Risk of Coronary Obstruction and Feasibility of Coronary Access After Repeat Transcatheter Aortic Valve Replacement With the Self-Expanding Evolut Valve: A Computed Tomography Simulation Study

Coronary Artery Disease and Severe Aortic Stenosis: Contemporary Treatment Options for Patients Undergoing Transcatheter Aortic Valve Implantation

Approximately 50% of individuals eligible for transcatheter aortic valve implantation (TAVI) have coronary artery disease (CAD). The influence of CAD, both its prevalence and severity, on post-TAVI clinical results has yielded conflicting findings. Recent research has shown positive results for the use of computed tomography angiography and functional percutaneous evaluation of coronary lesions in the pre-TAVI assessment, besides the classic coronary angiography. As we anticipate the outcomes of current randomized studies, it has become common practice to perform invasive revascularization on TAVI patients with obstructive CAD. Furthermore, there is a lack of comprehensive data about the occurrence, features, and treatment of coronary incidents after TAVI. There is also growing concern about the possible difficulties in accessing the coronary arteries in patients who need coronary angiography with or without intervention after TAVI. This review presents a comprehensive analysis of the contemporary treatment options of CAD in patients undergoing TAVI. In this context, it examines the incidence of CAD in TAVI candidates; its clinical significance; the assessment and management of CAD before, concomitant, and after the procedure, including patients' unresolved concerns; and possible future aspects.

Laser ablation for preventing coronary obstruction and maintaining coronary access in redo-TAVR: A proof of concept

BACKGROUND

Redo-transcatheter aortic valve replacement (TAVR) is a promising treatment for transcatheter aortic valve degeneration, becoming increasingly relevant with an aging population. In redo-TAVR, the leaflets of the initial (index) transcatheter aortic valve (TAV) are displaced vertically when the second TAV is implanted, creating a cylindrical cage that can impair coronary cannulation and flow. Preventing coronary obstruction and maintaining coronary access is essential, especially in young and low-risk patients undergoing TAVR. This study aimed to develop a new leaflet modification strategy using laser ablation to prevent coronary obstruction and facilitate coronary access after repeat TAVR.

METHODS

To evaluate the feasibility of the leaflet modification technique using laser ablation, the initial phase of this study involved applying a medical-grade ultraviolet laser for ablation through pericardial tissue. Following this intervention, computational fluid dynamics simulations were utilized to assess the efficacy of the resulting perforations in promoting coronary flow. These simulations played a crucial role in understanding the impact of the modifications on blood flow patterns, ensuring these changes would facilitate the restoration of coronary circulation.

RESULTS

Laser ablation of pericardium leaflets was successful, demonstrating the feasibility of creating openings in the TAV leaflets. Flow simulation results show that ablation of index valve leaflets can effectively mitigate the flow obstruction caused by sinus sequestration in redo-TAVR, with the extent of restoration dependent on the number and location of the ablated openings.

CONCLUSIONS

Laser ablation could be a viable method for leaflet modification in redo-TAVR, serving as a new tool in interventional procedures.

Transcatheter Aortic Valve Replacement is Ready for Most Low-risk Patients: A Systematic Review of the Literature

Transcatheter aortic valve replacement (TAVR) has undergone rapid expansion, emerging as a viable therapeutic option for low-risk patients in lieu of surgical aortic valve replacement. This paper aims to provide a review of the scientific evidence concerning TAVR in low-risk patients, encompassing both observational and clinical trial data. Furthermore, a substantial proportion of low-risk patients possesses a bicuspid aortic valve, necessitating careful examination of the pertinent anatomic and clinical considerations to TAVR that is highlighted in this review. Additionally, the review expands upon some of the unique challenges associated with alternate access in low-risk patients evaluated for TAVR. Last, this review outlines the pivotal role of a multidisciplinary heart team approach in the execution of all TAVR procedures and the authors' vision of 'minimalist TAVR' as a new era in low-risk TAVR.

Fluid-Solid Interaction Analysis for Developing In-Situ Strain and Flow Sensors for Prosthetic Valve Monitoring

Transcatheter aortic valve implantation (TAVI) was initially developed for adult patients, but there is a growing interest to expand this procedure to younger individuals with longer life expectancies. However, the gradual degradation of biological valve leaflets in transcatheter heart valves (THV) presents significant challenges for this extension. This study aimed to establish a multiphysics computational framework to analyze structural and flow measurements of TAVI and evaluate the integration of optical fiber and photoplethysmography (PPG) sensors for monitoring valve function. A two-way fluid-solid interaction (FSI) analysis was performed on an idealized aortic vessel before and after the virtual deployment of the SAPIEN 3 Ultra (S3) THV. Subsequently, an analytical analysis was conducted to estimate the PPG signal using computational flow predictions and to analyze the effect of different pressure gradients and distances between PPG sensors. Circumferential strain estimates from the embedded optical fiber in the FSI model were highest in the sinus of Valsalva; however, the optimal fiber positioning was found to be distal to the sino-tubular junction to minimize bending effects. The findings also demonstrated that positioning PPG sensors both upstream and downstream of the bioprosthesis can be used to effectively assess the pressure gradient across the valve. We concluded that computational modeling allows sensor design to quantify vessel wall strain and pressure gradients across valve leaflets, with the ultimate goal of developing low-cost monitoring systems for detecting valve deterioration.

Sutureless Valves, a "Wireless" Option for Patients With Aortic Valve Disease: JACC State-of-the-Art Review

Transcatheter technologies triggered the recent revision of the guidelines that progressively widened the indications for the treatment of aortic stenosis. On the surgical realm, a technology avoiding the need for sutures to anchor the prosthesis to the aortic annulus has been developed with the aim to reduce the duration of cardiopulmonary bypass and simplify the process of valve implantation. In addition to a transcatheter aortic valve replacement (TAVR)-like stent that exerts a radial force, these so-called "rapid deployment valves" or "sutureless valves" for aortic valve replacement also have cuffs to improve sealing and reduce the risk of paravalvular leak. Despite promising, the actual advantage of sutureless valves over traditional surgical procedures (surgical aortic valve replacement) or TAVR is still debated. This review summarizes the current comparative evidence reporting outcomes of "sutureless valves" for aortic valve replacement to TAVR and surgical aortic valve replacement in the treatment of aortic valve stenosis.

Coronary access after repeat transcatheter aortic valve replacement in patients of small body size: A simulation study

BACKGROUND

Coronary artery access after repeat transcatheter aortic valve replacement (TAV-in-TAV) is reportedly more difficult because leaflet displacement of the first transcatheter heart valve (THV) impairs coronary cannulation; however, its effects in small patients are unknown. This study aimed to simulate coronary accessibility after TAV-in-TAV in patients of small body size.

METHODS

We retrospectively analyzed computed tomography scans after initial THV implantation and classified patients by THV and coronary artery location, valve-to-aorta distance, and valve-to-coronary distance. Risks were compared between the SAPIEN and CoreValve/Evolut series, among THV generations, and between bicuspid and tricuspid aortic valves in the CoreValve/Evolut series.

RESULTS

A total of 254 patients (SAPIEN series, n = 164; CoreValve/Evolut series, n = 90) were enrolled. The average body surface area of the patients was 1.44 m2. Patients were classified as "feasible" (26%), "theoretically feasible with low risk" (19.7%), "theoretically feasible with high risk" (8.7%), or "unfeasible" (45.8%). The "unfeasible" rate was significantly higher in the CoreValve/Evolut series than in the SAPIEN series (78.9% vs 26.2%; P < .001). A significantly higher "unfeasible" rate was identified in the current model of SAPIEN (SAPIEN, 8.3%; SAPIENXT, 1.8%; SAPIEN3, 48.2%; P < .001), but not in the CoreValve/Evolut series (CoreValve, 83.3%; Evolut R, 80.0%; Evolut PRO, 71.4%; P = .587). Patients with a bicuspid aortic valve had a lower "unfeasible" rate compared to those with a tricuspid aortic valve (60.0% vs 86.2%; P = .014).

CONCLUSIONS

Patients of small body size may have a high probability of "unfeasible" coronary access after TAV-in-TAV, especially when treated with current high-frame devices, suggesting the need for careful strategic planning for initial THV implantation.

Temporal trends with the Evolut family of self-expanding transcatheter heart valves: A single-center experience

BACKGROUND

The Evolut self-expanding valve (SEV) systems (Medtronic), were designed to accommodate varying valve sizes and reduce paravalvular leak (PVL) while maintaining a low delivery profile. These systems have evolved between product generations, alongside valve deployment techniques changing over time.

AIMS

This study aimed to examine whether these changes impacted clinical outcomes.

METHODS

EPROMPT is a prospective, investigator-initiated, postmarketing registry of consecutive patients undergoing transfemoral transcatheter aortic valve replacement (TAVR) using the Evolut PRO/PRO+ SEV system. A total of 300 patients were divided into three consecutive cohorts of 100 patients according to implantation date (January to October 2018, November 2018 to July 2020, and August 2020 to November 2021). Procedural and clinical outcomes over these time periods were compared.

RESULTS

Valve Academic Research Consortium (VARC)-2 device implantation success improved over time (70.0% vs. 78.0% vs. 88.8%, p = 0.01), with a similar trend for VARC-3 device success (94.7% vs. 81.7% vs. 96.8%, p < 0.001). PVL (all degrees) frequency was likewise reduced over time (31.0% vs. 17.0% vs. 19.2%, p = 0.04). Furthermore, a trend was noticed toward shorter procedure times and shorter length of stay. However, postprocedural pacemaker implantation rates did not significantly differ (15.2% vs. 21.1% vs. 14.0%, p = 0.43).

CONCLUSION

During a 3-year period, we demonstrated better TAVR outcomes with newer SEV iterations, alongside changes in implantation techniques, which might result in better procedural and clinical outcomes. However, we did not see a significant change in peri-procedural pacemaker rates for SEV.

Coronary Artery Obstruction After Transcatheter Aortic Valve Implantation: Past, Present, and Future

Coronary obstruction (CO) is a rare but critical complication of transcatheter aortic valve implantation. It is associated with significant morbidity and mortality. This comprehensive review elucidates the evolving landscape of CO risk assessment and management strategies in the contemporary era of transcatheter aortic valve implantation. Drawing upon recent advances in computed tomography angiography, we delve into the nuanced evaluation of anatomic parameters crucial for predicting CO risk. Furthermore, this review explores the utility of interventional and surgical techniques, including chimney stenting and leaflet modification systems, in mitigating CO complications. In summary, this review serves as a practical guide for clinicians navigating the complexities of CO prevention and management in the evolving landscape of transcatheter aortic valve implantation, with the goal of optimizing patient outcomes and ensuring procedural success.

Redo-TAVR Feasibility After SAPIEN 3 Stratified by Implant Depth and Commissural Alignment: A CT Simulation Study

BACKGROUND

Redo-transcatheter aortic valve replacement (TAVR) can pin the index transcatheter heart valve leaflets open leading to sinus sequestration and restricting coronary access. The impact of initial implant depth and commissural alignment on redo-TAVR feasibility is unclear. We sought to determine the feasibility of redo-TAVR and coronary access after SAPIEN 3 (S3) TAVR stratified by implant depth and commissural alignment.

METHODS

Consecutive patients with native valve aortic stenosis were evaluated using multidetector computed tomography. S3 TAVR simulations were done at 3 implant depths, sizing per manufacturer recommendation and assuming nominal expansion in all cases. Redo-TAVR was deemed unfeasible based on valve-to-sinotubular junction distance and valve-to-sinus height <2 mm, while the neoskirt plane of the S3 transcatheter heart valve estimated coronary access feasibility.

RESULTS

Overall, 1900 patients (mean age, 80.2±8 years; STS-PROM [Society of Thoracic Surgeons Predicted Risk of Operative Mortality], 3.4%) were included. Redo-TAVR feasibility reduced significantly at shallower initial S3 implant depths (2.3% at 80:20 versus 27.5% at 100:0, P<0.001). Larger S3 sizes reduced redo-TAVR feasibility, but only in patients with a 100:0 implant (P<0.001). Commissural alignment would render redo-TAVR feasible in all patients, assuming the utilization of leaflet modification techniques to reduce the neoskirt height. Coronary access following TAV-in-TAV was affected by both index S3 implant depth and size.

CONCLUSIONS

This study highlights the critical impact of implant depth, commissural alignment, and transcatheter heart valve size in predicting redo-TAVR feasibility. These findings highlight the necessity for individualized preprocedural planning, considering both immediate results and long-term prospects for reintervention as TAVR is increasingly utilized in younger patients with aortic stenosis.

Lifetime Management of Patients With Severe Aortic Stenosis in the Era of Transcatheter Aortic Valve Replacement

Aortic stenosis is the most common valvular disease. Surgical aortic valve replacement (SAVR) using mechanical valves has been the preferred treatment for younger patients, but bioprosthetic valves are gaining favour to avoid anticoagulation with warfarin. Transcatheter aortic valve replacement (TAVR) was approved in recent years for the treatment of severe aortic stenosis in intermediate- and low-risk patients as an alternative to SAVR. The longer life expectancy of these groups of patients might exceed the durability of the TAVR or SAVR bioprosthetic valves. Therefore, many patients need 2 or even 3 interventions during their lifetime. Because it has important implications on the feasibility of subsequent procedures, the decision between opting for SAVR or TAVR as the primary procedure requires thorough consideration by the heart team, incorporating patient preferences, clinical indicators, and anatomic aspects. If TAVR is favoured initially, selecting the valve type and determining the implantation level should be conducted, aiming for positive outcomes in the index intervention and keeping in mind the potential for subsequent TAVR-in-TAVR procedures. When SAVR is selected as the primary procedure, the operator must make choices regarding the valve type and the potential need for aortic root enlargement, with the intention of facilitating future valve-in-valve interventions. This narrative review examines the existing evidence concerning the lifelong management of severe aortic stenosis, delving into available treatment strategies, particularly emphasising the initial procedure's selection and its impact on subsequent interventions.

A Case of CABG in a Patient with High Risk of Coronary Obstruction during TAV-in-TAV

A 94-year-old man who underwent transcatheter aortic valve (TAV) replacement 6 years ago was admitted because of exertional dyspnea. Transthoracic echocardiography revealed severe aortic regurgitation owing to TAV dysfunction. The patient was considered to have a high risk of occlusion of the sinus of Valsalva during TAV-in-TAV. Therefore, we performed TAV-in-TAV concomitant with coronary artery bypass grafting (CABG). The postoperative course was uneventful, and computed tomography 9 months later revealed patency of both the grafts. Concomitant CABG could be considered as one of the options in patients with a high risk of coronary occlusion during TAV-in-TAV.

Risk of Sinus Sequestration During Redo Transcatheter Aortic Valve Implantation: The Prevalence, Predictors, and Risk Stratification

The number of patients who underwent transcatheter aortic valve implantation (TAVI) with the potential for reintervention is steadily increasing; however, there is a risk of sinus sequestration (SS) during a redo TAVI. The prevalence, predictors, and risk stratification of the risk for SS remain uncertain. We analyzed computed tomography acquired from 263 patients who underwent TAVI between 2021 and 2022: balloon-expandable valve (BEV) (71%) and self-expandable valve (SEV) (29%). Patients were considered at risk for SS if they met the following: (1) BEV frame > sinotubular junction (STJ) or SEV neocommissure greater than the STJ and (2) valve-to-STJ <2 mm. The risk of left, right, and any SS in 51%, 50%, and 65%, respectively, did not differ between BEV and SEV. The predictors of any SS were the height of the left and right coronary cusp (odds ratio [OR] 0.81 and 0.71, cutoff 18.6 and 19.2 mm, respectively) and STJ minus the annulus diameter (OR 0.65, cutoff 3.7 mm) in BEV, and STJ diameter (OR 0.47, cutoff 27.6 mm) in SEV. The number of predictors stratified the risk of any SS: low risk with BEV at 0 predictors (14% at risk of SS), intermediate risk at 1 predictor (65%), high risk at 2 or 3 predictors (81% and 95%), and low risk with SEV at 0 predictors (33%) versus high risk at 1 predictor (91%). In conclusion, 2/3 of patients who underwent TAVI were at risk of SS. The height of the coronary cusp and the STJ diameter were associated with and adequately stratified the risk of SS.

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.

Parametric analysis of transcatheter aortic valve replacement in transcatheter aortic valve replacement: evaluation of coronary flow obstruction

Transcatheter aortic valve replacement (TAVR) is increasingly being considered for use in younger patients having longer life expectancy than those who were initially treated. The TAVR-in-TAVR procedure represents an appealing strategy to treat failed transcatheter heart valves (THV) likely occurring in young patients. However, the permanent displacement of first THV can potentially compromise the coronary access and ultimately inhibit the blood flow circulation. The objective of this study was to use finite-element analysis (FEA) to quantify coronary flow in a patient who underwent TAVR-in-TAVR. A parametric investigation was carried out to determine the impact of both the implantation depth and device size on coronary flow for several deployment configurations. The FEAs consisted of first delivering the SAPIEN 3 Ultra THV and then positioning the Evolut PRO device. Findings indicates that high implantation depth and device undersize of the second THV could significantly reduce coronary flow to 20% of its estimated level before TAVR. Additionally, a positive correlation was observed between coronary flow and the valve-to-coronary distance (R = 0.86 and p = 0.032 for the left coronary artery, and R = 0.93 and p = 0.014 for the right coronary artery). This study demonstrated that computational modeling can provide valuable insights to improve the pre-procedural planning of TAVR-in-TAVR.

Feasibility of redo-TAVI in self-expanding Evolut valves: a CT analysis from the Evolut Low Risk Trial substudy

BACKGROUND

Transcatheter aortic valve implantation in an existing transcatheter valve (redo-TAVI) pins the index valve leaflets in the open position (neoskirt), which can cause coronary flow compromise and limit access. Whether anatomy may preclude redo-TAVI in self-expanding Evolut valves is unknown.

AIMS

We aimed to evaluate the anatomical feasibility of redo-TAVI by simulating implantation of a balloon-expandable SAPIEN 3 (S3) within an Evolut or an Evolut within an Evolut.

METHODS

A total of 204 post-TAVI computed tomography (CT) scans from the Evolut Low Risk CT substudy were analysed. Five redo-TAVI positions were evaluated: S3-in-Evolut inflow-to-inflow, S3 outflow at Evolut nodes 4, 5, and 6, and Evolut-in-Evolut inflow-to-inflow. Univariable modelling identified pre-TAVI clinical characteristics, CT anatomical parameters, and procedural variables associated with coronary flow compromise using the neoskirt height and post-TAVI aortic root dimensions.

RESULTS

The risk of coronary flow compromise was lowest when the S3 outflow was at Evolut node 4 (20%) and highest when at Evolut node 6 (75%). The highest likelihood of preserving coronary accessibility occurred with the S3 outflow at Evolut node 4. Female sex and higher body mass index were associated with a higher risk of coronary flow compromise, as were a smaller annulus diameter, lower sinus of Valsalva height and width, shorter coronary height, smaller sinotubular junction diameter, and shallower Evolut implant depth.

CONCLUSIONS

The feasibility of redo-TAVI after Evolut failure is multifactorial and relates to the native annular anatomy, as well as the implantation depth of the index and second bioprostheses. Placement of an S3 at a lower Evolut position may reduce the risk of coronary flow compromise while preserving coronary access.

CLINICALTRIALS

gov: NCT02701283.

Redo-Transcatheter Aortic Valve Implantation Using the SAPIEN 3/Ultra Transcatheter Heart Valves-Expert Consensus on Procedural Planning and Techniques

Recent guidelines on valvular heart disease in Europe and the United States have expanded the indications for transcatheter aortic valve implantation (TAVI) to younger patients and those at lower surgical risk with severe symptomatic aortic stenosis. Consequently, the number of TAVI procedures will significantly increase worldwide. Patients with longer life expectancies will outlive their transcatheter heart valves (THVs) and require established treatment strategies for re-intervention. Current data have shown encouraging outcomes, including low mortality, with redo-TAVI; in contrast, surgical explantation of THVs is associated with high mortality. Redo-TAVI, therefore, is likely to be the treatment of choice for THV failure. The expected increase in the number of redo-TAVIs stands in contrast to the current lack of evidence on how this procedure should be planned and performed, including the risks and pitfalls operators need to consider. Preliminary reports stress the importance of preprocedural planning, understanding of THV skirt and leaflet characteristics, and implantation guidelines specific to different THVs. Currently, SAPIEN 3/Ultra is the only THV approved in Europe and the United States for redo-TAVI. Therefore, we gathered a panel of experts in TAVI procedures with the aim of providing operative guidance on redo-TAVI, using the SAPIEN 3/Ultra THV. This consensus article presents a step-by-step approach encompassing clinical, anatomical, and technical aspects in preprocedural planning, procedural techniques, and postprocedural care. In conclusion, the recommendations aim to improve the feasibility, safety, and long-term outcomes of redo-TAVI, including the durability of implanted THVs.

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.

Comparison of patients with bicuspid and tricuspid aortic valve in transcatheter aortic valve implantation

BACKGROUND

Transcatheter aortic valve implantation (TAVI) has emerged as a safe and effective alternative to surgery for aortic stenosis (AS). However, there are still differences in the procedural process and outcome of bicuspid aortic valve (BAV) treated with TAVI compared with tricuspid aortic valve.

AREAS COVERED

This review paper aims to summarize the main characteristics and clinical evidence of TAVI in patients with bicuspid and tricuspid aortic valves and compare the outcomes of TAVI procedure.

EXPERT OPINION

The use of TAVI in patients with BAV has shown similar clinical outcomes compared with tricuspid aortic valve. The efficacy of TAVI for challenging BAV anatomies remains a concern due to the lack of randomized trials. Detailed preprocedural planning is of great importance in low-surgical-risk BAV patients. A better understanding of which subtypes of BAV anatomy are at greater risk for adverse outcomes can potentially benefit the selection of TAVI or open-heart surgery in low surgical risk AS patients.

Long-term prognostic impact of paravalvular leakage on coronary artery disease requires patient-specific quantification of hemodynamics

Transcatheter aortic valve replacement (TAVR) is a frequently used minimally invasive intervention for patient with aortic stenosis across a broad risk spectrum. While coronary artery disease (CAD) is present in approximately half of TAVR candidates, correlation of post-TAVR complications such as paravalvular leakage (PVL) or misalignment with CAD are not fully understood. For this purpose, we developed a multiscale computational framework based on a patient-specific lumped-parameter algorithm and a 3-D strongly-coupled fluid-structure interaction model to quantify metrics of global circulatory function, metrics of global cardiac function and local cardiac fluid dynamics in 6 patients. Based on our findings, PVL limits the benefits of TAVR and restricts coronary perfusion due to the lack of sufficient coronary blood flow during diastole phase (e.g., maximum coronary flow rate reduced by 21.73%, 21.43% and 21.43% in the left anterior descending (LAD), left circumflex (LCX) and right coronary artery (RCA) respectively (N = 6)). Moreover, PVL may increase the LV load (e.g., LV load increased by 17.57% (N = 6)) and decrease the coronary wall shear stress (e.g., maximum wall shear stress reduced by 20.62%, 21.92%, 22.28% and 25.66% in the left main coronary artery (LMCA), left anterior descending (LAD), left circumflex (LCX) and right coronary artery (RCA) respectively (N = 6)), which could promote atherosclerosis development through loss of the physiological flow-oriented alignment of endothelial cells. This study demonstrated that a rigorously developed personalized image-based computational framework can provide vital insights into underlying mechanics of TAVR and CAD interactions and assist in treatment planning and patient risk stratification in patients.

A 20-year journey in transcatheter aortic valve implantation: Evolution to current eminence

Since the first groundbreaking procedure in 2002, transcatheter aortic valve implantation (TAVI) has revolutionized the management of aortic stenosis (AS). Through striking developments in pertinent equipment and techniques, TAVI has now become the leading therapeutic strategy for aortic valve replacement in patients with severe symptomatic AS. The procedure streamlining from routine use of conscious sedation to a single arterial access approach, the newly adapted implantation techniques, and the introduction of novel technologies such as intravascular lithotripsy and the refinement of valve-bioprosthesis devices along with the accumulating experience have resulted in a dramatic reduction of complications and have improved associated outcomes that are now considered comparable or even superior to surgical aortic valve replacement (SAVR). These advances have opened the road to the use of TAVI in younger and lower-risk patients and up-to-date data from landmark studies have now established the outstanding efficacy and safety of TAVI in patients with low-surgical risk impelling the most recent ESC guidelines to propose TAVI, as the main therapeutic strategy for patients with AS aged 75 years or older. In this article, we aim to summarize the most recent advances and the current clinical aspects involving the use of TAVI, and we also attempt to highlight impending concerns that need to be further addressed.

Long-term risk of unplanned percutaneous coronary intervention after transcatheter aortic valve replacement

BACKGROUND

Coronary access after transcatheter aortic valve replacement (TAVR) can be challenging and complicate percutaneous coronary intervention (PCI).

AIMS

We aimed to investigate the incidence, characteristics, and predictors of unplanned PCI after TAVR.

METHODS

In a single-centre registry, TAVR candidates were systematically screened for concomitant coronary artery disease (CAD) through the use of coronary angiography prior to TAVR. Rates of unplanned PCI were prospectively collected and independently adjudicated.

RESULTS

Among 3,015 patients undergoing TAVR between August 2007 and December 2020, 67 patients (2.2%) underwent unplanned PCI after TAVR. The indication for unplanned PCI was acute coronary syndrome in more than half of the cases. Patients with unplanned PCI were younger (80.2±6.5 years vs 81.9±6.4 years; p=0.028) and more likely to be male (75% vs 50%; p<0.001) than those without unplanned PCI. In a multivariable analysis, the number of diseased vessels, male sex, and younger age were independently associated with an increased risk of unplanned PCI. The cumulative incidence rates of unplanned PCI at 1, 5, and 10 years were 0.1%, 0.4%, and 0.6% in patients with no CAD at the time of TAVR, 0.7%, 2.5%, and 3.4% in patients with single-vessel disease, and 1.5%, 5.4%, and 7.4% in patients with multivessel disease, respectively.

CONCLUSIONS

The lifetime risk of unplanned PCI after TAVR is low in patients with no CAD at the time of TAVR but accumulates over time in patients with known CAD, particularly multivessel disease.

CLINICALTRIALS

gov: NCT01368250.

Lifetime Management of Aortic Stenosis: Transcatheter Versus Surgical Treatment for Young and Low-Risk Patients

Transcatheter aortic valve replacement is now indicated across all risk categories of patients with symptomatic severe aortic stenosis and has been proposed as first line option for the majority of patients >74 years old. However, median age of patients enrolled in the transcatheter aortic valve replacement low-risk trials is 74 years and transcatheter aortic valve replacement has never been systematically investigated in young low risk patients. Although the long-term data in surgical aortic valve replacement in young patients (age <75) are well known, such data remain lacking in transcatheter aortic valve replacement. In the absence of clear guideline recommendations in patients with challenging anatomies (eg, hostile calcium, bicuspid), it is important to know the potential advantages and disadvantages of each treatment and to consider how they might integrate with each other in the lifetime management of such patients. In this review, we discuss current outstanding issues on the management of severe aortic stenosis from a lifetime management perspective, particularly in terms of initial intervention and future reinterventions.

Transcatheter Aortic Valve Replacement in Failed Transcatheter Bioprosthetic Valves

Transcatheter aortic valve replacement (TAVR) is increasingly being performed in younger and lower surgical risk patients. Given the longer life expectancy of these patients, the bioprosthetic valve will eventually fail, and aortic valve reintervention may be necessary. Although currently rare, redo-TAVR will likely increase in the future as younger patients are expected to outlive their transcatheter bioprosthesis. This review provides a contemporary overview of the indications, procedural planning, implantation technique, and outcomes of TAVR in failed transcatheter bioprosthetic aortic valves.

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.

Lifetime management of patients with symptomatic severe aortic stenosis: a computed tomography simulation study

BACKGROUND

Given enough time, transcatheter heart valves (THVs) will degenerate and may require reintervention. Redo transcatheter aortic valve implantation (TAVI) is an attractive strategy but carries a risk of coronary obstruction.

AIMS

We sought to predict how many TAVIs patients could undergo in their lifetime using computed tomography (CT) simulation.

METHODS

We analysed paired CT scans (baseline and 30 days post-TAVI) from patients in the LRT trial and EPROMPT registry. We implanted virtual THVs on baseline CTs, comparing predicted valve-to-coronary (VTC) distances to 30-day CT VTC distances to evaluate the accuracy of CT simulation. We then simulated implantation of a second virtual THV within the first to estimate the risk of coronary obstruction due to sinus sequestration and the need for leaflet modification.

RESULTS

We included 213 patients with evaluable paired CTs. There was good agreement between virtual (baseline) and actual (30 days) CT measurements. CT simulation of TAVI followed by redo TAVI predicted low coronary obstruction risk in 25.4% of patients and high risk, likely necessitating leaflet modification, in 27.7%, regardless of THV type. The remaining 46.9% could undergo redo TAVI so long as the first THV was balloon-expandable but would likely require leaflet modification if the first THV was self-expanding.

CONCLUSIONS

Using cardiac CT simulation, it is possible to predict whether a patient can undergo multiple TAVI procedures in their lifetime. Those who cannot may prefer to undergo surgery first. CT simulation could provide a personalised lifetime management strategy for younger patients with symptomatic severe aortic stenosis and inform decision-making.

CLINICALTRIALS

gov: NCT02628899; ClinicalTrials.gov: NCT03557242; ClinicalTrials.gov: NCT03423459.

Coronary access after transcatheter aortic valve replacement in bicuspid versus tricuspid aortic stenosis

BACKGROUND

It is unknown whether there are differences in coronary access after transcatheter aortic valve replacement (TAVR) between bicuspid and tricuspid anatomy.

AIMS

Our aim was to investigate coronary access after TAVR using a self-expanding transcatheter heart valve (THV) in bicuspid versus tricuspid aortic valves (BAV vs TAV), based on CT simulation.

METHODS

A total of 86 type 0 BAV, 70 type 1 BAV, and 132 TAV patients were included. If the coronary ostium faced the sealed parts of the THV or the tilted-up native leaflet (NL), this was defined as THV- or NL-related challenging coronary access, respectively. If coaxial engagement was not allowed due to interference from the unwrapped frame, THV-related complex coronary access was defined.

RESULTS

The incidence of THV-related challenging coronary access was 21.2% for the left coronary artery (LCA) and 17.7% for the right coronary artery (RCA), and type 0 BAV patients encountered fewer THV-related challenging LCA access than their TAV counterparts (OR 0.42, 95% CI: 0.20-0.89). NL-related challenging coronary access was observed in 3.1% for LCA and 1.4% for RCA, and THV-related complex coronary access was identified in 5.9% for LCA and 17.0% for RCA; however, no significant differences were found among groups. The proportion of optimal fluoroscopic viewing angles suitable for guiding LCA engagement was similar among groups (64.0% vs 70.0% vs 62.1%), but those suitable for guiding RCA engagement were significantly higher in the type 0 BAV group (31.4% vs 4.3% vs 9.1%).

CONCLUSIONS

Coronary access may be challenging or complex in a significant proportion of both BAV and TAV patients after TAVR. Type 0 BAV anatomy may be more favourable for post-TAVR coronary access.

Risk of Coronary Obstruction During Redo-TAVR in Patients With Bicuspid Versus Tricuspid Aortic Valve Stenosis

OBJECTIVES

The aim of this study was to investigate the risk of coronary obstruction during redo-transcatheter aortic valve replacement (TAVR) within a previously implanted self-expanding valve in bicuspid aortic valve (BAV) versus tricuspid aortic valve (TAV) stenosis.

BACKGROUND

The prevalence of BAV in TAVR patients is expected to increase as the indication expands; however, no study has investigated the risk of coronary obstruction for future redo-TAVR in these patients.

METHODS

Computed tomography (CT) simulation analysis was performed in 86 type 0 BAV, 70 type 1 BAV, and 132 TAV patients who underwent TAVR with 1 VenusA-Valve (Venus Medtech) between January 2014 and December 2019.

RESULTS

CT-identified risk of coronary obstruction during redo-TAVR was observed in 36.1% of patients for the left coronary ostium (LCO) and 27.8% of patients for the right coronary ostium (RCO); however, the incidences were significantly lower in the type 0 BAV group than in the type 1 BAV or TAV group (for LCO: OR: 1.00 [reference] vs OR: 2.49; 95% CI: 1.24-5.01 vs OR: 2.60; 95% CI: 1.40-4.81; for RCO: OR: 1.00 [reference] vs OR: 2.14; 95% CI: 1.02-4.48 vs OR: 1.97; 95% CI: 1.02-3.80). The leaflet laceration technique may be unfeasible to improve coronary flow in 61.5% of the threatened LCOs and 58.8% of the threatened RCOs during redo-TAVR. The percentages were significantly or numerically lower in the type 0 BAV group than other groups (for LCO: 26.3% vs 62.1% vs 73.2%; P overall = 0.001; for RCO: 43.8% vs 65.2% vs 61.0%; P overall = 0.374).

CONCLUSIONS

Differences in anatomical features may impact the feasibility of future redo-TAVR. Type 0 BAV anatomy was associated with the lower incidence of CT-identified risk of coronary obstruction during redo-TAVR, and the leaflet laceration technique may be more feasible to ensure coronary flow in this population.

Coronary Artery Disease in Patients Undergoing Transvalvular Aortic Valve Implantation

Coronary artery disease (CAD) is common in patients with severe aortic stenosis. With the advent of transcatheter aortic valve implantation (TAVI) as a therapeutic option, management of CAD in such patients has undergone a revolution. Younger patients are now candidates for treatment, and have a greater life-time probability of requiring post-TAVI coronary access. Considerations include pre-procedural assessment and revascularisation, procedural planning to avoid coronary obstruction as well as optimisation of post-procedural coronary access. The authors review the challenges of managing CAD in TAVI patients, shed light on the evidence base, and provide guidance on how to optimise management.

Impact of blood pressure on coronary perfusion and valvular hemodynamics after aortic valve replacement

OBJECTIVE

Our objective was to evaluate the impact of various blood pressures (BPs) on coronary perfusion and valvular hemodynamics following aortic valve replacement (AVR).

BACKGROUND

Lower systolic and diastolic (SBP/DBP) pressures from the recommended optimal target range of SBP < 120-130 mmHg and DBP < 80 mmHg after AVR have been independently associated with increased cardiovascular and all-cause mortality.

METHODS

The hemodynamic assessment of a 26 mm SAPIEN 3 transcatheter aortic valve (TAV), 29 mm Evolut R TAV, and 25 mm Magna Ease surgical aortic valve (SAV) was performed in a pulsed left heart simulator with varying SBP, DBP, and heart rate (HR) conditions (60 and 120 bpm) at 5 L/min cardiac output (CO). Average coronary flow (CF), effective orifice areas (EOAs), and valvulo-arterial impedance (Zva) were calculated.

RESULTS

At HR of 60 bpm, at SBP < 120 mmHg and DBP < 60 mmHg, CF decreased below the physiological lower limit with several different valves. Zva and EOA were found to increase and decrease respectively with increasing SBP and DBP. The same results were found with an HR of 120 bpm. The trends of CF variation with BP were similar in all valves however the drop below the lower physiological CF limit was valve dependent.

CONCLUSION

In a controlled in vitro system, with different aortic valve prostheses in place, CF decreased below the physiologic minimum when SBP and DBP were in the range targeted by blood pressure guidelines. Combined with recent observations from patients treated with AVR, these findings underscore the need for additional studies to identify the optimal BP in patients treated with AVR for AS.

Coronary artery cannulation after transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) has revolutionised the treatment of severe, symptomatic aortic stenosis and it is now a proven and effective alternative to surgery for patients regardless of preoperative risk stratification. Nevertheless, the consequent expansion towards younger patients with longer life expectancy focuses attention on long-term considerations. In particular, although the prevalence of coronary artery disease has been shown to decrease with the lowering of estimated risk stratification, the chance of requirement of future coronary interventions after TAVI increases dramatically as a function of patients' life expectancy. To date, however, only a few studies have investigated the feasibility and reproducibility of coronary artery cannulation after TAVI. Different conditions related mainly to aortic root anatomy and specific transcatheter aortic valve (TAV) designs and deployment have been associated with impaired coronary access after TAVI. In the present review, we will examine the conditions that may make coronary access after TAVI more challenging or even impossible.

Safeguards and pitfalls for Bioprosthetic or Native Aortic Scallop Intentional Laceration to Prevent Iatrogenic Coronary Artery Obstruction during transcatheter aortic valve replacement-the BASILICA technique

Coronary artery obstruction is a devastating complication of transcatheter aortic valve replacement (TAVR). Bioprosthetic or native Aortic Scallop Intentional Laceration to prevent Iatrogenic Coronary Artery Obstruction (BASILICA) is a transcatheter, electrosurgical technique that was developed to prevent obstruction due to sinus effacement or sinus sequestration. BASILICA creates a midline laceration of one (solo) or both (doppio) offending aortic leaflets and has been performed in over 1,000 patients at high risk for obstruction. The procedure has been studied in the prospective BASILICA IDE Trial and data from the International BASILICA Registry of 214 patients supports efficacy and safety; procedural success was achieved in 94.4% and at thirty days 95.3% were free from culprit coronary artery obstruction, all-cause mortality was 2.8% and disabling stroke was reported in only 0.5%. In this review we discuss screening for patients at high risk for coronary artery obstruction, technical details related to performing the BASILICA procedure and how to troubleshoot a BASILICA procedure.

Early Leaflet Thickening, Durability and Bioprosthetic Valve Failure in TAVR

All bioprosthetic valves, both surgical and transcatheter, have a finite lifespan before their leaflets inevitably degenerate, leading to stenosis or regurgitation. As younger, low-risk patients receive a transcatheter aortic valve, it is expected that they will most likely outlive their bioprosthetic valve. The heterogeneity of studies regarding surgical valve durability makes the interpretation of the data challenging. Leaflet thickening is seen in transcatheter heart valves but currently there is no evidence that it leads to premature valve deterioration or clinical events. Standardized definitions of structural valve deterioration should allow for comparisons between future clinical trials to assess the durability of different transcatheter heart valves.

Redo-transcatheter aortic valve replacement with the supra-annular, self-expandable Evolut platform: Insights from the Transcatheter valve Therapy Registry

OBJECTIVES

To assess the safety profile of redo-TAVR procedures from patients in the transcatheter valve therapy (TVT) Registry.

BACKGROUND

The use of transcatheter aortic valves (TAV) to treat previously implanted failing TAVS (TAV-in-TAV) has been an increasingly important topic as indications for TAVR move to younger and lower-risk patients, but data on the safety and efficacy of redo-TAVR is limited.

METHODS

Patients undergoing redo-TAVR procedures using the Evolut R, Evolut PRO or Evolut PRO+ valve in the TVT Registry between April 2015 and March 2020 were included. In-hospital, 30-day and 1-year outcomes were analyzed.

RESULTS

Redo-TAVR was performed in 292 patients (213 patients received the Evolut R valve and 79 received the Evolut PRO or PRO+ valve). Device success was achieved in 94.5%. In-hospital mortality was 2.1%, stroke occurred in 2.7%, and 77.2% of patients were discharged home. There were no cases of coronary compression/obstruction or myocardial infarction that occurred in index hospitalization. Mean gradient at 30-days was 11.9 ± 6.9 mmHg, and 73.1% had none/trace total aortic regurgitation.

CONCLUSIONS

Results from the TVT Registry demonstrate good short-term outcomes after redo-TAVR with the supra-annular, self-expandable Evolut platform. Long-term follow-up is necessary to further expand understanding this complex scenario.

Coronary access after TAVR with a cylindrical shaped valve: Learning from LOTUS

BACKGROUND/PURPOSE

Data on the feasibility of coronary access (CA) through above or outside of the cylindrical shaped-transcatheter heart valve (THV) are very limited. The aims of the present study were to assess the feasibility of CA after transcatheter aortic valve replacement (TAVR) with the LOTUS using multi detector computed tomography (MDCT) and the reliability of algorithm detecting unfavorable CA.

METHODS/MATERIALS

Post-TAVR MDCT of 41 patients with 82 coronary arteries were evaluated. The relationship and distance between the THV flame and sinotubular junction (STJ) and coronary ostia were assessed. Unfavorable CA was defined as the valve-to-STJ distance < 2-mm or the valve-to-coronary ostia distance < 2-mm if the THV flame was above STJ or coronary ostia.

RESULTS

MDCT-identified unfavorable CA was observed in 29.3% for the left coronary artery and 41.5% for the right coronary artery. In total, 53.7% of patients had at least one unfavorable CA and 14.6% of those had unfavorable CA for both left and right coronary artery. While patients underwent coronary angiography after TAVR, the success rates of selective coronary cannulation were significantly lower in patients with MDCT-identified unfavorable CA in comparison to those with favorable CA for left (20.0% vs. 100%, P = 0.002) and right coronary artery (0% vs. 100%, P < 0.001).

CONCLUSIONS

Future CA through above or outside of a cylindrical shaped THV may be challenging with a significant probability. Our algorithm identifying unfavorable CA using post-MDCT seems to be useful for estimating the risk of unsuccessful selective cannulation.

COVID-19 and pulmonary fibrosis: therapeutics in clinical trials, repurposing, and potential development

In 2019, an unprecedented disease named coronavirus disease 2019 (COVID-19) emerged and spread across the globe. Although the rapid transmission of COVID-19 has resulted in thousands of deaths and severe lung damage, conclusive treatment is not available. However, three COVID-19 vaccines have been authorized, and two more will be approved soon, according to a World Health Organization report on December 12, 2020. Many COVID-19 patients show symptoms of acute lung injury that eventually leads to pulmonary fibrosis. Our aim in this article is to present the relationship between pulmonary fibrosis and COVID-19, with a focus on angiotensin converting enzyme-2. We also evaluate the radiological imaging methods computed tomography (CT) and chest X-ray (CXR) for visualization of patient lung condition. Moreover, we review possible therapeutics for COVID-19 using four categories: treatments related and unrelated to lung disease and treatments that have and have not entered clinical trials. Although many treatments have started clinical trials, they have some drawbacks, such as short-term and small-group testing, that need to be addressed as soon as possible.

Advances in Transcatheter Electrosurgery for Treating Valvular Heart Disease

Delivery of electrosurgery energy through catheters and guidewires enables interventionists to 'cut' through obstructive intravascular lesions or across cardiac chambers. A novel application of transcatheter electrosurgery is to make controlled lacerations in heart valve leaflets. This review describes three applications of transcatheter electrosurgery of aortic and mitral valve leaflets to enable transcatheter heart valve implantation. Intentional laceration of the anterior mitral leaflet to prevent left ventricular outflow obstruction splits and splays the anterior mitral valve and enables transcatheter mitral valve replacement without left ventricular outflow tract obstruction. Technique modifications and novel applications are described. Bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction enables transcatheter aortic valve replacement without coronary artery obstruction. The technique is described and novel uses, especially in the setting of repeat transcatheter aortic valve replacement, are discussed. Finally, electrosurgical laceration and stabilization of mitral valve clip devices (ELASTA-Clip) enables transcatheter mitral valve replacement after MitraClip implantation. In conclusion, transcatheter electrosurgery is an important and versatile new tool in structural heart intervention.