly patients in need of AVR differs widely. To enable a shared decision-making process including patient preferences, there is more need for collaboration between cardiac departments, as well as education and scientific research about patient-centred outcomes of the different AVR techniques.

Feasibility of Coronary Access Following Redo-TAVR for Evolut Failure: A Computed Tomography Simulation Study

BACKGROUND

Coronary accessibility following redo-transcatheter aortic valve replacement (redo-TAVR) is increasingly important, particularly in younger low-risk patients. This study aimed to predict coronary accessibility after simulated Sapien-3 balloon-expandable valve implantation within an Evolut supra-annular, self-expanding valve using pre-TAVR computed tomography (CT) imaging.

METHODS

A total of 219 pre-TAVR CT scans from the Evolut Low-Risk CT substudy were analyzed. Virtual Evolut and Sapien-3 valves were sized using CT-based diameters. Two initial Evolut implant depths were analyzed, 3 and 5 mm. Coronary accessibility was evaluated for 2 Sapien-3 in Evolut implant positions: Sapien-3 outflow at Evolut node 4 and Evolut node 5.

RESULTS

With a 3-mm initial Evolut implant depth, suitable coronary access was predicted in 84% of patients with the Sapien-3 outflow at Evolut node 4, and in 31% of cases with the Sapien-3 outflow at Evolut node 5 (P<0.001). Coronary accessibility improved with a 5-mm Evolut implant depth: 97% at node 4 and 65% at node 5 (P<0.001). When comparing 3- to 5-mm Evolut implant depth, sinus sequestration was the lowest with Sapien-3 outflow at Evolut node 4 (13% versus 2%; P<0.001), and the highest at Evolut node 5 (61% versus 32%; P<0.001).

CONCLUSIONS

Coronary accessibility after Sapien-3 in Evolut redo-TAVR relates to the initial Evolut implant depth, the Sapien-3 outflow position within the Evolut, and the native annular anatomy. This CT-based quantitative analysis may provide useful information to inform and refine individualized preprocedural CT planning of the initial TAVR and guide lifetime management for future coronary access after redo-TAVR.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02701283.

Differences in blood flow dynamics between balloon- and self-expandable valves in patients with aortic stenosis undergoing transcatheter aortic valve replacement

BACKGROUND

The differences in pre- and early post-procedural blood flow dynamics between the two major types of bioprosthetic valves, the balloon-expandable valve (BEV) and self-expandable valve (SEV), in patients with aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR), have not been investigated. We aimed to investigate the differences in blood flow dynamics between the BEV and SEV using four-dimensional flow cardiovascular magnetic resonance (4D flow CMR).

METHODS

We prospectively examined 98 consecutive patients with severe AS who underwent TAVR between May 2018 and November 2021 (58 BEV and 40 SEV) after excluding those without CMR because of a contraindication, inadequate imaging from the analyses, or patients' refusal. CMR was performed in all participants before (median interval, 22 [interquartile range (IQR) 4-39] days) and after (median interval, 6 [IQR 3-6] days) TAVR. We compared the changes in blood flow patterns, wall shear stress (WSS), and energy loss (EL) in the ascending aorta (AAo) between the BEV and SEV using 4D flow CMR.

RESULTS

The absolute reductions in helical flow and flow eccentricity were significantly higher in the SEV group compared in the BEV group after TAVR (BEV: - 0.22 ± 0.86 vs. SEV: - 0.85 ± 0.80, P < 0.001 and BEV: - 0.11 ± 0.79 vs. SEV: - 0.50 ± 0.88, P = 0.037, respectively); there were no significant differences in vortical flow between the groups. The absolute reduction of average WSS was significantly higher in the SEV group compared to the BEV group after TAVR (BEV: - 0.6 [- 2.1 to 0.5] Pa vs. SEV: - 1.8 [- 3.5 to - 0.8] Pa, P = 0.006). The systolic EL in the AAo significantly decreased after TAVR in both the groups, while the absolute reduction was comparable between the groups.

CONCLUSIONS

Helical flow, flow eccentricity, and average WSS in the AAo were significantly decreased after SEV implantation compared to BEV implantation, providing functional insights for valve selection in patients with AS undergoing TAVR. Our findings offer valuable insights into blood flow dynamics, aiding in the selection of valves for patients with AS undergoing TAVR. Further larger-scale studies are warranted to confirm the prognostic significance of hemodynamic changes in these patients.

Antithrombotic therapy with Transcatheter aortic valve replacement

Aortic valve replacement is a necessary management strategy for patients with severe aortic stenosis. The use of transaortic valve replacement (TAVR) has increased significantly over the last decade and now exceeds traditional surgical aortic valve replacement. Since the valve systems used in TAVR consist of bioprosthetic valve tissue encased in a metal stent frame, antithrombotic therapy recommendations cannot be extrapolated from prior data with differently constructed surgical bioprosthetic or mechanical valves. Data on the use of antithrombotic therapy with TAVR are a rapidly developing area of medicine. Choice of agents depends on several patient factors. Patients undergoing TAVR also have a relatively high incidence of subclinical valve thrombosis. The clinical impact of this phenomenon and the implications for antithrombotic therapy continue to evolve. It is critical for clinicians who treat patients undergoing TAVR to have a firm understanding of practice guidelines, the evolving evidence, and its implications for the use of antithrombotic therapy in these patients.

Sternal-Sparing Surgical Options in Combined Aortic Valve and Coronary Artery Disease: Proof of Concept

OBJECTIVE

The standard management of concomitant aortic valve (AV) and coronary artery disease has been coronary artery bypass and AV replacement (AVR). With the advent of minimally invasive options, many isolated lesions have been successfully managed using a sternal-sparing approach. In our institution, patients with isolated AV disease are offered minimally invasive surgical or transcatheter AVR, and those with isolated coronary artery disease are routinely managed with robotic totally endoscopic coronary artery bypass or percutaneous coronary intervention. Various combinations of these techniques can be used when a sternal-sparing posture is desired because of patient risk or preference. The aim of this study was to review the outcomes in patients with combined AV and coronary disease who were managed using sternal-sparing approaches.

METHODS

We reviewed the records of 10 patients in our minimally invasive surgical database who presented with concomitant AV and coronary artery disease and underwent combined sternal-sparing management of these 2 lesions using various combinations of minimally invasive approaches.

RESULTS

Four patients had totally endoscopic coronary artery bypass and minimally invasive AVR at the same time, 2 patients underwent transcatheter AVR followed by totally endoscopic coronary artery bypass, and 4 patients underwent minimally invasive AVR with percutaneous coronary intervention. There was no 30-day mortality. The duration of postoperative surgical hospital stay was 3.1 ± 0.9 days.

CONCLUSIONS

Sternal-sparing approaches in combined AV and coronary artery disease are feasible with patient-specific treatment selection of minimally invasive techniques.

A bench study of balloon-expandable valves for the treatment of self-expanding valve failure

BACKGROUND

Coronary obstruction and access are concerns in patients undergoing redo transcatheter aortic valve implantation (TAVI).

AIMS

We sought to assess the neoskirt height, leaflet overhang, leaflet deflection,and transcatheter heart valve (THV) expansion and performance, at 2 different implant depths, of the SAPIEN 3 Ultra (S3U) within the ACURATE neo2 (ACn2) THV.

METHODS

An in vitro study was performed with a 23 mm S3U deployed within a small (S) ACn2 and a 26 mm S3U deployed within a medium (M) and a large (L) ACn2. The S3U outflow was positioned at the top of the ACn2 crown (low implant) and at the base of the commissural post of the ACn2 (high implant). Testing was performed under physiological conditions as per ISO-5840-3 standard.

RESULTS

The neoskirt height was shorter when the S3U outflow was positioned at a low implantation depth (S: 9.6 mm, M: 12.2 mm, L: 13.8 mm vs S: 15.2 mm, M: 15.1 mm, L: 17.8 mm ACn2 for high implants). Hydrodynamic performance was acceptable for all configurations. Leaflet overhang was <50% for all configurations except the low implant of the 26 mm S3U in the L ACn2 (77.6%). There was a gap from the side of the neoskirt to the outer border of the THV frame which was >2 mm for all configurations. The S3U was underexpanded for all configurations, and the achieved area was 77.9%-92.9% of the expected nominal area.

CONCLUSIONS

Redo TAVI with an S3U within an ACn2 has favourable hydrodynamics and moderate leaflet overhang. Importantly, the design of the ACn2 results in a neoskirt that is not deflected all the way to the outer dimensions of the THV, hence creating a space that facilitates coronary flow and access.

Sutureless vs. rapid-deployment valve: a systemic review and meta-analysis for a direct comparison of intraoperative performance and clinical outcomes

Background

Sutureless and rapid-deployment valves are bioprostheses anchoring within the aortic annulus with few sutures, and they act as a hybrid of conventional surgical and transcatheter valves under aortic valve replacement. Considering that the 3F Enable valve is now off-market, the only two sutureless and rapid-deployment valves available on the world marketplace are the Perceval and Intuity valves. However, a direct comparison of the function of these two valves eludes researchers.

Purpose

Against this background, we performed this systematic review and meta-analysis comparing the intraoperative performance and early clinical outcomes between the Perceval valve and the Intuity valve under sutureless and rapid-deployment aortic valve replacement.

Methods

We systematically searched electronic databases through PubMed/MEDLINE, OvidWeb, Web of Science, and Cochrane Central Register of Controlled Trials (from the establishment of the database to November 17, 2022, without language restriction) for studies comparing the sutureless valve (the Perceval) and the rapid-deployment valve (the Intuity) under aortic valve replacement. Our primary outcomes were early mortality and postoperative transvalvular pressure gradients. The secondary outcomes were defined to include aortic cross-clamp and cardiopulmonary bypass time, paravalvular leak (any paravalvular leak, moderate-to-severe paravalvular leak) after aortic valve replacement, need for pacemaker implantation, postoperative neurological events (stroke), and intensive care unit stay.

Results

This meta-analysis included ten non-randomized trials with 3,526 patients enrolled (sutureless group = 1,772 and rapid-deployment group = 1,754). Quality assessments were performed, with the mean scores of the studies reading 6.90 (SD = 0.99) out of 9 according to the Newcastle-Ottawa Scale. Compared with rapid-deployment aortic valve replacement, sutureless aortic valve replacement was associated with higher mean and peak transvalvular pressure gradients postoperatively. In contrast, aortic cross-clamp and cardiopulmonary time were needed less in sutureless aortic valve replacement vs. rapid-deployment aortic valve replacement. There was no evidence of significant publication bias observed by the funnel plot and Egger's test.

Conclusions

For postoperative hemodynamics, sutureless aortic valve replacement was associated with increased mean and peak transvalvular pressure gradients compared with rapid-deployment aortic valve replacement. In sharp contrast, sutureless aortic valve replacement significantly reduced the amount of time needed for fixing the aortic cross-clamp and the cardiopulmonary bypass procedure.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42022343884.

Coronary Obstruction during Valve-in-Valve Transcatheter Aortic Valve Replacement: Pre-Procedural Risk Evaluation, Intra-Procedural Monitoring, and Follow-Up

Valve-in-valve (ViV) transcatheter aortic valve replacement (TAVR) is emerging as an effective treatment for patients with symptomatically failing bioprosthetic valves and a high prohibitive surgical risk; a longer life expectancy has led to a higher demand for these valve reinterventions due to the increased possibilities of outliving the bioprosthetic valve's durability. Coronary obstruction is the most feared complication of valve-in-valve (ViV) TAVR; it is a rare but life-threatening complication and occurs most frequently at the left coronary artery ostium. Accurate pre-procedural planning, mainly based on cardiac computed tomography, is crucial to determining the feasibility of a ViV TAVR and to assessing the anticipated risk of a coronary obstruction and the eventual need for coronary protection measures. Intraprocedurally, the aortic root and a selective coronary angiography are useful for evaluating the anatomic relationship between the aortic valve and coronary ostia; transesophageal echocardiographic real-time monitoring of the coronary flow with a color Doppler and pulsed-wave Doppler is a valuable tool that allows for a determination of real-time coronary patency and the detection of asymptomatic coronary obstructions. Because of the risk of developing a delayed coronary obstruction, the close postprocedural monitoring of patients at a high risk of developing coronary obstructions is advisable. CT simulations of ViV TAVR, 3D printing models, and fusion imaging represent the future directions that may help provide a personalized lifetime strategy and tailored approach for each patient, potentially minimizing complications and improving outcomes.

Contemporary issues and lifetime management in patients underwent transcatheter aortic valve replacement

Latest clinical trials have indicated favorable outcomes following transcatheter aortic valve replacement (TAVR) in low surgical risk patients with severe aortic stenosis. However, there are unanswered questions particularly in younger patients with longer life expectancy. While current evidence are limited to short duration of clinical follow-up, there are certain factors which may impair patients clinical outcomes and quality-of-life at long-term. Contemporary issues in the current TAVR era include prosthesis-patient mismatch, heart failure hospitalization, subclinical thrombosis, future coronary access, and valve durability. In this review, the authors review available evidence and discuss each remaining issues and theoretical treatment strategies in lifetime management of TAVR patients.

Changes in aortic valve replacement procedures in Denmark from 2008 to 2020

INTRODUCTION

Since 2007, transcatheter aortic valve implantation (TAVI) has emerged as another treatment strategy for severe symptomatic aortic stenosis (AS) compared with surgical aortic valve replacement (SAVR). The objectives were to compare annual rates of aortic valve replacement (AVR) procedures performed in Denmark in the era of TAVI and to assess proportion of AVRs stratified by age with use of age recommendations presented in current guidelines.

METHODS

Using Danish nationwide registries, we identified first-time AVRs between 2008 and 2020. Patients who were not diagnosed with AS prior to AVR were excluded RESULTS: The rate of AVRs increased by 39% per million inhabitants from 2008 to 2020. TAVI has steadily increased since 2008, accounting for 64.2% of all AVRs and 72.5% of isolated AVRs by 2020. Number of isolated SAVRs decreased from 2014 and onwards. The proportion of TAVI increased significantly across age groups (<75 and ≥75 years of age, p_trend<0.001), and TAVI accounted for 91.5% of isolated AVR procedures in elderly patients (aged ≥75 years). Length of hospital stay were significantly reduced for all AVRs during the study period (p_trend all<0.001).

CONCLUSIONS

The number of AVRs increased from 2008 to 2020 due to adaptation of TAVI, which represented 2/3 of AVRs and more than 70% of isolated AVRs. In elderly patients, the increased use of AVR procedures was driven by TAVI, in agreement with the age recommendations in current guidelines; however, TAVI was used more frequently in patients aged <75 years, accompanied by a flattening use of SAVR.

Temporal changes of patient characteristics over 12 years in a single-center transcatheter aortic valve implantation cohort

BACKGROUND

Beneficial results of transcatheter aortic valve implantation (TAVI) compared to surgical aortic valve replacement (SAVR) in patients at all risk strata have led to substantial changes in guideline recommendations for valvular heart disease.

AIM

To examine influence of these guideline changes on a real-world TAVI cohort, we evaluated how risk profiles and outcomes of TAVI patients developed in our single-center patient cohort over a period of 12 years.

METHODS

Baseline, procedural and 30-day outcome parameters of TAVI patients were retrospectively compared between three time periods (period 1: 2008-2012, period 2: 2013-2017, period 3: 2018-2020).

RESULTS

Between 03/2008 and 12/2020, a total of 3678 patients underwent TAVI at our center. The median age was 81.1 years (25th, 75th percentile: 76.7, 84.9) with no significant change over time. The EuroSCORE II showed a continuous and significant decline from 5.3% (3.3, 8.6) in period 1 to 2.8% (1.7, 5.0) in period 3 (p < 0.001). Furthermore, rates of permanent pacemaker implantation, acute kidney injury, and paravalvular leakage ≥ moderate continuously declined over time. Accordingly, the 30-day mortality fell from 9.3% in period 1 to 4.3% in period 3 (p < 0.001).

CONCLUSION

Despite substantial guideline alterations, median patient age remained largely unchanged in our TAVI cohort over the past 12 years. Therefore, increased age still appears to be the main reason to choose TAVI over SAVR. However, risk profiles declined substantially. Significant improvements in early outcomes suggest favorable influence of less invasive access routes, improved device platforms and growing user experience.

Structural Valve Deterioration After Self-Expanding Transcatheter or Surgical Aortic Valve Implantation in Patients at Intermediate or High Risk

Importance

The frequency and clinical importance of structural valve deterioration (SVD) in patients undergoing self-expanding transcatheter aortic valve implantation (TAVI) or surgery is poorly understood.

Objective

To evaluate the 5-year incidence, clinical outcomes, and predictors of hemodynamic SVD in patients undergoing self-expanding TAVI or surgery.

Design, Setting, and Participants

This post hoc analysis pooled data from the CoreValve US High Risk Pivotal (n = 615) and SURTAVI (n = 1484) randomized clinical trials (RCTs); it was supplemented by the CoreValve Extreme Risk Pivotal trial (n = 485) and CoreValve Continued Access Study (n = 2178). Patients with severe aortic valve stenosis deemed to be at intermediate or increased risk of 30-day surgical mortality were included. Data were collected from December 2010 to June 2016, and data were analyzed from December 2021 to October 2022.

Interventions

Patients were randomized to self-expanding TAVI or surgery in the RCTs or underwent self-expanding TAVI for clinical indications in the nonrandomized studies.

Main Outcomes and Measures

The primary end point was the incidence of SVD through 5 years (from the RCTs). Factors associated with SVD and its association with clinical outcomes were evaluated for the pooled RCT and non-RCT population. SVD was defined as (1) an increase in mean gradient of 10 mm Hg or greater from discharge or at 30 days to last echocardiography with a final mean gradient of 20 mm Hg or greater or (2) new-onset moderate or severe intraprosthetic aortic regurgitation or an increase of 1 grade or more.

Results

Of 4762 included patients, 2605 (54.7%) were male, and the mean (SD) age was 82.1 (7.4) years. A total of 2099 RCT patients, including 1128 who received TAVI and 971 who received surgery, and 2663 non-RCT patients who received TAVI were included. The cumulative incidence of SVD treating death as a competing risk was lower in patients undergoing TAVI than surgery (TAVI, 2.20%; surgery, 4.38%; hazard ratio [HR], 0.46; 95% CI, 0.27-0.78; P = .004). This lower risk was most pronounced in patients with smaller annuli (23 mm diameter or smaller; TAVI, 1.32%; surgery, 5.84%; HR, 0.21; 95% CI, 0.06-0.73; P = .02). SVD was associated with increased 5-year all-cause mortality (HR, 2.03; 95% CI, 1.46-2.82; P < .001), cardiovascular mortality (HR, 1.86; 95% CI, 1.20-2.90; P = .006), and valve disease or worsening heart failure hospitalizations (HR, 2.17; 95% CI, 1.23-3.84; P = .008). Predictors of SVD were developed from multivariate analysis.

Conclusions and Relevance

This study found a lower rate of SVD in patients undergoing self-expanding TAVI vs surgery at 5 years. Doppler echocardiography was a valuable tool to detect SVD, which was associated with worse clinical outcomes.

Trial Registration

ClinicalTrials.gov Identifiers: NCT01240902, NCT01586910, and NCT01531374.

Coronary access following ACURATE neo implantation for transcatheter aortic valve-in-valve implantation: Ex vivo analysis in patient-specific anatomies

Background

Coronary access after transcatheter aortic valve implantation (TAVI) with supra-annular self-expandable valves may be challenging or un-feasible. There is little data concerning coronary access following transcatheter aortic valve-in-valve implantation (ViV-TAVI) for degenerated surgical bioprosthesis.

Aims

To evaluate the feasibility and challenge of coronary access after ViV-TAVI with the supra-annular self-expandable ACURATE neo valve.

Materials and methods

Sixteen patients underwent ViV-TAVI with the ACURATE neo valve. Post-procedural computed tomography (CT) was used to create 3D-printed life-sized patient-specific models for bench-testing of coronary cannulation. Primary endpoint was feasibility of diagnostic angiography and PCI. Secondary endpoints included incidence of challenging cannulation for both diagnostic catheters (DC) and guiding catheters (GC). The association between challenging cannulations with aortic and transcatheter/surgical valve geometry was evaluated using pre and post-procedural CT scans.

Results

Diagnostic angiography and PCI were feasible for 97 and 95% of models respectively. All non-feasible procedures occurred in ostia that underwent prophylactic “chimney” stenting. DC cannulation was challenging in 17% of models and was associated with a narrower SoV width (30 vs. 35 mm, p < 0.01), STJ width (28 vs. 32 mm, p < 0.05) and shorter STJ height (15 vs. 17 mm, p < 0.05). GC cannulation was challenging in 23% of models and was associated with narrower STJ width (28 vs. 32 mm, p < 0.05), smaller transcatheter-to-coronary distance (5 vs. 9.2 mm, p < 0.05) and a worse coronary-commissural overlap angle (14.3° vs. 25.6^o, p < 0.01). Advanced techniques to achieve GC cannulation were required in 22/64 (34%) of cases.

Conclusion

In this exploratory bench analysis, diagnostic angiography and PCI was feasible in almost all cases following ViV-TAVI with the ACURATE neo valve. Prophylactic coronary stenting, higher implantation, narrower aortic sinus dimensions and commissural misalignment were associated with an increased challenge of coronary cannulation.

Transcatheter Versus Surgical Aortic Valve Replacement in Young, Low-risk Patients with Severe Aortic Stenosis

Aortic stenosis is a common form of acquired degenerative valvular disease associated with poor survival after the onset of symptoms. Treatment options for patients with aortic stenosis in addition to medical therapy include surgical aortic valve replacement (SAVR) with either tissue or mechanical valves, or transcatheter aortic valve replacement (TAVR) with either balloon-expandable or self-expanding valves via either transfemoral or alternative access routes. In this review, the authors discuss the current evidence and special considerations regarding the use of TAVR versus SAVR in the management of severe aortic stenosis in young (<65 years of age), low-risk patients, highlighting the history of aortic stenosis treatment, the current guidelines and recommendations, and important issues that remain to be addressed. Ultimately, until ongoing clinical trials with long-term follow-up data shed light on whether interventions for aortic stenosis can be broadened to a low-risk population, TAVR in young, low-risk patients should be undertaken with caution and with guidance from a multidisciplinary heart team.

TAVR for All? The Surgical Perspective

In spite of the noninferiority of transcatheter aortic valve replacement (TAVR) in high- and intermediate-risk patients, there are still obstacles that need to be overcome before the procedure is further expanded and clinically integrated. The lack of evidence on the long-term durability of the bioprostheses used for TAVR remains of particular concern. In addition, surgery may be preferred over TAVR in patients with bicuspid aortic valve (BAV) or with concomitant pathologies such as other valve diseases (mitral regurgitation/tricuspid regurgitation), aortopathy, and coronary artery disease. In this review, we discuss and summarize relevant data from clinical trials, current trends, and remaining obstacles, and provide our perspective on the indications for the expansion of TAVR.

The role of mechanical valves in the aortic position in the era of bioprostheses and TAVR: Evidence-based appraisal and focus on the On-X valve

Patients who need a prosthetic aortic heart valve may decide, working with their cardiologist and cardiac surgeon, among a variety of options: surgical or transcatheter approach, bioprosthetic or mechanical valve, or a Ross procedure if suitable to their age and anatomy. This review article examines the evidence for survival benefit with mechanical aortic valves, discusses bioprosthetic structural valve degeneration and its consequences, and considers the risks of redo aortic valve surgery or subsequent valve-in-valve (ViV) transcatheter intervention. It highlights the unique characteristics of the On-X aortic valve, including the US Food and Drug Administration approved and American College of Cardiology/American Heart Association guideline supported reduced anticoagulation target INR of 1.5 to 2.0, and discusses the PROACT Xa trial comparing apixaban vs warfarin anticoagulation. The choice of prosthetic valve should be individualized, carefully considering each patient's unique circumstances. In that context, the On-X aortic valve offers a potential lifetime solution without need for a repeat operation, while minimizing the risks of long-term anticoagulation. In an era of enthusiasm for bioprosthetic and transcatheter-based approaches, the option of a second-generation bileaflet mechanical valve with optimized hemodynamics-the On-X aortic valve-may well align with patient expectations.

Prevention of coronary obstruction in patients at risk undergoing transcatheter aortic valve implantation: the Hamburg BASILICA experience

OBJECTIVES

This study aimed to assess the clinical outcome of the bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary obstruction (BASILICA) technique in a single-center patient cohort considered at high or prohibitive risk of transcatheter aortic valve implantation (TAVI)-induced coronary obstruction.

METHODS

Between October 2019 and January 2021, a total of 15 consecutive patients (age 81.0 [78.1, 84.4] years; 53.3% female; EuroSCORE II 10.6 [6.3, 14.8] %) underwent BASILICA procedure prior to TAVI at our institution. Indications for TAVI were degeneration of stented (n = 12, 80.0%) or stentless (n = 1, 6.7%) bioprosthetic aortic valves, or calcific stenosis of native aortic valves (n = 2, 13.3%), respectively. Individual risk of TAVI-induced coronary obstruction was assessed by pre-procedural computed tomography analysis. Procedural and 30-day outcomes were documented in accordance with Valve Academic Research Consortium (VARC)-2 criteria.

RESULTS

BASILICA was attempted for single left coronary cusp in 12 patients (80.0%), for single right coronary cusp in 2 patients (13.3%), and for both cusps in 1 patient (6.7%), respectively. The procedure was feasible in 13 patients (86.7%) resulting in effective prevention of coronary obstruction, whilst TAVI was performed without prior successful bioprosthetic leaflet laceration in two patients (13.3%). In one of these patients (6.7%), additional chimney stenting immediately after TAVI was performed. No all-cause deaths or strokes were documented after 30 days.

CONCLUSION

The BASILICA technique appears to be a feasible, safe and effective concept to avoid iatrogenic coronary artery obstruction during TAVI in both native and bioprosthetic valves of patients at high or prohibitive risk. ClinicalTrials.gov Identifier: NCT04227002 (Hamburg AoRtic Valve cOhoRt).

Transcatheter Aortic Valve Implantation in Younger Patients: A New Challenge

The number of aortic stenosis patients in Western countries is increasing, along with better life conditions and expectancies. Presently, the volume of percutaneous transcatheter aortic valve implantations (TAVIs) is incessantly increasing, and has already overcome the surgical replacement procedure volume. According to the literature, TAVI is a feasible procedure even among low surgical risk patients, and American guidelines have extended the indications for TAVI, including shifting patient evaluations from high/low STS scores to old/young patients, a "paradigm shift" of aortic stenosis evaluation. As a result, low-risk young (<75 years-old) population management could be the next challenge in cardiology. To manage the life conditions of a 65 year old patient affected by aortic stenosis who is undergoing TAVI, one of the most crucial issue will be bioprosthesis durability and the appropriate intervention to make in cases of valve dysfunction or failure.