Effect of Mechanically Expanded vs Self-Expanding Transcatheter Aortic Valve Replacement on Mortality and Major Adverse Clinical Events in High-Risk Patients With Aortic Stenosis: The REPRISE III Randomized Clinical Trial

Transcatheter Aortic Valve Replacement in Low-risk Patients With Bicuspid Aortic Valve Stenosis

Importance

The outcomes of transcatheter aortic valve replacement (TAVR) in low-risk patients with bicuspid aortic valve stenosis have not been studied in a large scale, multicentered, prospective fashion.

Objective

To evaluate the procedural safety, efficacy, and 30-day outcomes of TAVR in patients with bicuspid aortic stenosis at low surgical risk.

Design, Setting, and Participants

The Low Risk Bicuspid Study is a prospective, single-arm trial study with inclusion/exclusion criteria developed from the Evolut Low Risk Randomized Trial. Follow-up is planned for 10 years. Patients underwent TAVR at 25 centers in the United States who were also participating in the Evolut Low Risk Randomized Trial from December 2018 to October 2019. Eligible patients had severe bicuspid aortic valve stenosis and met American Heart Association/American College of Cardiology guideline indications for aortic valve replacement.

Interventions

Patients underwent attempted implant of an Evolut or Evolut PRO transcatheter aortic valve, with valve size based on annular measurements.

Main Outcomes and Measures

The prespecified primary end point was the incidence of all-cause mortality or disabling stroke at 30 days. The prespecified primary efficacy end point was device success defined as the absence of procedural mortality, the correct position of 1 bioprosthetic heart valve in the proper anatomical location, and the absence of more than mild aortic regurgitation postprocedure.

Results

A total of 150 patients underwent an attempted implant. Baseline characteristics include mean age of 70.3 (5.5) years, 48.0% female (n = 72), and a mean Society of Thoracic Surgeons score of 1.4 (0.6%). Most patients (136; 90.7%) had Sievers type I valve morphology. The incidence of all-cause mortality or disabling stroke was 1.3% (95% CI, 0.3%-5.3%) at 30 days. The device success rate was 95.3% (95% CI, 90.5%-98.1%). At 30 days, the mean (SD) AV gradient was 7.6 (3.7) mm Hg and effective orifice area was 2.3 (0.7) cm2. A new permanent pacemaker was implanted in 22 patients (15.1%). No patients had greater than mild paravalvular leak.

Conclusions and Relevance

Transcatheter aortic valve replacement in low-surgical risk patients with bicuspid aortic valve stenosis achieved favorable 30-day results, with low rates of death and stroke and high device success rate.

Trial Registration

ClinicalTrials.gov Identifier: NCT03635424.

Comparison of Self-Expanding Bioprostheses for Transcatheter Aortic Valve Replacement in Patients With Symptomatic Severe Aortic Stenosis

Background:

Few randomized trials have compared bioprostheses for transcatheter aortic valve replacement, and no trials have compared bioprostheses with supra-annular design. The SCOPE 2 trial (Safety and Efficacy Comparison of Two TAVI Systems in a Prospective Randomized Evaluation 2) was designed to compare the clinical outcomes of the ACURATE neo and CoreValve Evolut bioprostheses for transcatheter aortic valve replacement.

Methods:

SCOPE 2 was a randomized trial performed at 23 centers in 6 countries between April 2017 and April 2019. Patients ≥75 years old with an indication for transfemoral transcatheter aortic valve replacement as agreed by the heart team were randomly assigned to receive treatment with either the ACURATE neo (n=398) or the CoreValve Evolut bioprostheses (n=398). The primary end point, powered for noninferiority of the ACURATE neo bioprosthesis, was all-cause death or stroke at 1 year. The key secondary end point, powered for superiority of the ACURATE neo bioprosthesis, was new permanent pacemaker implantation at 30 days.

Results:

Among 796 randomized patients (mean age, 83.2±4.3 years; mean Society of Thoracic Surgeons Predicted Risk of Mortality score, 4.6±2.9%), clinical follow-up information was available for 778 (98%) patients. Within 1 year, the primary end point occurred in 15.8% of patients in the ACURATE neo group and in 13.9% of patients in the CoreValve Evolut group (absolute risk difference, 1.8%, upper 1-sided 95% confidence limit, 6.1%; P =0.0549 for noninferiority). The 30-day rates of new permanent pacemaker implantation were 10.5% in the ACURATE neo group and 18.0% in the CoreValve Evolut group (absolute risk difference, –7.5% [95% CI, –12.4 to –2.60]; P =0.0027). No significant differences were observed in the components of the primary end point. Cardiac death at 30 days (2.8% versus 0.8%; P =0.03) and 1 year (8.4% versus 3.9%; P =0.01), and moderate or severe aortic regurgitation at 30 days (10% versus 3%; P =0.002) were significantly increased in the ACURATE neo group.

Conclusions:

Transfemoral transcatheter aortic valve replacement with the self-expanding ACURATE neo did not meet noninferiority compared with the self-expanding CoreValve Evolut in terms of all-cause death or stroke at 1 year, and it was associated with a lower incidence of new permanent pacemaker implantation. In secondary analyses, the ACURATE neo was associated with more moderate or severe aortic regurgitation at 30 days and cardiac death at 30 days and 1 year.

Registration:

URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03192813.

Transcatheter Aortic Valve Replacement With the LOTUS Edge System: Early European Experience

OBJECTIVES

The aim of this study was to evaluate the short-term safety and efficacy of transcatheter aortic valve replacement (TAVR) with the LOTUS Edge system.

BACKGROUND

The LOTUS Edge system was commercially re-released in April 2019. The authors report the first European experience with this device.

METHODS

A multicenter, single-arm, retrospective registry was initiated to evaluate short-term clinical outcomes. Included cases are the first experience with this device and new implantation technique in Europe. Clinical, echocardiographic, and computed tomographic data were analyzed. Endpoints were defined according to Valve Academic Research Consortium-2 and were site reported.

RESULTS

Between April and November 2019, 286 consecutive patients undergoing TAVR with the LOTUS Edge system at 18 European centers were included. The mean age and Society of Thoracic Surgeons score were 81.2 ± 6.9 years and 5.2 ± 5.4%, respectively. Nearly one-half of all patients (47.9%) were considered to have complex anatomy. Thirty-day major adverse events included death (2.4% [n = 7]) and stroke (3.5% [n = 10]). After TAVR, the mean aortic valve area was 1.9 ± 0.9 cm², and the mean transvalvular gradient was 11.9 ± 5.7 mm Hg. None or trace paravalvular leak (PVL) occurred in 84.4% and moderate PVL in 2.0%. There were no cases of severe PVL. New permanent pacemaker (PPM) implantation was required in 25.9% among all patients and 30.8% among PPM-naive patients.

CONCLUSIONS

Early experience with the LOTUS Edge system demonstrated satisfactory short-term safety and efficacy, favorable hemodynamic data, and very low rates of PVL in an anatomically complex cohort. New PPM implantation remained high. Further study will evaluate if increasing operator experience with the device and new implantation technique can reduce the incidence of PPM implantation.

General Versus Local Anesthesia With Conscious Sedation in Transcatheter Aortic Valve Implantation

Background:

In clinical practice, local anesthesia with conscious sedation (CS) is performed in roughly 50% of patients undergoing transcatheter aortic valve replacement. However, no randomized data assessing the safety and efficacy of CS versus general anesthesia (GA) are available.

Methods:

The SOLVE-TAVI (Comparison of Second-Generation Self-Expandable Versus Balloon-Expandable Valves and General Versus Local Anesthesia in Transcatheter Aortic Valve Implantation) trial is a multicenter, open-label, 2×2 factorial, randomized trial of 447 patients with aortic stenosis undergoing transfemoral transcatheter aortic valve replacement comparing CS versus GA. The primary efficacy end point was powered for equivalence (equivalence margin 10% with significance level 0.05) and consisted of the composite of all-cause mortality, stroke, myocardial infarction, infection requiring antibiotic treatment, and acute kidney injury at 30 days.

Results:

The primary composite end point occurred in 27.2% of CS and 26.4% of GA patients (rate difference, 0.8 [90% CI, −6.2 to 7.8]; P equivalence =0.015). Event rates for the individual components were as follows: all-cause mortality, 3.2% versus 2.3% (rate difference, 1.0 [90% CI, −2.9 to 4.8]; P equivalence <0.001); stroke, 2.4% versus 2.8% (rate difference, −0.4 [90% CI, −3.8 to 3.8]; P equivalence <0.001); myocardial infarction, 0.5% versus 0.0% (rate difference, 0.5 [90% CI, −3.0 to 3.9]; P equivalence <0.001), infection requiring antibiotics 21.1% versus 22.0% (rate difference, −0.9 [90% CI, −7.5 to 5.7]; P equivalence =0.011); acute kidney injury, 9.0% versus 9.2% (rate difference, −0.2 [90% CI, −5.2 to 4.8]; P equivalence =0.0005). There was a lower need for inotropes or vasopressors with CS (62.8%) versus GA (97.3%; rate difference, −34.4 [90% CI, −41.0 to −27.8]).

Conclusions:

Among patients with aortic stenosis undergoing transfemoral transcatheter aortic valve replacement, use of CS compared with GA resulted in similar outcomes for the primary efficacy end point. These findings suggest that CS can be safely applied for transcatheter aortic valve replacement.

Registration:

URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02737150.

Hemodynamic comparison of transcatheter aortic valve replacement with the SAPIEN 3 Ultra versus SAPIEN 3: The HomoSAPIEN registry

Objectives

The study aims to compare the hemodynamic and clinical outcomes of the SAPIEN 3 Ultra (S3‐Ultra) with the SAPIEN 3 (S3) system in patients who underwent transfemoral transcatheter aortic valve replacement (TF‐TAVR).

Background

The new balloon‐expandable S3‐Ultra system incorporates new features to reduce paravalvular leakage (PVL). However, the data after the S3‐Ultra implantation is very limited.

Methods

A total of 282 consecutive patients who underwent TF‐TAVR with the S3‐Ultra and the S3 were evaluated. The primary outcome of this study was to compare the incidence of ≥mild PVL after the S3‐Ultra and S3 implantation.

Results

Between June 2017 and November 2019, 141 patients with the S3‐Ultra and 141 patients with the S3 were identified with similar baseline and preprocedural imaging characteristics (mean age: 79.6 ± 6.7 years and mean aortic annulus area: 492.5 ± 91.2 mm²). In total, 83 patients (29.4%) were treated with 29‐mm valve. Predischarge echocardiography demonstrated a significantly lower incidence of ≥mild PVL (the total cohort: 7.2 vs. 22.3%, p < .001, and the cohort excluding 29‐mm valve: 4.0 vs. 21.4%, p = .03) for the S3‐Ultra. The S3‐Ultra system, especially 20‐, 23‐, and 26‐mm valve, was associated with significantly lower risk of ≥mild PVL compared with the S3 system in multivariate analysis. There were no significant differences in clinical outcomes at 30‐day between these groups, except for the lower incidence of major vascular complication (4.5 vs. 11.4%, p = .05) in patients with the S3‐Ultra.

Conclusions

In this registry, the S3‐Ultra system performed superiorly to the S3, as demonstrated by reduced ≥mild PVL, with comparable safety.

Considerations for Optimal Device Selection in Transcatheter Aortic Valve Replacement: A Review

Importance

Aortic valve stenosis (AS) is the most common manifestation of acquired valvular heart disease in developed countries. Several large-scale randomized clinical trials investigating the entire spectrum of patients with severe symptomatic AS from low to prohibitive risk have established transcatheter aortic valve replacement (TAVR) as a safe and effective alternative to surgical aortic valve replacement.

Observations

There are currently only 3 types of TAVR devices commercially available in the US, but several other valve types are undergoing clinical trials in the US. Because of fundamental differences in engineering features, each TAVR device type has specific strengths and limitations. This review aims to provide an overview of design features and clinical outcomes of various TAVR devices that are either commercially available or undergoing clinical investigation.

Conclusions and Relevance

Given the lack of large-scale head-to-head comparisons of various TAVR devices and the rapid development of new device iterations, there is insufficient evidence to claim superiority of one device type over another. Nonetheless, as each TAVR device has unique design characteristics, certain patient-related and anatomy-related factors may slightly favor one or several particular designs.

Delayed Coronary Obstruction after Transcatheter Aortic Valve Replacement - An Uncommon But Serious Complication

As transcatheter aortic valve replacement (TAVR) becomes the mainstream treatment for valvular aortic stenosis, it is vitally important to recognize its associated procedural complications. Among the clinically relevant but uncommonly seen complications, the development of delayed coronary obstruction (DCO) occurring during the early post-procedural phase or even later following the index TAVR procedure, has been reported. These reports have raised concerns as TAVR comes more common in lower-risk patients. In this review article, we explored the implications of DCO for pre-procedural computed tomography evaluation, valve selection and sizing, intra-procedural manipulation, and approaches to post-procedural management.

Clinical Implications of Physical Function and Resilience in Patients Undergoing Transcatheter Aortic Valve Replacement

Background

Gait speed is a reliable measure of physical function and frailty in patients with aortic stenosis undergoing transcatheter aortic valve replacement (TAVR). Slow gait speed pre‐TAVR predicts worse clinical outcomes post‐TAVR. The consequences of improved versus worsened physical function post‐TAVR are unknown.

Methods and Results

The REPRISE III (Repositionable Percutaneous Replacement of Stenotic Aortic Valve Through Implantation of Lotus Valve System–Randomized Clinical Evaluation) trial randomized high/extreme risk patients to receive a mechanically‐expanded or self‐expanding transcatheter heart valve. Of 874 patients who underwent TAVR, 576 with complete data at baseline and 1 year were included in this analysis. Slow gait speed in the 5‐m walk test was defined as <0.83 m/s. A clinically meaningful improvement (≥0.1 m/s) in gait speed 1 year after TAVR occurred in 39% of patients, 35% exhibited no change, and 26% declined (≥0.1 m/s). Among groups defined by baseline/1‐year post‐TAVR gait speeds, 1‐ to 2‐year mortality or hospitalization rates were as follows: 6.6% (normal/normal), 8.0% (slow/normal), 20.9% (normal/slow), and 21.5% (slow/slow). After adjustment, slow gait speed at 1 year (regardless of baseline speed) was associated with a 3.5‐fold increase in death/hospitalization between 1 and 2 years compared with those with normal baseline/1‐year gait speed. Patients whose slow gait speed normalized at 1 year had no increased risk. One‐year, but not baseline, gait speed was associated with death or hospitalization between 1 and 2 years (adjusted hazard ratio, 0.83 per 0.1 m/s faster gait; 95% CI, 0.74–0.93, P=0.001).

Conclusions

Marked heterogeneity exists in the trajectory of physical function after TAVR and this, more than baseline function, has clinical consequences. Identifying and optimizing factors associated with physical resilience after TAVR may improve outcomes.

Registration

URL: https://www.clini​caltr​ials.gov; Unique identifier: NCT02202434.

Meta-analysis Comparing Outcomes of Self-Expanding Versus Balloon-Expandable Valves for Transcatheter Aortic Valve Implantation

There are two commercially available transcatheter heart valve systems: balloon expandable valves (BEV) and self-expanding valves (SEV). However, there is a paucity of randomized trials comparing both systems. Electronic databases (Medline, the Cochrane Library, Web of Science, and clinicaltrials.gov) and major conference proceedings were searched for randomized trials of patients with symptomatic severe aortic stenosis and received transcatheter aortic valve implantation (TAVI) with a SEV or BEV or surgical aortic valve replacement. The main efficacy outcomes were all-cause mortality and stroke at the longest available follow-up. The main analysis was performed using a random-effects network meta-analysis complemented by several subgroup and sensitivity analyses. Ten trials with 9,439 patients (mostly undergoing transfemoral TAVI) were included. At a median of 27 months, there was no difference between BEV and SEV valves in terms of all-cause mortality (odds ratio [OR] 1.05, 95% confidence interval [CI] 0.79 to 1.42). The incidence of any stroke was higher with BEV (OR 1.51, 95% CI 1.01 to 2.26), but there was no difference in the incidence of disabling stroke. At 30-days, BEV valves were associated with lower incidence of new permanent pacemaker placement (OR 0.50, 95% CI 0.32 to 0.79) and moderate/severe paravalvular regurgitation (OR 0.39, 95% CI 0.22 to 0.68). In conclusion, in patients with severe symptomatic aortic stenosis undergoing transfemoral TAVI, SEV and BEV were associated with similar all-cause mortality. BEV were associated with a higher incidence of any stroke driven by nondisabling strokes, but lower incidence of new permanent pacemaker placement and moderate/severe paravalvular regurgitation compared with SEV.

Intraventricular Conduction Disturbances After Transcatheter Aortic Valve Implantation

Despite significant improvements in transcatheter aortic valve implantation (TAVI) outcomes, periprocedural conduction disturbances, such as new-onset left bundle branch block (LBBB) and new pacemaker implantation (PMI), remain relatively frequent concerns. The development of periprocedural conduction disturbances can be explained by the proximity between the aortic valve and the conduction system. Although prior studies reported heterogeneity in PMI rates after TAVI, current evidence supports the potentially deleterious consequence of LBBB and PMI, and several predisposing factors have been reported. Therefore, new strategies to avoid conduction disturbances and to improve their management are required, particularly with the current trend to expand TAVI to a low-risk population.

Safety Profile of an Intra-Annular Self-Expanding Transcatheter Aortic Valve and Next-Generation Low-Profile Delivery System

OBJECTIVES

The aim of this study was to characterize the safety profile of an intra-annular self-expanding valve with a next-generation low-profile delivery system (DS).

BACKGROUND

Key design modifications to the FlexNav DS include the addition of a hydrophilic-coated, integrated sheath and stability layer to facilitate gradual, controlled deployment in vessels with diameter ≥5 mm.

METHODS

Patients were pooled from 2 concurrent prospective, multicenter, single-arm studies (FlexNav DS arm of PORTICO IDE [Portico Re-Sheathable Transcatheter Aortic Valve System U.S. IDE Trial] [n = 134] and the FlexNav EU CE Mark Study [n = 46]) for the analysis. The primary endpoint was Valve Academic Research Consortium-2-defined major vascular complications at 30 days. Clinical outcomes and valve performance were assessed through 30 days by an independent clinical events committee and an echocardiography core laboratory, respectively.

RESULTS

One hundred forty high-risk and 40 extreme-risk subjects enrolled between October 15, 2018, and December 10, 2019, from 28 sites in the United States, Australia, and Europe who underwent attempted transfemoral Portico valve implantation were included. The mean age was 85.1 ± 5.6 years, 60% were women, the mean Society of Thoracic Surgeons score was 5.3%, and 96.1% presented with ≥1 frailty factor. Technical device success was 96.7%. At 30 days, the rate of major vascular complications was 5.0%, with 4.4% of complications adjudicated as access site-related (3.3% transcatheter aortic valve replacement DS access site-related). Death (0.6%) and disabling stroke (1.1%) were rare. The rate of new permanent pacemaker implantation was 15.4%. Echocardiography revealed a mean gradient of 7.1 ± 3.2 mm Hg, mean valve area of 1.77 ± 0.41 cm², and a 4.1% rate of moderate paravalvular leak at 30 days.

CONCLUSIONS

Portico valve implantation with the FlexNav DS was associated with an excellent safety profile at 30 days.

The Sky Is Not Falling: Surgical Perspectives on a New Transcatheter Paradigm

The role of cardiac surgeons in the treatment of aortic valve disease is changing with the expansion of transcatheter aortic valve replacement. Recent trials in patients at low surgical risk will further this paradigm shift, and the future cardiac surgeons in this space remain uncertain. In this Viewpoint article, we discuss the role that surgeons can play in the future of structural heart medicine. We examine the potential effects of the low-risk transcatheter aortic valve replacement trials on overall operative volumes and how these effects may be limited through structured training programs and strong collaboration within the heart team. Finally, future considerations and cautions for the cardiac surgical community are discussed. The coming era presents an opportunity for growth, leadership, and strong interdisciplinary collaboration for the cardiac surgery community.

Management of Coronary Artery Disease in the Setting of Transcatheter Aortic Valve Replacement

Aortic stenosis and coronary artery disease (CAD) frequently co-exist, as they share a common pathophysiology and risk factors. Due to lack of randomised controlled trials (RCTs) and exclusion of significant CAD in transcatheter aortic valve replacement (TAVR) trials, the optimal method of revascularisation of CAD in patients undergoing TAVR remains unknown. Observational studies and meta-analyses have shown varied results in outcomes for patients with CAD undergoing TAVR, and no significant difference in post-TAVR outcomes in patients who underwent revascularisation either prior to or during TAVR versus those who did not. However, some observational studies have shown that patients with lower residual SYNTAX score (rSS) post-revascularisation have better outcomes post-TAVR compared to those with higher rSS. RCTs are needed to clearly understand whether revascularisation is beneficial in these patients. Until then, management of CAD in patients undergoing TAVR must be individualised based on discussion with the heart team.

Network Meta-analysis of Surgical Aortic Valve Replacement and Different Transcatheter Heart Valve Systems for Symptomatic Severe Aortic Stenosis

BACKGROUND

Although different transcatheter heart valve (THV) systems have been introduced to overcome transcatheter aortic valve replacement (TAVR)-specific complications, head-to-head comparisons of these THV systems are scarce. The aim of this study was to compare different THV systems and surgical aortic valve replacement (SAVR) by conducting a network meta-analysis.

METHODS

PubMed and EMBASE were searched through November 2019 for studies comparing safety and efficacy of balloon-expandable valve (BEV), self-expanding valve (SEV), mechanically expandable valve (MEV), and SAVR for symptomatic severe aortic stenosis. End points in the short term at 30 days or discharge and the long term up to 2 years were assessed.

RESULTS

We identified 11 randomized controlled trials with a total of 10,300 patients eligible for inclusion in our study. There were no significant differences in all-cause death among different THV systems and SAVR in both short and long terms. Disabling stroke was significantly lower with MEV vs BEV and SAVR (hazard ratios [HRs] 0.31 [95% confidence interval [CI] 0.12-0.77] and 0.33 [95% CI 0.14-0.76], respectively) in the long term. MEV was associated with an increased risk of new permanent pacemaker implantation compared with BEV, SEV, and SAVR (HRs 3.82 [95% CI 1.83-7.97], 1.85 [95% CI 1.02-3.36], and 5.23 [95% CI 2.61-10.47], respectively) in the long term.

CONCLUSIONS

In patients with symptomatic severe aortic stenosis undergoing intervention, there were no significant differences in all-cause death among different THV systems and SAVR. MEV had low frequency of disabling stroke compared with BEV and SAVR, but an increased frequency of permanent pacemaker implantation compared with other interventions.

3-Dimensional printing to predict paravalvular regurgitation after transcatheter aortic valve replacement

BACKGROUND

There is no effective method to predict paravalvular regurgitation prior to transcatheter aortic valve replacement (TAVR).

METHODS

We retrospectively analyzed pre-TAVR computed tomography (CT) scans of 20 patients who underwent TAVR for severe, calcific aortic stenosis and subsequently printed 3-dimensional (3D) aortic root models of each patient. Models were printed using Ninjaflex thermoplastic polyurethane (TPU) (Ninjatek Manheim, PA) and TPU 95A (Ultimaker, Netherlands) on Ultimaker 3 Extended 3D printer (Ultimaker, Netherlands). The models were implanted at nominal pressure with same sized Sapien balloon-expandable frames (Edwards Lifesciences, CA) as received in-vivo. Ex-vivo implanted TAVR models (eTAVR) were scanned using Siemens SOMATOM flash dual source CT (Siemens, Malvern, PA) and then analyzed with Mimics software (Materialize NV, Leuven, Belgium) to evaluate relative stent appositions. eTAVR were then compared to post-TAVR echocardiograms for each patient to assess for correlations of identified and predicted paravalvular leak (PVL) locations.

RESULTS

A total of 20 patients (70% male) were included in this study. The median age was 77.5 (74-83.5) years. Ten patients were characterized to elicit mild (9/10) or moderate (1/10) PVL, and 10 patients presented no PVL. In patients with echocardiographic PVL, eTAVR 3D model analyses correctly identified the site of PVL in 8/10 cases. In patients without echocardiographic PVL, eTAVR 3D model analyses correctly predicted the lack of PVL in 9/10 cases.

CONCLUSION

3D printing may help predict the potential locations of associated PVL post-TAVR, which may have implications for optimizing valve selection and sizing.

Comparison of newer generation self-expandable vs. balloon-expandable valves in transcatheter aortic valve implantation: the randomized SOLVE-TAVI trial

Aims

Transcatheter aortic valve implantation (TAVI) has emerged as established treatment option in patients with symptomatic aortic stenosis. Technical developments in valve design have addressed previous limitations such as suboptimal deployment, conduction disturbances, and paravalvular leakage. However, there are only limited data available for the comparison of newer generation self-expandable valve (SEV) and balloon-expandable valve (BEV).

Methods and results

SOLVE-TAVI is a multicentre, open-label, 2 × 2 factorial, randomized trial of 447 patients with aortic stenosis undergoing transfemoral TAVI comparing SEV (Evolut R, Medtronic Inc., Minneapolis, MN, USA) with BEV (Sapien 3, Edwards Lifesciences, Irvine, CA, USA). The primary efficacy composite endpoint of all-cause mortality, stroke, moderate/severe prosthetic valve regurgitation, and permanent pacemaker implantation at 30 days was powered for equivalence (equivalence margin 10% with significance level 0.05). The primary composite endpoint occurred in 28.4% of SEV patients and 26.1% of BEV patients meeting the prespecified criteria of equivalence [rate difference −2.39 (90% confidence interval, CI −9.45 to 4.66); Pequivalence = 0.04]. Event rates for the individual components were as follows: all-cause mortality 3.2% vs. 2.3% [rate difference −0.93 (90% CI −4.78 to 2.92); Pequivalence &lt; 0.001], stroke 0.5% vs. 4.7% [rate difference 4.20 (90% CI 0.12 to 8.27); Pequivalence = 0.003], moderate/severe paravalvular leak 3.4% vs. 1.5% [rate difference −1.89 (90% CI −5.86 to 2.08); Pequivalence = 0.0001], and permanent pacemaker implantation 23.0% vs. 19.2% [rate difference −3.85 (90% CI −10.41 to 2.72) in SEV vs. BEV patients; Pequivalence = 0.06].

Conclusion

In patients with aortic stenosis undergoing transfemoral TAVI, newer generation SEV and BEV are equivalent for the primary valve-related efficacy endpoint. These findings support the safe application of these newer generation percutaneous valves in the majority of patients with some specific preferences based on individual valve anatomy.

Transcatheter aortic valve replacement in low risk patients: a review of PARTNER 3 and Evolut low risk trials

Transcatheter aortic valve replacement (TAVR) has become a mainstay in treatment for patients with severe aortic stenosis who are considered high-risk surgical candidates. The use of TAVR in low-risk patients with severe aortic stenosis is being explored as an alternative to surgical aortic valve replacement (SAVR). Recent results from the Medtronic Evolut Low Risk trial and the Placement of Aortic Transcatheter Valves (PARTNER) 3 trial shed light on the use of TAVR in low-risk surgical candidates. The Evolut Low Risk trial compared TAVR with a self-expanding supra-annular bioprosthesis to SAVR in 1468 patients with severe aortic stenosis who were low surgical risk. Patients with a mean age of 74 and a mean Society of Thoracic Surgeons (STS) risk score of 1.9% were randomized to either TAVR or SAVR groups. Using the composite end point of death or disabling stroke at 24 months, the study found an incidence of 5.3% in the TAVR arm and 6.7% in the surgical arm. The Evolut Low Risk trial thus concluded that TAVR was statistically noninferior but not superior to SAVR (difference, -1.4 percentage points; 95% Bayesian credible interval for the difference, -4.9 to 2.1; posterior probability of noninferiority, >0.999). The PARTNER 3 trial assigned 1,000 patients with severe aortic stenosis and low surgical risk to either TAVR with transfemoral placement of balloon expandable valve or SAVR. Patients with a mean age of 73 and a mean STS score of 1.9% were randomized to either TAVR or SAVR groups. With respect to the primary endpoint of composite death from any cause, stroke, or rehospitalization, the study found an occurrence of 8.5% in TAVR and 15.1% in SAVR, confirming both noninferiority and superiority in the TAVR group [absolute difference, -6.6 percentage points; 95% confidence interval (CI), -10.8 to -2.5; P<0.001 for noninferiority; hazard ratio, 0.54; 95% CI, 0.37 to 0.79; P=0.001 for superiority]. Both the Evolut low risk trial and the PARTNER 3 trial provide evidence that the use of TAVR extends beyond the scope of high and intermediate risk surgical patients and is at the very least equivalent to SAVR in the treatment low-risk surgical candidates when using a transfemoral approach in patients without bicuspid aortic valves. In this article we provide an extensive review on the Evolute low risk and PARTNER 3 trials, including a discussion on clinically relevant outcomes.

Two-Year Outcomes After Transcatheter Aortic Valve Replacement With Mechanical vs Self-expanding Valves: The REPRISE III Randomized Clinical Trial

Importance

To our knowledge, REPRISE III is the first large randomized comparison of 2 different transcatheter aortic valve replacement platforms: the mechanically expanded Lotus valve (Boston Scientific) and self-expanding CoreValve (Medtronic).

Objective

To evaluate outcomes of Lotus vs CoreValve after 2 years.

Design, Setting, and Participants

A total of 912 patients with high/extreme risk and severe, symptomatic aortic stenosis enrolled between September 22, 2014, and December 24, 2015, were randomized 2:1 to receive Lotus (607 [66.6%]) or CoreValve (305 [33.4%] at 55 centers in North America, Europe, and Australia. The first 2-year visit occurred on October 17, 2016, and the last was conducted on April 12, 2018. Clinical and echocardiographic assessments are complete through 2 years and will continue annually through 5 years.

Main Outcomes and Measures

All-cause mortality and all-cause mortality or disabling stroke at 2 years. Other clinical factors included overall stroke, disabling stroke, repeated procedures, rehospitalization, valve thrombosis, and pacemaker implantation. Echocardiographic analyses included effective orifice area, mean gradient, and paravalvular leaks (PVLs).

Results

Of 912 participants, the mean (SD) age was 82.8 (7.3) years, 465 (51%) were women, and the mean (SD) Society of Thoracic Surgeons predicted risk of mortality was 6.8% (4.0%). At 2 years, all-cause death was 21.3% with Lotus vs 22.5% with CoreValve (hazard ratio [HR], 0.94; 95% CI, 0.69-1.26; P = .67) and all-cause mortality or disabling stroke was 22.8% with Lotus and 27.0% with CoreValve (HR, 0.81; 95% CI, 0.61-1.07; P = .14). Overall stroke was 8.4% vs 11.4% (HR, 0.75; 95% CI, 0.48-1.17; P = .21); disabling stroke was more frequent with CoreValve vs Lotus (4.7% Lotus vs 8.6% CoreValve; HR, 0.53; 95% CI, 0.31-0.93; P = .02). More Lotus patients received a new permanent pacemaker (41.7% vs 26.1%; HR, 1.87; 95% CI, 1.41-2.49; P < .01) or had a valve thrombosis (3.0% vs 0.0%; P < .01) compared with CoreValve. More patients who received CoreValve experienced a repeated procedure (0.6% Lotus vs 2.9% CoreValve; HR, 0.19; 95% CI, 0.05-0.70; P < .01), valve migration (0.0% vs 0.7%; P = .05), or embolization (0.0% vs 2.0%; P < .01) than Lotus. Valve areas remained significantly larger and the mean gradient was lower with CoreValve than Lotus (valve area, mean [SD]: Lotus, 1.53 [0.49] cm2 vs CoreValve, 1.76 [0.51] cm2; P < .01; valve gradient, mean [SD]: Lotus, 13.0 [6.7] mm Hg vs 8.1 [3.7] mm Hg; P < .01). Moderate or greater PVL was more frequent with CoreValve (0.3% Lotus vs 3.8% CoreValve; P < .01) at 2 years. Larger improvements in New York Heart Association (NYHA) functional class were observed with Lotus compared with CoreValve (improved by ≥1 NYHA class: Lotus, 338 of 402 [84.1%] vs CoreValve, 143 of 189 [75.7%]; P = .01; improved by ≥2 NYHA classes: 122 of 402 [37.3%] vs 65 of 305 [21.3%]).

Conclusions and Relevance

After 2 years, all-cause mortality rates, mortality or disabling stroke were similar between Lotus and CoreValve. Disabling stroke, functional class, valve migration, and PVL favored the Lotus arm whereas valve hemodynamics, thrombosis, and new pacemaker implantation favored the CoreValve arm.

Trial Registration

clinicaltrials.gov Identifier: NCT02202434.

Safety and Performance Outcomes of a Self-Expanding Transcatheter Aortic Heart Valve: The BIOVALVE Trials

OBJECTIVES

The aim of this study was to assess the safety and performance of a newly introduced transfemoral self-expanding supra-annular transcatheter heart valve.

BACKGROUND

Transcatheter aortic valve replacement has become an established procedure, and newer transcatheter heart valves aim to supplement the current armamentarium.

METHODS

BIOVALVE-I is a prospective, single-center feasibility study enrolling 13 high-risk patients with severe aortic stenosis, and BIOVALVE-II is a multicenter pilot study enrolling a further 55 patients under the same protocol.

RESULTS

Patients' mean age was 82.4 ± 5.3 years, 57.4% had concomitant coronary artery disease, 50.0% had renal insufficiency stage ≥3, 32.4% had diabetes mellitus, 29.4% had current anemia, 19.1% had chronic obstructive pulmonary disease, 19.1% were frail, and 17.6% had prior cerebrovascular events. The primary endpoint, early safety according to the Valve Academic Research Consortium-2 guidelines, was observed in 13 patients (19.1%). One patient (1.5%) died through 30 days of a noncardiac cause, and 4 patients (7.8%) died through 180 days. Disabling stroke occurred at 30 days in 1 patient (1.5%) and at 180 days in 2 patients (3.2%). New permanent pacemakers up to 30 days were implanted in 9 patients (13.4%). Two patients (3.8%) had moderate or severe paravalvular leakage at 30 days and 4 (9.1%) at 6 months, mean effective orifice area was 2.0 ± 0.4 cm² and 1.9 ± 0.5 cm², and mean gradient was 6.4 mm Hg at 30 days and 6 months.

CONCLUSIONS

Clinical outcomes with the Biovalve self-expanding transcatheter heart valve were similar to those seen in other first-in-human studies with first-generation devices for severe aortic stenosis.

Multicentre propensity-matched comparison of transcatheter aortic valve implantation using the ACURATE TA/neo self-expanding versus the SAPIEN 3 balloon-expandable prosthesis

AIMS

In the absence of randomised data, we aimed to compare the transapical ACURATE and transfemoral ACURATE neo with the SAPIEN 3 prosthesis using propensity matching.

METHODS AND RESULTS

From 2012 to 2016, 1,306 patients at three German centres received either the ACURATE/ACURATE neo prosthesis (n=591) or the SAPIEN 3 prosthesis (n=715). Through nearest neighbour matching with exact allocation for access route and centre, pairs of 329 patients (250 transfemoral, 79 transapical) per group were determined. Patients were 81 years old on average and had a logistic EuroSCORE I of 19%. Predilatation and post-dilatation were more frequent in the ACURATE group (97.6% versus 52.1%, p<0.001 for predilatation and 40.4% versus 11.6%, p<0.001 for post-dilatation), but rapid pacing for implantation was used less frequently (37.1% versus 98.2%, p<0.001). More-than-mild aortic regurgitation at postoperative echocardiography was 12.0% for the ACURATE group and 3.1% for the SAPIEN group, p≤0.001). More-than-mild aortic regurgitation in the ACURATE group differed amongst the centres with 6.0% (3/50) in centre A, 34.1% (29/85) in centre B and 3.4% (6/181) in centre C. Patients in the ACURATE group less frequently had pacemaker implantation compared to the SAPIEN 3 group (11.9% versus 18.5%, p=0.020), 30-day mortality was 4.6% versus 2.1%, respectively, p=0.134, and one-year survival was 83.1% (95% CI: 77.6-87.4) versus 88.8% (95% CI: 84.0-92.2).

CONCLUSIONS

In this propensity score analysis, patients treated with the transapical ACURATE or transfemoral ACURATE neo prosthesis less frequently had pacemakers at 30 days but had more aortic regurgitation and lower one-year survival.

Safety and efficacy of a self-expanding versus a balloon-expandable bioprosthesis for transcatheter aortic valve replacement in patients with symptomatic severe aortic stenosis: a randomised non-inferiority trial

BACKGROUND

Transcatheter aortic valve replacement (TAVR) is the preferred treatment option for older patients with symptomatic severe aortic stenosis. Differences in the properties of available TAVR systems can affect clinical outcomes. Among patients undergoing TAVR, we compared the self-expanding ACURATE neo TAVR system with the balloon-expandable SAPIEN 3 TAVR system with regard to early safety and efficacy.

METHODS

In this randomised non-inferiority trial, patients (aged ≥75 years) undergoing transfemoral TAVR for treatment of symptomatic severe aortic stenosis, and who were deemed to be at increased surgical risk, were recruited at 20 tertiary heart valve centres in Germany, the Netherlands, Switzerland, and the UK. Participants were randomly assigned (1:1) to receive treatment with the ACURATE neo or the SAPIEN 3 with a computer-based randomly permuted block scheme, stratified by study centre and Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) category. The primary composite safety and efficacy endpoint comprised all-cause death, any stroke, life-threatening or disabling bleeding, major vascular complications, coronary artery obstruction requiring intervention, acute kidney injury (stage 2 or 3), rehospitalisation for valve-related symptoms or congestive heart failure, valve-related dysfunction requiring repeat procedure, moderate or severe prosthetic valve regurgitation, or prosthetic valve stenosis within 30 days of the procedure. Endpoint assessors were masked to treatment allocation. Non-inferiority of ACURATE neo compared with SAPIEN 3 was assessed in the intention-to-treat population on the basis of a risk-difference margin of 7·7% for the primary composite endpoint, with a one-sided α of 0·05. This trial is registered with ClinicalTrials.gov (number NCT03011346) and is ongoing but not recruiting.

FINDINGS

Between Feb 8, 2017, and Feb 2, 2019, up to 5132 patients were screened and 739 (mean age 82·8 years [SD 4·1]; median STS-PROM score 3·5% [IQR 2·6-5·0]) were enrolled. 30-day follow-up was available for 367 (99%) of 372 patients allocated to the ACURATE neo group, and 364 (99%) of 367 allocated to the SAPIEN 3 group. Within 30 days, the primary endpoint occurred in 87 (24%) patients in the ACURATE neo and in 60 (16%) in the SAPIEN 3 group; thus, non-inferiority of the ACURATE neo was not met (absolute risk difference 7·1% [upper 95% confidence limit 12·0%], p=0·42). Secondary analysis of the primary endpoint suggested superiority of the SAPIEN 3 device over the ACURATE neo device (95% CI for risk difference -1·3 to -12·9, p=0·0156). The ACURATE neo and SAPIEN 3 groups did not differ in incidence of all-cause death (nine patients [2%] vs three [1%]) and stroke (seven [2%] vs 11 [3%]); whereas acute kidney injury (11 [3%] vs three [1%]) and moderate or severe prosthetic aortic regurgitation (34 [9%] vs ten [3%]) were more common in the ACURATE neo group.

INTERPRETATION

TAVR with the self-expanding ACURATE neo did not meet non-inferiority compared to the balloon-expandable SAPIEN 3 device in terms of early safety and clinical efficacy outcomes. An early composite safety and efficacy endpoint was useful in discriminating the performance of different TAVR systems.

FUNDING

Boston Scientific (USA).

Performance and short-term outcomes of three different transcatheter aortic valve replacement devices in patients with aortic stenosis: A single-center experience

BACKGROUND

Data on whether different transcatheter aortic valve replacement (TAVR) devices and delivery approaches can achieve equally favorable outcomes when performed by a single heart team are scarce. We sought to compare the performance and short-term outcomes of three different TAVR devices-self-expanding Medtronic CoreValve (MCV), mechanically expanded Lotus valve, and balloon-expandable Edwards SAPIEN XT (SXT)-for the treatment of severe aortic stenosis (AS) in a single large-volume center in Taiwan.

METHODS

We retrospectively reviewed consecutive patients who underwent TAVR for the treatment of severe AS. Clinical outcomes were reported following Valve Academic Research Consortium 2 (VARC-2) criteria. The composite primary endpoint was combined all-cause mortality, myocardial infarction (MI), or disabling stroke within 180 days.

RESULTS

A total of 231 patients (MCV n=112, Lotus n=18, and SXT n=101) were included. The device and procedural success rates were similar among all three TAVR devices. At 30 days, there was no significant difference in all-cause mortality, cardiovascular mortality, periprocedural MI, stroke, major vascular complications, life-threatening bleeding, acute kidney injury (AKI, stage 2/3), or VARC-2 composite early safety endpoints. There was no difference among groups in the rate of primary endpoint within 180 days. Lack of procedural success, presence of acute coronary occlusion during TAVR, and presence of AKI (stage 3) after TAVR were independent predictors of adverse outcomes.

CONCLUSION

TAVR using MCV, Lotus, or SXT was associated with similar 30- and 180-day clinical outcomes. The presence of periprocedural complications was one of the main determinants of short-term adverse outcomes.

Pacemaker Implantation and Dependency After Transcatheter Aortic Valve Replacement in the REPRISE III Trial

Background

As transcatheter aortic valve replacement expands to younger and/or lower risk patients, the long‐term consequences of permanent pacemaker implantation are a concern. Pacemaker dependency and impact have not been methodically assessed in transcatheter aortic valve replacement trials. We report the incidence and predictors of pacemaker implantation and pacemaker dependency after transcatheter aortic valve replacement with the Lotus valve.

Methods and Results

A total of 912 patients with high/extreme surgical risk and symptomatic aortic stenosis were randomized 2:1 (Lotus:CoreValve) in REPRISE III (The Repositionable Percutaneous Replacement of Stenotic Aortic Valve through Implantation of Lotus Valve System—Randomized Clinical Evaluation) trial. Systematic assessment of pacemaker dependency was pre‐specified in the trial design. Pacemaker implantation within 30 days was more frequent with Lotus than CoreValve. By multivariable analysis, predictors of pacemaker implantation included baseline right bundle branch block and depth of implantation; diabetes mellitus was also a predictor with Lotus. No association between new pacemaker implantation and clinical outcomes was found. Pacemaker dependency was dynamic (30 days: 43%; 1 year: 50%) and not consistent for individual patients over time. Predictors of pacemaker dependency at 30 days included baseline right bundle branch block, female sex, and depth of implantation. No differences in mortality or stroke were found between patients who were pacemaker dependent or not at 30 days. Rehospitalization was higher in patients who were not pacemaker dependent versus patients without a pacemaker or those who were dependent.

Conclusions

Pacemaker implantation was not associated with adverse clinical outcomes. Most patients with a new pacemaker at 30 days were not dependent at 1 year. Mortality and stroke were similar between patients with or without pacemaker dependency and patients without a pacemaker.

Clinical Trial Registration

URL: https://www.clinicaltrials.gov/. Unique identifier NCT02202434.

Infective endocarditis after transcatheter aortic valve implantation: a nationwide study

AIMS

Transcatheter aortic valve implantation (TAVI), now a common procedure to treat high-risk patients with severe aortic stenosis, has rapidly been expanding into younger and lower-risk populations, creating a need to better understand long-term outcome after TAVI. The aim of the present investigation was to determine the incidence, risk factors for, clinical presentation of, and outcome after prosthetic valve endocarditis (PVE) in patients treated with TAVI in a nationwide study.

METHODS AND RESULTS

Three registries were used: a national TAVI registry, a national diagnosis registry, and a national infective endocarditis registry. Combining these registries made it possible to perform a nationwide, all-comers study with independent and validated reporting of PVE in 4336 patients between 2008 and mid-2018. The risk for PVE after TAVI was 1.4% (95% confidence interval 1.0-1.8%) the first year and 0.8% (0.6-1.1%) per year thereafter. One-year survival after PVE diagnosis was 58% (49-68%), and 5-year survival was 29% (17-41%). Body surface area, estimated glomerular filtration rate <30 mL/min/1.73 m2, critical pre-operative state, mean pre-procedural valve gradient, amount of contrast dye used, transapical access, and atrial fibrillation were identified as independent risk factors for PVE. Staphylococcus aureus was more common in early (<1 year) PVE. Infection with S. aureus, root abscess, late PVE, and non-community acquisition was associated with higher 6-month mortality.

CONCLUSION

The incidence of PVE was similar to that of surgical bioprostheses. Compromised renal function was a strong risk factor for developing PVE. In the context of PVE, TAVI seems to be a safe option for patients.

CLINICAL TRIAL REGISTRATION

NCT03768180 (http://clinicaltrials.gov/).

Transcatheter Aortic Valve Replacement with the Lotus Valve: Concept and Current State of the Data

Multiple transcatheter heart valve iterations have created an interesting range of options with which to perform transcatheter aortic valve replacement. The Lotus valve has several attractive features. The ability to eradicate even mild paravalvular leak mirrors the outcomes of surgical aortic valve replacement. New design iterations of the Lotus valve and refined sizing algorithms may help mitigate the need for permanent pacemaker implantation and consolidate its best-in-class results in terms of paravalvular leak. Ongoing trials should help define the safety and efficacy of the Lotus transcatheter heart valve in contemporary practice.

Predictors and Risk Calculator of Early Unplanned Hospital Readmission Following Contemporary Self-Expanding Transcatheter Aortic Valve Replacement from the STS/ACC TVT Registry

BACKGROUND

Predictors of hospital readmissions and tools to predict readmissions after TAVR are scarce. Our objective was to identify predictors of early hospital readmission following TAVR in contemporary clinical practice and develop a risk calculator.

METHODS

Patients with a contemporary self-expanding TAVR between 2015 and 2017 in the STS/ACC/TVT Registry™ database were included. Patients were divided into a derivation and validation cohort (2:1). A risk score was calculated using the derivation cohort based on multivariable predictors of 30-day unplanned readmissions and applied to the validation cohort.

RESULTS

A total of 10,345 TAVR patients at 350 centers were included. Unplanned 30-day hospital readmission was 9.2%. Patients with an early readmission had higher 30-day rates for mortality (2.3% vs. 0.8%, p ≪ 0.001), stroke (4.1% vs. 2.7% p = 0.009), major vascular complications (2.0% vs. 1.0%, p = 0.003) and new pacemaker implantation (25.7% vs. 18.6%, p ≪ 0.001). Multivariable predictors of 30-day readmission included diabetes, atrial fibrillation, advanced heart failure symptoms, home oxygen, decreased 5-m gait speed or the inability to walk, serum creatinine ≫1.6 mg/dL, index hospitalization length of stay ≫5 days, major vascular complication and ≥ moderate post-procedure aortic or mitral valve regurgitation. Based on these predictors, we stratified 30-day readmission risk into low-, moderate- and high-risk subsets. There was a 2.5× difference in readmission rates between the low- (5.8%) and high-risk subsets (14.6%).

CONCLUSION

We stratified the risk of early hospital readmission after TAVR based on a simple scoring system. This score may improve discharge planning centered on the individual's readmission risk.

SUMMARY

Unplanned readmissions in the United States are prevalent and costly accounting for $41.3 billion in annual hospital payments and are associated with adverse clinical outcomes. We found that diabetes, atrial fibrillation, advanced heart failure symptoms, home oxygen, frailty, acute kidney injury, prolonged hospitalization, major vascular complications, and moderate or worse post-procedure aortic or mitral valve regurgitation predicted of 30-day readmission following self-expanding TAVR. This information may improve discharge planning centered on each patient's readmission risk.

Minimally invasive surgical versus transcatheter aortic valve replacement: A multicenter study

OBJECTIVES

Treatment of aortic valve stenosis is evolving, indications for transcatheter approach (TAVI) have increased but also surgical valve replacement has changed with the use of minimally invasive approaches. Comparisons between TAVI and surgery have rarely been done with minimally invasive techniques (mini-SAVR) in the surgical arm. Aim of the present study is to compare mini-SAVR and TAVI in a multicenter recent cohort.

METHODS

Evaluated were 2904 patients undergone mini-SAVR (2407) or TAVI (497) in 10 different centers in the period 2011-2016. The Heart Team approved treatment for complex cases. The primary outcome is the incidence of 30-day mortality following mini-SAVR and TAVI. Secondary outcomes are the occurrence of major complications following both procedures. Propensity matched comparisons was performed based on multivariable logistic regression model.

RESULTS

In the overall population TAVI patients had increased surgical risk (median EuroSCORE II 3.3% vs. 1.7%, p ≤ 0.001) and 30-day mortality was higher (1.5% and 2.8% in mini-SAVR and TAVI respectively, p = 0.048). Propensity score identified 386 patients per group with similar baseline profile (median EuroSCORE II ~3.0%). There was no difference in 30-day mortality (3.4% in mini-SAVR and 2.3% in TAVI; p = 0.396) and stroke, surgical patients had more blood transfusion, kidney dysfunction and required longer ICU and hospital length of stay while TAVI patients had more permanent pace maker insertion.

CONCLUSIONS

Mini-SAVR and TAVI are both safe and effective to treat aortic stenosis in elderly patients with comorbidities. A joint evaluation by the heart-team is essential to direct patients to the proper approach.

Why should we extend transcatheter aortic valve implantation to low-risk patients? A comprehensive review

Within the past decade, transcatheter aortic valve implantation (TAVI) has become established as the optimal treatment option for elderly, inoperable and high-risk patients with severe aortic stenosis, and is now recommended by international guidelines. Randomized controlled trials have demonstrated the non-inferiority of TAVI to open surgery in intermediate-risk patients and, most recently, in low-risk patients. Further randomized controlled trials are underway, but existing studies have already provided reassuring data in this cohort, and TAVI is offered routinely to younger and lower-risk patients in numerous centers. Improvements in the design of devices and delivery systems, accompanied by increased operator experience, have dramatically improved the safety of the procedure, and further expansion into low-risk groups seems inevitable once concerns about valve durability and device cost have been addressed. In this article, we provide a review of the existing literature, and estimate the clinical impact of TAVI in low-risk patients. Abbreviated title: Why should we extend TAVI to low-risk patients?

Anatomical predictors of conduction damage after transcatheter implantation of the aortic valve

Objective

Conduction damage following transcatheter aortic valve implantation (TAVI) remains common. Anatomical risk factors remain elusive. We assessed the impact of variability in the dimensions of the membranous septum and position of the aortic root on the occurrence of conduction damage following TAVI.

Methods

The dimensions of the membranous septum, the rotational position of the aortic root correlating to variability in the central fibrous body width, and wedging of the aortic root were assessed on pre-TAVI CT datasets. The depth of implantation was measured from the final aortic angiogram. The variables were compared with the occurrence of both permanent pacemaker insertion (PPI) and left bundle branch block (LBBB) following TAVI.

Results

Of 200 patients who met inclusion criteria (mean age = 81 years ± 7.7, 49% men), 20.5 % underwent PPI after TAVI. New LBBB occurred in 23.5%, 21.3 % of whom required PPI. Preprocedural right bundle branch block (OR = 7.00; CI 3.13 to 15.64), valve type (OR=2.35; CI 1.13 to 4.87), depth of implantation (OR=1.62; CI 1.01 to 2.61) and the difference between depth of implantation and the distance from the virtual basal ring to the inferior margin of the membranous septum (OR=0.61; CI 0.38 to 0.99) were all associated with PPI, with similar associations with LBBB. No gross anatomical variable alone was associated with conduction damage.

Conclusions

Gross anatomical variation of the aortic root and its underlying support, including the membranous septum, were not associated with the occurrence of either PPI or new LBBB. Procedural characteristics associated with these adverse outcomes suggest that the depth of implantation and radial force of the bioprosthesis, regardless of gross anatomical variability, increase the risk for conduction damage.

The evolution of device technology in transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) has rapidly evolved and changed the landscape of structural interventional cardiology. Advances in transcatheter heart valve (THV) prostheses and TAVI-enabling devices have simplified the procedure, reduced the risk of complications, improved short- and long-term outcomes and broadened the applications of TAVI, not only in challenging patients and complex anatomies but also in intermediate-risk or even in low-risk patients, where surgical valve replacement constitutes an effective and well-established therapy. In this review article, we provide an overview of the developments in TAVI devices which have played a vital role in TAVI evolution: we describe the prostheses that failed to reach clinical practice, we present the characteristics of the first valves that were tested in the clinical arena, we summarise the evidence from the first studies that highlighted the potential but also the limitations of TAVI, and we present the advanced next-generation THV prostheses that have an improved performance and safety profile.

Impact of valvular resistance on aortic regurgitation after transcatheter aortic valve replacement according to the type of prosthesis

BACKGROUND

The impact of aortic valvular resistance (VR) on the degree of post-transcatheter aortic valve replacement (TAVR) aortic regurgitation (AR) remains unclear. The objective of the study was to investigate the relationship between VR and paravalvular AR after TAVR.

METHODS

Between August 2007 and December 2015, 708 TAVR patients had sufficient data to calculate VR before the intervention and were eligible for the present analysis. The patient population was dichotomized according to VR. The association between VR and post-TAVR AR was separately assessed by prosthesis type.

RESULTS

Among patients with low VR (LVR; < 238 dynes/cm⁵), 176 (49.7%) patients were treated with balloon-expandable (BE) valves and 178 (51.3%) patients with self-expandable (SE) transcatheter valves. Among patients with high VR (HVR ≥ 238), 147 (41.5%) and 207 (68.5%) patients received BE and SE, respectively. Baseline characteristics were similar in both groups irrespective of the type of valve. Patients with HVR had a 2.5-fold risk of ≥ moderate post-TAVR AR compared to patients with LVR. Both, HVR (HR_adj 2.45, 95% CI 1.33-4.51) and the use of SE (HR_adj 3.11, 95% CI 1.66-5.82), emerged as independent predictors of ≥ moderate post-TAVR AR. Moderate or greater post-AR was consistently predicted in patients treated with SE (HR_adj 2.42, 95% CI 1.22-4.80) irrespective of the level of VR.

CONCLUSIONS

HVR is associated with a nearly 2.5-fold increased risk of moderate or greater post-TAVR AR and is an independent predictor of post-TAVR AR.

Clinical outcomes of the Lotus Valve in patients with bicuspid aortic valve stenosis: An analysis from the RESPOND study

AIMS

Patients with bicuspid valves represent a challenging anatomical subgroup for transcatheter aortic valve implantation (TAVI). This analysis evaluated the clinical outcomes of the fully repositionable and retrievable Lotus Valve System in patients with bicuspid aortic valves enrolled in the RESPOND post-market registry.

METHODS AND RESULTS

The prospective, open-label RESPOND study enrolled 1,014 patients at 41 centers in Europe, New Zealand, and Latin America, 31 (3.1%) of whom had bicuspid aortic valves. The mean age in the bicuspid patient cohort was 76.4 years, 64.5% were male, and the baseline STS score was 6.0 ± 10.2. Procedural success was 100%, with no cases of malpositioning, valve migration, embolization, or valve-in-valve. Repositioning was attempted in 10 cases (32.3%). There was one death (3.2%) and one stroke (3.2%) at 30-day follow-up. Mean AV gradient was reduced from 48.7 ± 17.0 mmHg at baseline to 11.8 ± 5.1 mmHg at hospital discharge (P < 0.001); mean effective orifice area (EOA) was increased from 0.6 ± 0.2 cm² to 1.7 ± 0.4 cm² (P < 0.001). There were no cases of moderate or severe paravalvular leak (PVL) adjudicated by the core laboratory; four subjects (13.8%) had mild PVL, 5 (17.2%) had trace PVL. The rate of pacemaker (PM) implantation for PM-naïve patients was 22.2% (6/27).

CONCLUSIONS

Data from the RESPOND registry demonstrate good clinical and echocardiographic outcomes up to 1 year postimplantation in patients with bicuspid aortic valves using the repositionable Lotus Valve.

Prospective Evaluation for Hypoattenuated Leaflet Thickening Following Transcatheter Aortic Valve Implantation

Prospective investigations for the frequency of hypoattenuated leaflet thickening (HALT) and its clinical implications in transcatheter aortic valve implantation (TAVI) patients are limited. We initiated a prospective screening program of TAVI patients for HALT beginning in July 2015. Eligible patients were evaluated with gated, contrast-enhanced multidetector computed tomography within 30 days of TAVI, and examined for HALT and clinical outcomes. During the study period, 287 patients (81 ± 8 years; 53% men) who underwent TAVI with commercially approved devices were examined. Overall, 26 patients (9.1%) had occurrence of HALT, and only one of these patients had detectable hemodynamic changes on echocardiography at diagnosis. Notably, 9 of 26 HALT patients had been receiving warfarin, however, the HALT patients more often had subtherapeutic international normalized ratio whereas using warfarin than patients without HALT on index multidetector computed tomography imaging (p = 0.01). Patients who developed HALT had lower baseline aortic gradient, valvuloarterial impedance, and peak aortic velocity, and more commonly had been treated with balloon-expandable valves (73% of all HALT cases) with a higher incidence among those who received larger prostheses. All patients with HALT were placed on anticoagulation at diagnosis, and valvular function remained unchanged at follow-up. Two patients with HALT (7.7%) experienced ischemic stroke. A statistical trend for more major adverse clinical events was present in HALT patients. In conclusion, HALT was detected in 9% of TAVI cases in this prospective observational cohort, with a greater frequency in patients with large, balloon-expandable prostheses. Prospective screening may be considered as early HALT is reversible by timely therapeutic anticoagulation.

Maturation from CoreValve® to Evolut Pro®: a clinical overview

The only curative treatment of aortic stenosis is through surgical or transcatheter aortic valve replacement. Transcatheter aortic valve implantation has evolved from its first in human experience in 2002 and matured to the treatment of first choice of symptomatic severe aortic stenosis in elderly patients with an elevated operative risk. The self-expanding CoreValve^® bioprosthesis has been on the forefront of this growing transcatheter aortic valve implantation experience. Over the last decade, various device iterations resulted in the current Evolut PRO^® self-expanding valve platform with reduced profile, repositioning/retrievable features and porcine pericardial wrap. Herein we provide a critical appraisal of the consecutive device iterations and highlight the clinical foundation for the use of the self-expanding CoreValve^® /Evolut platforms in current clinical practice.