Bicuspid aortic valve sizing for transcatheter aortic valve implantation: Development and validation of an algorithm based on multi-slice computed tomography

Comparison of downsizing strategy (HANGZHOU Solution) and standard annulus sizing strategy in type 0 bicuspid aortic stenosis patients undergoing transcatheter aortic valve replacement: Rationale and design of a randomized clinical trial

BACKGROUND

There has not been a consensus on the prothesis sizing strategy in type 0 bicuspid aortic stenosis (AS) patients undergoing transcatheter aortic valve replacement (TAVR). Modifications to standard annular sizing strategies might be required due to the distinct anatomical characteristics. We have devised a downsizing strategy for TAVR using a self-expanding valve specifically for patients with type 0 bicuspid AS. The primary aim of this study is to compare the safety and efficacy of downsizing strategy with the Standard Annulus Sizing Strategy in TAVR for patients with type 0 bicuspid AS.

TRIAL DESIGN

It is a prospective, multi-center, superiority, single-blinded, randomized controlled trial comparing the Down Sizing and Standard Annulus Sizing Strategy in patients with type 0 bicuspid aortic stenosis undergoing transcatheter aortic valve replacement. Eligible participants will include patients with severe type 0 bicuspid AS, as defined by criteria such as mean gradient across aortic valve ≥40 mmHg, peak aortic jet velocity ≥4.0 m/s, aortic valve area (AVA) ≤1.0 cm², or AVA index ≤0.6 cm2/m2. These patients will be randomly assigned, in a 1:1 ratio, to either the Down Sizing Strategy group or the Standard Sizing Strategy group. In the Down Sizing Strategy group, a valve one size smaller will be implanted if the "waist sign" manifests along with less than mild regurgitation during balloon pre-dilatation. The primary end point of the study is a composite of VARC-3 defined device success, absence of both permanent pacemaker implantation due to high-degree atrioventricular block and new-onset complete left bundle branch block.

CONCLUSION

This study will compare the safety and efficacy of Down Sizing Strategy with the Standard Annulus Sizing Strategy and provide valuable insights into the optimal approach for sizing in TAVR patients with type 0 bicuspid AS. We hypothesize that the Down Sizing Strategy will demonstrate superiority when compared to the Standard Annulus Sizing Strategy. (Down Sizing Strategy (HANGZHOU Solution) vs Standard Sizing Strategy TAVR in Bicuspid Aortic Stenosis (Type 0) (TAILOR-TAVR), NCT05511792).

Single-Center Experience with the Balloon-Expandable Myval Transcatheter Aortic Valve System in Patients with Bicuspid Anatomy: Procedural and 30-Day Follow-Up

Aims: To report our single-center data regarding the initial 52 consecutive patients with a bicuspid aortic valve who underwent a Transcatheter Aortic Valve Implantation (TAVI) procedure using the new balloon-expandable MYVAL system. The focus is on reporting procedural details and outcomes over the 30-day postoperative period. Methods: From December 2019 to July 2023, 52 consecutive patients underwent a TAVI procedure with bicuspid anatomy. All patients had moderate to-high surgical risk or were unsuitable for surgical aortic valve replacement based on the Heart Team's decision. Outcomes were analyzed according to the VARC-2 criteria. The results of bicuspid patients were compared to patients with tricuspid anatomy in the overall study group, and further analysis involved a comparison between 52 pairs after propensity score matching. The device performance was evaluated using transthoracic echocardiography. Data collection was allowed by the Local Ethical Committee. Results: The mean age was 71 ± 7.1 years, and 65.4% were male. The mean Euroscore II and STS score were 3.3 ± 3.2 and 5.2 ± 3.3, respectively. Baseline characteristics and echocardiographic parameters were well balanced even in the unmatched comparison. Procedures were significantly longer in the bicuspid group and resulted in a significantly higher ARI index. All relevant anatomic dimensions based on the CT scans were significantly higher in bicuspid anatomy, including a higher implantation angulation, a higher rate of horizontal aorta and a higher proportion of patients with aortopathy. In the unmatched bicuspid vs. tricuspid comparison, postprocedural outcomes were as follows: in-hospital mortality 0% vs. 1.4% (p = 0.394), device success 100% vs. 99.1% (p = 0.487), TIA 1.9% vs. 0% (p = 0.041), stroke 1.9% vs. 0.9% (p = 0.537), major vascular complication 3.8% vs. 2.3% (p = 0.530), permanent pacemaker implantation 34% vs. 30.4% (p = 0.429), and cardiac tamponade 0% vs. 0.5% (p = 0.624). In the propensity-matched bicuspid vs. tricuspid comparison, postprocedural outcomes were as follows: in-hospital mortality 0% vs. 0%, device success 100% vs. 100%, TIA 1.9% vs. 0% (p = 0.315), stroke 1.9% vs. 0.9% (p = 0.315), major vascular complication 3.8% vs. 0% (p = 0.475), permanent pacemaker implantation 34% vs. 24% (p = 0.274), and cardiac tamponade 0% vs. 0%. There was no annular rupture nor need for second valve or severe aortic regurgitation in both the unmatched and matched comparison. The peak and mean aortic gradients did not differ at discharge and at 30-day follow-up between the two groups regardless of whether the comparison was unmatched or matched. There were no paravalvular leakages (moderate or above) in the bicuspid patients. Intermediate and extra sizes of the Myval THV system used a significantly higher proportion in bicuspid anatomy with a significantly higher oversize percentage in tricuspid anatomy. Conclusions: The TAVI procedure using the Myval THV system in patients with significant aortic stenosis and bicuspid aortic valve anatomy is safe and effective. Hemodynamic parameters do not differ between tricuspid and bicuspid patients. However, the permanent pacemaker implantation rate is higher than expected; its relevance on long-term survival is controversial.

An Overview of Diabetic Cardiomyopathy

Diabetic cardiomyopathy (DCM) is a myocardial disorder that is characterised by structural and functional abnormalities of the heart muscle in the absence of hypertension, valvular heart disease, congenital heart defects, or coronary artery disease (CAD). After witnessing a particular form of cardiomyopathy in diabetic individuals, Rubler et al. came up with the moniker diabetic cardiomyopathy in 1972. Four stages of DCM are documented, and the American College of Cardiology/American Heart Association Stage and New York Heart Association Class for HF have some overlap. Diabetes is linked to several distinct forms of heart failure. Around 40% of people with heart failure with preserved ejection fraction (HFpEF) have diabetes, which is thought to be closely associated with the pathophysiology of HFpEF. Diabetes and HF are uniquely associated in a bidirectional manner. When compared to the general population without diabetes, those with diabetes have a risk of heart failure that is up to four times higher. A biomarker is a trait that is reliably measured and assessed as a predictor of healthy biological activities, pathological processes, or pharmacologic responses to a clinical treatment. Several biomarker values have been discovered to be greater in patients with diabetes than in control subjects among those who have recently developed heart failure. Myocardial fibrosis and hypertrophy are the primary characteristics of DCM, and structural alterations in the diabetic myocardium are often examined by non-invasive, reliable, and reproducible procedures. An invasive method called endomyocardial biopsy (EMB) is most often used to diagnose many cardiac illnesses.

Transcatheter Aortic Valve Implantation for Bicuspid Aortic Valve Disease: Procedural Planning and Clinical Outcomes

Bicuspid aortic valve (BAV) is the most common congenital heart disease, with a prevalence of 1-2% and occurring in >20% of octogenarians referred for aortic valve replacement. However, BAV patients have been systematically excluded from pivotal randomized trials. Since TAVI indications are moving toward low-risk patients, an increase in the number of BAV patients who undergo TAVI is expected. BAV represents a challenge due to its unique morphological features (raphe, extreme asymmetrical valve calcifications, cusp asymmetry and aortopathy) and the lack of consensus about the accurate sizing method. The role of multi-slice computed tomography (MSCT) in the planification of the TAVI procedure is well-established, being useful to define the optimal valve sizing and the implantation strategy. New-generation devices, more experience of the operators and better planification of the procedure have been associated with similar clinical outcomes in bicuspid and tricuspid patients undergoing TAVI.

ACR Appropriateness Criteria® Preprocedural Planning for Transcatheter Aortic Valve Replacement: 2023 Update

This document discusses preprocedural planning for transcatheter aortic valve replacement, evaluating the imaging modalities used in initial imaging for preprocedure planning under two variants 1) Preintervention planning for transcatheter aortic valve replacement: assessment of aortic root; and 2) Preintervention planning for transcatheter aortic valve replacement: assessment of supravalvular aorta and vascular access. US echocardiography transesophageal, MRI heart function and morphology without and with IV contrast, MRI heart function and morphology without IV contrast and CT heart function and morphology with IV contrast are usually appropriate for assessment of aortic root. CTA chest with IV contrast, CTA abdomen and pelvis with IV contrast, CTA chest abdomen pelvis with IV contrast are usually appropriate for assessment of supravalvular aorta and vascular access. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Multimodality imaging for patient selection, procedural guidance, and follow-up of transcatheter interventions for structural heart disease: a consensus document of the EACVI Task Force on Interventional Cardiovascular Imaging: part 1: access routes, transcatheter aortic valve implantation, and transcatheter mitral valve interventions

Transcatheter therapies for the treatment of structural heart diseases (SHD) have expanded dramatically over the last years, thanks to the developments and improvements of devices and imaging techniques, along with the increasing expertise of operators. Imaging, in particular echocardiography, is pivotal during patient selection, procedural monitoring, and follow-up. The imaging assessment of patients undergoing transcatheter interventions places demands on imagers that differ from those of the routine evaluation of patients with SHD, and there is a need for specific expertise for those working in the cath lab. In the context of the current rapid developments and growing use of SHD therapies, this document intends to update the previous consensus document and address new advancements in interventional imaging for access routes and treatment of patients with aortic stenosis and regurgitation, and mitral stenosis and regurgitation.

Transcatheter Aortic Valve Replacement for Bicuspid Aortic Stenosis With a Severely Calcified Raphe Using An Under-Sized SAPIEN 3 Valve: Sizing by the Circle Method and Deployment by the Pressure-Regulated Method

Transcatheter aortic valve replacement (TAVR) for bicuspid aortic valve stenosis is challenging, and the absence of established methods for sizing the bicuspid aortic valve (BAV) complicates TAVR. We report a case of successful TAVR for bicuspid aortic stenosis with a severely calcified raphe. We used an undersized SAPIEN 3 valve, with three safety measures based on assessment of structural characteristics, sizing by the circle method, and deployment of the valve by the pressure-regulated method.

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.

Ongoing experience with patient-specific computer simulation of transcatheter aortic valve replacement in bicuspid aortic valve

BACKGROUND

Transcatheter aortic valve replacement (TAVR) is increasingly being used to treat younger, lower-risk patients with bicuspid aortic valve (BAV). Patient-specific computer simulation may identify patients at risk for developing paravalvular regurgitation (PVR) and major conduction disturbance. Only limited prospective experience of this technology exist. We wished to describe our ongoing experience with patient-specific computer simulation.

METHODS

Patients who were referred for consideration of TAVR with a self-expanding transcatheter heart valve (THV) and had BAV identified on pre-procedural cardiac computed tomography imaging underwent patient-specific computer simulation. The computer simulations were reviewed by the Heart Team and used to guide surgical or transcatheter treatment approaches and to aid in THV sizing and positioning. Clinical outcomes were recorded.

RESULTS

Between May 2019 and May 2021, 16 patients with BAV were referred for consideration of TAVR with a self-expanding THV. Sievers Type 1 morphology was present in 15 patients and Type 0 in the remaining patient. Two patients were predicted to develop moderate-to-severe PVR with a TAVR procedure and these patients underwent successful surgical aortic valve replacement. In the remaining 14 patients, computer simulation was used to optimize THV sizing and positioning to minimise PVR and conduction disturbance. One patient with a low valve implantation depth developed moderate PVR and this complication was correctly predicted by the computer simulations. No patient required insertion of a new permanent pacemaker.

CONCLUSION

Patient-specific computer simulation may be used to guide the most appropriate treatment modality for patients with BAV. The usage of computer simulation to guide THV sizing and positioning was associated with favourable clinical outcomes.

Transcatheter aortic valve implantation in patients with bicuspid valve morphology: a roadmap towards standardization

Indications for transcatheter aortic valve implantation (TAVI) have expanded in many countries to include patients with aortic stenosis who are at low surgical risk, and a similar expansion to this cohort is anticipated elsewhere in the world, together with an increase in the proportion of patients with bicuspid aortic valve (BAV) morphology as the age of the patients being treated decreases. To date, patients with BAV have been excluded from major randomized trials of TAVI owing to anatomical considerations. As a consequence, BAV has been a relative contraindication to the use of TAVI in international guidelines. Although clinical experience and observational data are accumulating, BAV presents numerous anatomical challenges for successful TAVI, despite advances in device design. Furthermore, in those with BAV, substantial geographical variation exists in patient characteristics, clinical approach and procedural strategy. Therefore, in this Roadmap article, we summarize the existing evidence and provide consensus recommendations from an international group of experts on the application of TAVI in patients with BAV in advance of the anticipated growth in the use of this procedure in this challenging cohort of 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.

Bioprosthetic valve dysfunction and failure after TAVI in bicuspid aortic valve stenosis during one-year follow-up according to VARC-3

BACKGROUND

Transcatheter aortic valve implantation (TAVI) in bicuspid aortic valve (BAV) stenosis has become more frequent in the last years. This may pose challenges for long-time valve durability. Therefore, we aimed to evaluate the prevalence of bioprosthetic valve dysfunction (BVD) with the newest-generation devices in BAV stenosis up to one-year follow-up (FU).

METHODS

The primary endpoint was defined as the prevalence of BVD during the first procedural year according to Valve Academic Research Consortium (VARC)-3 criteria. Secondary endpoints were defined as failure in device success and clinical endpoints according to VARC-3.

RESULTS

A total of 107 patients were included. Of these, 34 subjects (31.8%) met the criteria for BVD during a mean FU of 263 ± 180 days, of which 20.2% were already documented after thirty days. Device success after one year was lower in the + BVD cohort (57.6% vs. 98.7%, p < 0.0001*). The rates of structural valve deterioration were 6.5%, non-structural valve deterioration (NSVD) 17.8%, subclinical leaflet thickening 10.3%, and endocarditis 0.9%. NSVD was foremost triggered by patient prosthesis mismatch in balloon-expandable valves. Hemodynamic valve deterioration stage 1 and 2 was confirmed in 16.8% of + BVD patients, while stage 1 and 3 bioprosthetic valve failure occurred in 1.9%. There was no impact of BVD on mortality.

CONCLUSION

There is critical evidence of early BVD after TAVI in BAV during one-year FU in one-third of patients, also lowering device success. The most frequently observed bioprosthetic valve dysfunction was NSVD due to patient prosthesis mismatch following TAVI with a balloon-expandable valve.

Long-Term Mortality After TAVI for Bicuspid vs. Tricuspid Aortic Stenosis: A Propensity-Matched Multicentre Cohort Study

Objectives

Patients with bicuspid aortic valve (BAV) stenosis were excluded from the pivotal trials of transcatheter aortic valve implantation (TAVI). We compared the in-hospital and long-term outcomes between patients undergoing TAVI for bicuspid and tricuspid aortic valve (TAV) stenosis.

Methods

We performed a retrospective registry-based analysis on patients who underwent TAVI for BAV and TAV at five different centers between January 2009 and August 2017. The primary outcome was long-term all-cause mortality. Secondary outcomes were in-hospital mortality, procedural complications, and valve performance.

Results

Of 1,451 consecutive patients who underwent TAVI, two propensity-matched cohorts consisting of 130 patients with BAV and 390 patients with TAV were analyzed. All-cause mortality was comparable in both groups up to 10 years following TAVI (HR 1.09, 95% CI: 0.77–1.51). Device success and in-hospital mortality were comparable between the groups (96 vs. 95%, p = 0.554 and 2.3 vs. 2.1%, p = 0.863, respectively). Incidence of procedural complications was similar in both groups, with a trend toward a higher rate of stroke in patients with BAV (5 vs. 2%, p = 0.078). Incidence of moderate or severe paravalvular leak (PVL) at discharge was comparable in both groups (2 vs. 2%, p = 0.846). Among patients with BAV, all-cause mortality was similar in self-expanding and balloon-expandable prostheses (HR 1.02, 95% CI: 0.52–1.99) and lower in new-generation devices compared to old-generation valves (HR 0.27, 95% CI 0.12–0.62).

Conclusion

Patients who had undergone TAVI for BAV had comparable mortality to patients with TAV up to 10 years after the procedure. The device success, in-hospital mortality, procedural complications, and PVL rate were comparable between the groups. The high rate of neurological complications (5%) in patients with BAV warrants further investigation.

Update on supra-annular sizing of transcatheter aortic valve prostheses in raphe-type bicuspid aortic valve disease according to the LIRA method

Recent evidence has shown that transcatheter heart valve (THV) anchoring in bicuspid aortic valve (BAV) patients occurs at the level of the raphe, known as the LIRA (Level of Implantation at the RAphe) plane. Our previous work in a cohort of 20 patients has shown that the delineation of the perimeter and device sizing at this level is associated with optimal procedural outcome. The goals of this study were to confirm the feasibility of this method, evaluate 30-day outcomes of LIRA sizing in a larger cohort of patients, assess interobserver variation and reproducibility of this sizing methodology, and analyse the interaction of LIRA-sized prostheses with the surrounding anatomy. The LIRA sizing method was applied to consecutive patients presenting to our centre with raphe-type BAV disease between November 2018 and October 2021. Supra-annular self-expanding THVs were sized based on baseline CT scan perimeters at the LIRA plane and the virtual basal ring. In cases where there was discrepancy between the two measurements, the plane with the smallest perimeter was considered the reference for prosthesis sizing. Post-procedural device success, defined according to Valve Academic Research Consortium-2 (VARC-2) criteria, was evaluated in the overall cohort. A total of 50 patients (mean age 80 ± 6 years, 70% male) with raphe-type BAV disease underwent transcatheter aortic valve replacement (TAVR) using different THV prostheses. The LIRA plane method appeared to be highly successful (100% VARC-2 device success) with no procedural mortality, no valve migration, no moderate-severe paravalvular leak, and low transprosthetic gradients (residual mean gradient 8.2 ± 3.4 mmHg). There were no strokes, no in-hospital or 30-day mortality, and an incidence of in-hospital pacemaker implantation of 10%. Furthermore, measurement of the LIRA plane perimeter was highly reproducible between observers (r = 0.980; P < 0.001) and predictive of the post-procedural prosthetic valve perimeter on CT scanning (r = 0.981; P < 0.001). We confirm the feasibility of supra-annular sizing using the LIRA method in a large cohort of patients with high procedural success and good clinical outcomes at 30 days. Application of the LIRA method optimizes THV prosthesis sizing in patients with raphe-type BAV disease.

The Presence of Calcified Raphe Is an Independent Predictor of Adverse Long-Term Clinical Outcomes in Patients With Bicuspid Aortic Stenosis Undergoing Transcatheter Aortic Valve Replacement

Objective

Current guidelines recommend that transcatheter aortic valve replacement (TAVR) for bicuspid aortic valve (BAV) with aortic stenosis (AS) should only be performed in selected patients. However, we consider it even more crucial to identify what the really important factors are while determining long-term outcomes in patients with BAV undergoing TAVR, which is precisely the aim of this study.

Methods

We retrospectively evaluated consecutive patients who underwent TAVR with balloon-expandable Sapien XT or Sapien 3 valves (Edwards Lifesciences, Irvine, CA) for the treatment of severe bicuspid AS. The primary end points were major adverse cardiac and cerebral events (MACCE), that is, mortality, non-fatal myocardial infarction (MI), disabling stroke, valve failure needing reintervention, or clinically relevant valve thrombosis during follow-up.

Results

A total of 56 patients who underwent TAVR with Sapien XT (n = 20) or Sapien 3 (n = 36) were included. The device and procedural success rates were similar between the two TAVR valves; however, the newer-generation Sapien 3 yielded a trend toward better long-term clinical outcomes than the early-generation Sapien XT did (MACCE rates 35 vs. 11%, p = 0.071). In the multivariate Cox proportional hazards analyses, the presence of calcified raphe > 4 mm was the only independent predictor of long-term MACCE (hazard ratio: 6.76; 95% confidence interval: 1.21–37.67, p = 0.029).

Conclusion

TAVR performed by a skilled heart team, while using newer-generation balloon-expandable Sapien 3 valve, may yield better long-term clinical outcomes compared to TAVR using early-generation Sapien XT valve. Moreover, the presence of calcified raphe >4 mm is an independent determinant of adverse clinical outcomes.

Bicuspid Aortic Valve Stenosis: From Pathophysiological Mechanism, Imaging Diagnosis, to Clinical Treatment Methods

Bicuspid aortic valve (BAV) is the most frequent congenital anomaly and has a natural evolution toward aortic regurgitation or stenosis due to the asymmetrical valve function associated with an evolutive ascending aortopathy. Several BAV classifications exist describing the presence and number of raphe, amount and location of calcium, and the symmetry of the functional cusps. The impact of BAV morphology on transcatheter aortic valve implantation (TAVI) outcomes still remains little investigated. Pivotal randomized trials comparing TAVI with surgery have excluded BAV until yet. However, data from registries and observational studies including highly selected patients have shown promising results of TAVI in BAV. With this review, we aimed at describing anatomical and pathophysiological characteristics of BAV, discussing the main aspects to assess diagnostic imaging modalities, and giving an overview of TAVI outcomes and technical considerations specific to BAV morphology.

Bicuspid Valve Sizing for Transcatheter Aortic Valve Implantation: The Missing Link

Transcatheter aortic valve implantation (TAVI) is a well-recognized and established therapy for severe aortic stenosis, with expanding indications toward younger patients with low surgical risk profile. As bicuspid aortic valve (BAV) affects ~1-2% of the population, it may be speculated that an increasing number of patients with degenerated BAV may eventually need TAVI during the course of the disease. On the other hand, BAV represents a challenge due to its peculiar anatomical features and the lack of consensus on the optimal sizing strategy. The aim of this paper is to review the peculiar aspects of BAV and to discuss and compare the currently available sizing methods. Special attention is given to the role of pre-procedural imaging, mostly with multislice computed tomography, and to the aspects that operators should evaluate in order to ensure an optimal procedural planning and avoid procedural-related complications.

Safety and Efficacy of Myval Implantation in Patients with Severe Bicuspid Aortic Valve Stenosis-A Multicenter Real-World Experience

Bicuspid aortic valve (BAV) is the most common valvular congenital anomaly and is apparent in nearly 50% of candidates for AV replacement. While transcatheter aortic valve implantation (TAVI) is a recommended treatment for patients with symptomatic severe aortic stenosis (AS) at all surgical risk levels, experience with TAVI in severe bicuspid AS is limited. TAVI in BAV is still a challenge due to its association with multiple and complex anatomical considerations. A retrospective study has been conducted to investigate TAVI's procedural and 30-day outcomes using the Myval transcatheter heart valve (THV) (Meril Life Sciences Pvt. Ltd. Vapi, Gujarat, India) in patients with severe bicuspid AS. Data were collected on 68 patients with severe bicuspid AS who underwent TAVI with the Myval THV. Baseline characteristics, procedural, 30-day echocardiographic and clinical outcomes were collected. The mean age and STS PROM score were 72.6 ± 9.4 and 3.54 ± 2.1. Procedures were performed via the transfemoral route in 98.5%. Major vascular complications (1.5%) and life-threatening bleeding (1.5%) occurred infrequently. No patient had coronary obstruction, second valve implantation or conversion to surgery. On 30-day echocardiography, the mean transvalvular gradient and effective orifice area were 9.8 ± 4.5 mmHg and 1.8 ± 0.4 cm², respectively. None/trace aortic regurgitation occurred in 76.5%, mild AR in 20.5% and moderate AR in 3%. The permanent pacemaker implantation rate was 8.5% and 30-day all-cause death occurred in 3.0% of cases. TAVI with the Myval THV in selected BAV anatomy is associated with favorable short-term hemodynamic and clinical outcomes.

The Predictors of Conduction Disturbances Following Transcatheter Aortic Valve Replacement in Patients With Bicuspid Aortic Valve: A Multicenter Study

Objective: To evaluate the predictors of new-onset conduction disturbances in bicuspid aortic valve patients using self-expanding valve and identify modifiable technical factors. Background: New-onset conduction disturbances (NOCDs), including complete left bundle branch block and high-grade atrioventricular block, remain the most common complication after transcatheter aortic valve replacement (TAVR). Methods: A total of 209 consecutive bicuspid patients who underwent self-expanding TAVR in 5 centers in China were enrolled from February 2016 to September 2020. The optimal cut-offs in this study were generated from receiver operator characteristic curve analyses. The infra-annular and coronal membranous septum (MS) length was measured in preoperative computed tomography. MSID was calculated by subtracting implantation depth measure on postoperative computed tomography from infra-annular MS or coronal MS length. Results: Forty-two (20.1%) patients developed complete left bundle branch block and 21 (10.0%) patients developed high-grade atrioventricular block after TAVR, while 61 (29.2%) patients developed NOCDs. Coronal MS <4.9 mm (OR: 3.08, 95% CI: 1.63-5.82, p = 0.001) or infra-annular MS <3.7 mm (OR: 2.18, 95% CI: 1.04-4.56, p = 0.038) and left ventricular outflow tract perimeter <66.8 mm (OR: 4.95 95% CI: 1.59-15.45, p = 0.006) were powerful predictors of NOCDs. The multivariate model including age >73 years (OR: 2.26, 95% CI: 1.17-4.36, p = 0.015), Δcoronal MSID <1.8 mm (OR: 7.87, 95% CI: 2.84-21.77, p < 0.001) and prosthesis oversizing ratio on left ventricular outflow tract >3.2% (OR: 3.42, 95% CI: 1.74-6.72, p < 0.001) showed best predictive value of NOCDs, with c-statistic = 0.768 (95% CI: 0.699-0.837, p < 0.001). The incidence of NOCDs was much lower (7.5 vs. 55.2%, p < 0.001) in patients without Δcoronal MSID <1.8 mm and prosthesis oversizing ratio on left ventricular outflow tract >3.2% compared with patients who had these two risk factors. Conclusion: The risk of NOCDs in bicuspid aortic stenosis patients could be evaluated based on MS length and prosthesis oversizing ratio. Implantation depth guided by MS length and reducing the oversizing ratio might be a feasible strategy for heavily calcified bicuspid patients with short MS.

Ten-year experience with transcatheter aortic valve implantation in bicuspid aortic valve: lessons learned and future perspectives

Bicuspid aortic valve (BAV) stenosis has traditionally been perceived as a contraindication to transcatheter aortic valve implantation (TAVI) due to its specific anatomical characteristics including extensive calcifications, high leaflet coaptation and frequently encountered aortic root dilation, which may result in worse procedural outcomes and higher risk of complications. Hence, BAV patients were not included in previous clinical trials. In the recent years, improved pre-procedural imaging and technological advances have gradually enabled expansion of TAVI to patients with complex anatomy, including those with BAV. Moreover, indications for TAVI are expanding to a younger group of patients with fewer comorbidities, and BAV is more prevalent in this population. Contemporary multicenter registry-based studies indicate that patients undergoing TAVI for BAV have similar outcomes as those with tricuspid aortic valve stenosis. In this article, we provide a thorough overview of the available clinical data regarding the outcomes of TAVI in BAV, from the perspective of an experienced TAVI center with over 150 TAVIs in this group of patients, performed in our institution since the year 2009. We present anatomical and clinical classifications of BAV, differences in outcomes in patients with bicuspid and tricuspid valves, as well as important topics regarding choice of an adequate valve and valve size.

Force distribution within the frame of self-expanding transcatheter aortic valve: Insights from in-vivo finite element analysis

We sought to assess the amount and distribution of force on the valve frame after transcatheter aortic valve replacement (TAVR) via patient-specific computer simulation. Patients successfully treated with the self-expanding Venus A-Valve and multislice computed tomography (MSCT) pre- and post-TAVR were retrospectively included. Patient-specific finite element models of the aortic root and prosthesis were constructed. The force (in Newton) on the valve frame was derived at every 3 mm from the inflow and at every 22.5° on each level. Twenty patients of whom 10 had bicuspid aortic valve (BAV) were analyzed. The total force on the frame was 74.9 N in median (interquartile range 24.0). The maximal force was observed at level 5 that corresponds with the nadir of the bioprosthetic leaflets and was 9.9 (7.1) N in all patients, 10.3 (6.6) N in BAV and 9.7 (9.2) N for patients with tricuspid aortic valve (TAV). The level of maximal force located higher from the native annulus in BAV and TAV patients (8.8 [4.8] vs. 1.8 [7.4] mm). The area of the valve frame at the level of maximal force decreased from 437.4 (239.7) mm² at the annulus to 377.6 (114.3) mm² in BAV, but increased from 397.5 (114.3) mm² at the annulus to 406.7 (108.9) mm² in TAV. The maximum force on the bioprosthetic valve frame is located at the plane of the nadir of the bioprosthetic leaflets. It remains to be elucidated whether this may be associated with bioprosthetic frame and leaflet integrity and/or function.

Transcatheter Aortic Valve Replacement for Bicuspid Aortic Valve Stenosis: A Practical Operative Overview

The bicuspid aortic valve (BAV) represents a complex anatomic scenario for transcatheter aortic valve replacement (TAVR) because of its unique technical challenges. As TAVR is moving towards younger and lower-risk populations, the proportion of BAV patients undergoing TAVR is expected to rise. Initial experiences of TAVR with first-generation transcatheter heart valves in high surgical risk patients with BAV stenosis showed higher rates of device failure and periprocedural complications as compared to tricuspid anatomy. The subsequent advances in imaging techniques and understanding of BAV anatomy, new iterations of transcatheter heart valves, and growing operators' experience yielded better outcomes. However, in the lack of randomized trials and rigorous evidence, the field of TAVR in BAV has been driven by empirical observations, with wide variability in transcatheter heart valve sizing and implantation techniques across different centers and operators. Thus, in this review article, we provide a fully illustrated overview of operative periprocedural steps for TAVR in BAV stenosis, though recognizing that it still remains anecdotal.

Expert Consensus on Sizing and Positioning of SAPIEN 3/Ultra in Bicuspid Aortic Valves

Severe aortic stenosis patients with bicuspid anatomy have been excluded from the major transcatheter aortic valve replacement (TAVI) randomized clinical trials. As a result, there is no official recommendation on bicuspid TAVI. A panel of bicuspid experts was created to fill this gap. In this consensus statement, an algorithm is proposed to guide the choice of surgery or TAVI within this complex patient population, depending on aortic dilatation, age, surgical risk score, and anatomy. A step-by-step guide for sizing and positioning of the SAPIEN 3/Ultra TAVI bioprostheses is presented. Annular sizing remains the primary strategy in most bicuspid patients. However, some anatomies may require sizing at the supra-annular level, for which patients the panel recommends the circle method, a dedicated sizing and positioning approach for SAPIEN 3/Ultra. The consensus provides valuable pre-operative insights on the interactions between SAPIEN 3/Ultra and the bicuspid anatomy; understanding the valve–anatomy relationship is critical to avoid complications and to optimize outcomes for patients.

Patient selection, procedural planning and interventional guidance for transcatheter aortic valve intervention

Transcatheter aortic valve replacement (TAVR) is an established treatment for severe aortic stenosis across a broad spectrum of patient risk profiles. Pre-procedural planning using multislice computed tomography (MSCT) is a fundamental component to ensure acute and long-term procedural success. MSCT can establish the procedural feasibility, the type vascular of approach as well as the device which is more likely to give a good result. Moreover, MSCT is a key tool to estimate the risk of potentially life-threatening complications. In this review, the role of MSCT for pre-procedural TAVR planning will be discussed providing a panoramic overview of the key elements that should be considered when performing TAVR. Additionally, the adjunctive role of fluoroscopy and echocardiography to plan and guide a TAVR procedure will also be discussed.

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

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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