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

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.

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.

TAVR in TAVR: Where Are We in 2023 for Management of Failed TAVR Valves?

PURPOSE OF REVIEW

As TAVR is increasingly performed on younger patients with a longer life expectancy, the number of redo-TAVR procedures is likely to increase in the coming years. Limited data is currently available on this sometimes challenging procedure. We provide a summary of currently published literature on management of patients with a failed transcatheter aortic valve.

RECENT FINDINGS

Recent registry data have increased the clinical knowledge on redo-TAVR. Additionally, numerous bench studies have provided valuable insights into the technical aspects of redo-TAVR with various combinations of valve types. Redo-TAVR can be performed safely in selected cases with a high procedural success and good short-term outcomes. However, at present, the procedure remains relatively infrequent and many patients are not eligible. Bench testing can be useful to understand important concepts such as valve expansion, neoskirt, leaflet overhang, and leaflet deflection as well as their potential clinical implications.

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.

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.

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.

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.

Transcatheter heart valve commissural alignment: an updated review

Transcatheter aortic valve replacement (TAVR) indications recently extended to lower surgical risk patients with longer life expectancy. Commissural alignment (CA) is one of the emerging concepts and is becoming one of the cornerstones of the TAVR procedure in a patient with increased longevity. Indeed, CA may improve transcatheter heart valve (THV) hemodynamics, future coronary access, and repeatability. The definition of CA has been recently standardized by the ALIGN-TAVR consortium using a four-tier scale based on CT analysis. Progress has been made during the index TAVR procedure to optimize CA, especially with self-expandable platforms. Indeed, specific delivery catheter orientation, THV rotation, and computed-tomography-derived views have been proposed to achieve a reasonable degree of CA. Recent data demonstrate feasibility, safety, and a significant reduction in coronary overlap using these techniques, especially with self-expandable platforms. This review provides an overview of THV CA including assessment methods, alignment techniques during the index TAVR procedure with different THV platforms, the clinical impact of commissural misalignment, and challenging situations for CA.

Quantification of Commissural Alignment of Balloon-Expandable THV on Fluoroscopy: A Comparison Study With Post-TAVR CT

BACKGROUND

Coronary access may be challenging following transcatheter aortic valve replacement (TAVR) in the setting of transcatheter heart valve (THV) commissural misalignment.

OBJECTIVES

The authors aimed to quantify the degree of commissural alignment following balloon-expandable THV implantation using a fluoroscopy-based trigonometric approach and assess its correlation with post-TAVR computed tomography (CT).

METHODS

Twenty patients who had undergone both TAVR with the balloon-expandable SAPIEN 3 THV and post-TAVR CT were included in the analysis. Optimized, predeployment 3-cusp angiographic view and postdeployment angiographic view using identical fluoroscopic projections were required. The distance between the most central posterior commissural strut and the THV centerline was assessed. Commissural alignment was calculated by means of a trigonometrical approach using an arcsine function, assuming circular deployment of the THV. Commissural alignment was stratified using a 4-tier scale: aligned (0° to 15°); mildly misaligned (15° to 30°); moderately misaligned (30° to 45°), and severely misaligned (45° to 60°).

RESULTS

Seven patients (35.0%) were misclassified by 1 tier, and no patient was misclassified by 2 or more tiers, with strong agreement between CT and fluoroscopy (weighted Cohen's kappa coefficient = 0.724). Correlation of the commissural offset angle determined from fluoroscopy and CT was excellent (r = 0.986; 95% CI: 0.965 to 0.995). Bland-Altman analysis demonstrated a strong agreement between both modalities with a mean difference of 0.5° (95% limits of agreement: -12.7° to 13.7°).

CONCLUSIONS

The degree of commissural alignment of the balloon-expandable THV can be reliably assessed and quantified on postdeployment fluoroscopy using a standardized 3-cusp view and trigonometry-based analysis.

Personalised Treatment in Aortic Stenosis: A Patient-Tailored Transcatheter Aortic Valve Implantation Approach

Transcatheter aortic valve replacement (TAVI) has become a game changer in the management of severe aortic stenosis shifting the concept from inoperable or high-risk patients to intermediate or low surgical-risk individuals. Among devices available nowadays, there is no clear evidence that one device is better than the other or that one device is suitable for all patients. The selection of the optimal TAVI valve for every patient represents a challenging process for clinicians, given a large number of currently available devices. Consequently, understanding the advantages and disadvantages of each valve and personalising the valve selection based on patient-specific clinical and anatomical characteristics is paramount. This review article aims to both analyse the available devices in the presence of specific clinical and anatomic features and offer guidance to select the most suitable valve for a given patient.

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.