A Strategy of Underexpansion and Ad Hoc Post-Dilation of Balloon-Expandable Transcatheter Aortic Valves in Patients at Risk of Annular Injury

Short-term outcome after transcatheter aortic valve replacement with a novel balloon-expandable valve

OBJECTIVES

Transcatheter aortic valve replacement (TAVR) has been expanding rapidly with numerous transcatheter heart valve (THV) systems currently available. The Myval balloon-expandable (BE) valve (Meril Life Sciences Pvt. Ltd., India) is a novel THV system indicated for the treatment of patients with severe aortic stenosis. The primary objective of this study is to assess the safety and performance of the Myval BE valve.

METHODS

In this prospective single-centre study, 120 consecutive patients who underwent TAVR with the Myval BE valve were included. Clinical outcomes were evaluated at 30 days and 6 months using Valve Academic Research Consortium‑2 criteria. All-cause mortality, stroke, acute kidney injury, major vascular complications, moderate or severe paravalvular leakage (PVL) and need for a permanent pacemaker implantation (PPI) were investigated.

RESULTS

At 6‑month follow-up, all-cause death and cardiac death were seen in 5.8% and 0.8% of the patients respectively. Periprocedural stroke and need for PPI were both seen in 3.3% of the patients. Access-site-related vascular and bleeding complications were absent. Improved valve haemodynamics and no moderate to severe PVL could be seen at 30 days. An intermediate valve size was selected in 51% of the patients.

CONCLUSIONS

The Myval BE valve demonstrates improved valve haemodynamics, absence of moderate to severe PVL and good safety outcomes at 6‑month follow-up with low cardiac death rate and acceptable rates of permanent pacemaker implantation and periprocedural stroke. Future randomised controlled trials will further establish the clinical utility of the Myval BE valve.

Delivery balloon volume positively correlates with the diameter and effective orifice area of implanted SAPIEN 3

BACKGROUND

In transcatheter aortic valve replacement (TAVR) using SAPIEN 3 (S3) (Edwards Lifesciences, Irvine, CA, USA), some clinicians decrease or increase the delivery balloon volume (VOL) when deploying S3 or conducting post-dilatation. However, the effects of controlling VOL on transcatheter heart valve diameter (THVD) and valve function remain unclear. We assessed associations among VOL, THVD, and effective orifice area (EOA) of S3.

METHODS

We enrolled patients undergoing TAVR using 23- and 26-mm S3 in Sendai Kousei Hospital between 2017 and 2019. VOL was controlled based on preprocedural computed tomography and intraprocedural transesophageal echocardiography (TEE). THVD were defined as the diameters of transcatheter heart valve at mid-level measured by TEE.

RESULTS

In enrolled 332 patients (23-mm, n = 188; 26-mm, n = 144), one (0.3%) and two (0.6%) developed annulus rupture and moderate/severe paravalvular leak, respectively. VOL at deployment was positively correlated with THVD on deployment (23-mm, r = 0.44, p < 0.001; 26-mm, r = 0.57, p < 0.001) and EOA (23-mm, r = 0.23, p = 0.0019; 26-mm, r = 0.22, p = 0.0094). In multiple regression analyses, VOL and post-dilatation were significant determinants of THVD, although aortic annulus area, calcium volume, and pre-dilatation were not. The areas under the receiver operating characteristic curve that were used to evaluate the accuracy of the index obtained by dividing THVD by body surface area (indexed THVD) to predict patient-prosthesis mismatch (PPM) were 0.744 and 0.811 in the 23- and 26-mm cohorts, respectively. A cut-off indexed THVD of ≤11.5 and 12.1 mm/m² well predicted PPM (23-mm, odds ratio, 5.20; 95% confidence interval, 1.33-20.3; 26-mm, odds ratio 14.1, 95% confidence interval 2.40-81.0).

CONCLUSION

VOL was positively correlated with THVD and EOA. Smaller indexed THVD was associated with a higher incidence of PPM. Controlling VOL under on-site THVD evaluation may be useful in reducing the PPM incidence.

Efficacy of larger valve sizing with underfilling in balloon-expandable transcatheter aortic valve replacement

OBJECTIVES

To investigate the efficacy and safety of larger valve sizing beyond the commercially recommended annular range in transcatheter aortic valve replacement (TAVR) with balloon-expandable transcatheter heart valve (THVs).

BACKGROUND

The clinical implications of larger balloon-expandable THV implantation with underfilling are poorly evaluated.

METHODS

This retrospective study included 692 consecutive patients who underwent TAVR with SAPIEN3. A total of 271 patients who underwent SAPIEN 3 implantation were analyzed based on three border zones (Zone 1: 300-345 mm² , 23 vs. 20 mm; Zone 2: 400-430 mm² , 26 vs. 23 mm; Zone 3: 500-546 mm² , 29 vs. 26 mm). The primary endpoint was the effective orifice area (EOA) assessed by echocardiography at 1 year, and secondary endpoints were a 30-day mortality rate, procedural complications during TAVR, and a composite of death from any cause and heart failure requiring rehospitalization at 1 year.

RESULTS

At 1-year follow-up, the EOA in the larger valve groups was greater than that in the recommended valve group in each zone (Zone 1: 1.45 ± 0.03 vs. 1.06 ± 0.06 cm² , p < 0.001; Zone 2: 1.83 ± 0.05 vs. 1.41 ± 0.05 cm² , p < 0.001; Zone 3: 1.93 ± 0.07 vs. 1.69 ± 0.07 cm² , p = 0.02). No significant difference in the secondary endpoint was observed in any of the zones.

CONCLUSIONS

Implantation of the out-of-range larger SAPIEN 3 THVs with underfilling was associated with greater EOA at the 1-year follow-up and feasible in the selected patients.

Late Balloon Valvuloplasty for Transcatheter Heart Valve Dysfunction

BACKGROUND

Transcatheter heart valve (THV) dysfunction with an elevated gradient or paravalvular leak (PVL) may be documented late after THV implantation. Medical management, paravalvular plugs, redo THV replacement, or surgical valve replacement may be considered. However, late balloon dilatation is rarely utilized because of concerns about safety or lack of efficacy.

OBJECTIVES

We aimed to evaluate the safety and efficacy of late dilatation in the management of THV dysfunction.

METHODS

All patients who underwent late dilatation for symptomatic THV dysfunction at 2 institutions between 2016 and 2021 were identified. Baseline, procedural characteristics, and clinical and echocardiographic outcomes were documented. THV frame expansion was assessed by multislice computed tomography before and after late dilatation.

RESULTS

Late dilatation was performed in 30 patients a median of 4.6 months (IQR: 2.3-11.0 months) after THV implantation in the aortic (n = 25; 83.3%), mitral (n = 2; 6.7%), tricuspid (n = 2; 6.7%) and pulmonary (n = 1; 3.3%) position. THV underexpansion was documented at baseline, and frame expansion substantially improved after late dilatation. The mean transvalvular gradient fell in all patients. For aortic THVs specifically, mean transaortic gradient fell from 25.4 ± 13.9 mm Hg to 10.8 ± 4.1 mm Hg; P < 0.001. PVL was reduced to ≤mild in all 11 patients with a previous >mild PVL. Embolic events, stroke, annular injury, and bioprosthetic leaflet injury were not observed. Symptomatic benefit was durable at 19.6 months (IQR: 14.8-36.1 months) follow-up.

CONCLUSIONS

Balloon dilatation late after THV implantation appears feasible and safe in appropriately selected patients and may result in THV frame expansion resulting in improvements in hemodynamic performance and PVL.

Application of Balloon-Expandable Transcatheter Heart Valve in Bicuspid Aortic Valve

Bicuspid aortic valve (BAV) remains challenging in transcatheter aortic valve replacement (TAVR) because of unfavorable anatomy. New-generation balloon-expandable valve (BEV) appears to be a valid alternative to surgery, especially in some Asian countries with a higher prevalence of BAV. This tutorial review summarizes current thinking about how to plan and implant BEV in BAVs using versatile techniques. First, the authors depict the main morphological characteristics of BAVs and their effects on the TAVR procedure. Next, the authors provide preprocedural analysis on sizing, obtaining the optimal deployment projection, and how to simplify valve-crossing. Finally, the authors provide step-by-step guidance on how to deploy the BEVs with evolved iterations in terms of specific anatomies, calcified annulus, and giant annulus.

Current and Future Aspects of Multimodal Imaging, Diagnostic, and Treatment Strategies in Bicuspid Aortic Valve and Associated Aortopathies

Bicuspid aortic valve (BAV) is the most frequent congenital cardiac abnormality leading to premature aortic valve apparatus dysfunction and is often associated with aortopathy. Therefore, current guidelines recommend a surgical aortic valve replacement (SAVR), even if many patients are deemed inoperable owing to their comorbidities and require alternatives such as transcatheter aortic valve replacement (TAVR). However, BAV variations remain challenging for procedural success. Therefore, the latest development in different imaging modalities (echocardiography, multislice-computertomographie, cardiovascular magnetic resonance) allows in-depth analysis for preprocedural risk stratification, follow up, and patient selection. Furthermore, we shed light on the latest developments in pre- and periprocedural fusion imaging as well as on current and future treatment options.

CT in planning transcatheter aortic valve implantation procedures and risk assessment

For surgical aortic valve replacement, the Society of Thoracic Surgeons score (STSS) is the reference standard for the prediction of operative risk. In transcatheter aortic valve implantation (TAVI) though, where the procedure itself is minimally invasive, the traditional risk assessment is supplemented by CTA. Through a consistent approach to the acquisition of high-quality images and the standardised reporting of annular measurements and adverse root and vascular features, patients at risk of complications can be identified. In turn, this may allow for a personalised procedural approach and treatment strategies devised to potentially reduce or mitigate this risk. This article provides a systematic and standardised approach to pre-procedural work-up with computed tomography angiography (CTA) and explores the current state of evidence and future areas of development in this rapidly developing field.

Radial Force: An Underestimated Parameter in Oversizing Transcatheter Aortic Valve Replacement Prostheses: In Vitro Analysis with Five Commercialized Valves

The goal is to inform in depth on transcatheter aortic valve replacement (TAVR) prosthesis mechanical behavior, depending on frame type, design, and size, and how it crucially impacts the oversizing issue in clinical use, and ultimately the procedure outcome. Transcatheter aortic valve replacement is an established therapy for high-risk patients suffering from aortic stenosis, and the indication for TAVR is progressively expanding to intermediate-risk patients. Choosing the optimal oversizing degree is crucial to safely anchor the TAVR valve-which involves limiting the risks for embolism, aortic regurgitation, conductance disturbance, or annulus rupture-and to increase the valve prosthesis performance. The radial force (RF) profiles of five TAVR prostheses were measured in vitro: the CoreValve 23 and 26 (Medtronic, Minneapolis, MN), the Acurate neo S (Symetis, Écublens, Vaud, Switzerland), and the SAPIEN XT 23 and 26 (Edwards Lifesciences, Irvine, CA). Measurements were run with the RX Machine equipment (Machine Solutions Inc., Flagstaff, AZ), which is used in ISO standard tests for intravascular stents. Test protocols were adapted for TAVR prostheses. With the prostheses RF profiles' results, mechanical behavior differences could be described and discussed in terms of oversizing strategy and clinical impact for all five valves. Besides, crossing the prostheses' RF profiles with their recommended size windows made the assessment of borderline size cases possible and helped analyze the risks when accurate measurement of patient aortic annulus proves difficult. The prostheses' RF profiles bring new support in clinical decision-making for valve type and size in patients.

Transcatheter Treatment of Bicuspid Aortic Valve Disease: Imaging and Interventional Considerations

Patients with bicuspid aortic valve disease have systematically been excluded from large randomized clinical trials investigating transcatheter aortic valve implantation (TAVI) due to their younger age, lower surgical risk and complex aortic anatomy. The asymmetric nature of the bicuspid valve orifice often accompanied by heavy regional calcification has led to concerns regarding valve positioning and expansion. Bicuspid aortic valve disease patients are at heightened risk of TAVI-related complications including coronary occlusion, aortic dissection and annular rupture, as well as the known risks of progressive aortopathy in these patients. These unique anatomical characteristics pose challenges for TAVI operators. However, with recent and ongoing refinements in implantation technique, improvements in pre-procedural imaging and iterations in device design, TAVI is emerging as a safe and feasible treatment option in this population. Paravalvular aortic regurgitation and high pacemaker rates have been the Achilles Heel for TAVI in bicuspid valve patients, yet newer generation devices are yielding promising results. Further studies are required before TAVI ultimately emerges as a viable option in low and intermediate surgical-risk patients with bicuspid valve disease. This review comprehensively summarizes the epidemiology, pathology and current evidence for TAVI in patients with bicuspid aortic valve disease. We also outline some practical tips for performing TAVI in these patients.

Computed Tomography Assessment for Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement has become a mainstream therapeutic option for patients with severe aortic stenosis who are at intermediate risk or high risk for surgical valve replacement. Computed tomography (CT) is now the standard imaging modality for preoperative vascular access planning an aortic annular sizing. This article reviews the established and potential future roles of CT in transcatheter aortic valve replacement.

Paravalvular Regurgitation after Transcatheter Aortic Valve Replacement: Comparing Transthoracic versus Transesophageal Echocardiographic Guidance

BACKGROUND

Transcatheter aortic valve replacement (TAVR) is increasingly being performed in cardiac catheterization laboratories using transthoracic echocardiography (TTE) to guide valve deployment. The risk of paravalvular regurgitation (PVR) remains a concern.

METHODS

We retrospectively reviewed 454 consecutive patients (mean age, 82 ± 8; 58% male) who underwent transfemoral TAVR at Emory Healthcare from 2007 to 2014. Two hundred thirty-four patients underwent TAVR in the cardiac catheterization laboratory with TTE guidance (TTE-TAVR; mean Society of Thoracic Surgeons score, 10%), while 220 patients underwent the procedure in the hybrid operating room with transesophageal echocardiography (TEE) guidance (TEE-TAVR; mean Society of Thoracic Surgeons score, 11%). All patients received an Edwards valve (SAPIEN 55%, SAPIEN-XT 45%). Clinical and procedural characteristics, echocardiographic parameters, and incidence of PVR were compared.

RESULTS

The incidence of at least mild PVR at discharge was comparable between TTE-TAVR and TEE-TAVR (33% vs 38%, respectively; P = .326) and did not differ when stratified by valve type. However, in the TTE-TAVR group, there was a higher incidence of second valve implantation (7% vs 2%; P = .026) and postdilation (38% vs 17%; P < .001) during the procedure. Although not independently associated with PVR at discharge (odds ratio = 1.12; 95% CI, 0.69-1.79), TTE-TAVR was associated with PVR-related events: the combined outcome of mild PVR at discharge, intraprocedural postdilation, and second valve insertion (odds ratio = 1.58; 95% CI, 1.01-2.46). There were no significant differences in PVR at 30 days, 6 months, and 1 year between the two groups.

CONCLUSIONS

TTE-TAVR in a high-risk group of patients was associated with increased incidence of intraprocedure PVR-related events, although it was not associated with higher rates of PVR at follow-up. Multicenter randomized trials are required to confirm the cost-effectiveness and safety of TTE-TAVR.