Hydrodynamic Performance of the Medtronic CoreValve and the Edwards SAPIEN XT Transcatheter Heart Valve in Surgical Bioprostheses: An In Vitro Valve-in-Valve Model

Supra-Annular Self-Expanding Versus Balloon-Expandable Valves for Valve-in-Valve Transcatheter Aortic Valve Replacement

Self-expanding (SE) and balloon-expandable (BE) transcatheter heart valves (THVs) have not been extensively studied in valve-in-valve (ViV) transcatheter aortic valve replacement (TAVR). We compared outcomes of supra-annular SE and BE THVs used for ViV-TAVR through a retrospective analysis of institutional data (2013 to 2023) including all patients who underwent ViV-TAVR (TAVR in previous surgical aortic valve replacement). Unmatched and propensity-matched (1:1) comparisons of clinical and echocardiographic outcomes were undertaken in SE and BE THVs along with Kaplan-Meier survival analysis. A total of 315 patients who underwent ViV-TAVR were included, of whom 73% received an SE THV. Median age was 77 years, and women comprised 42.5% of the population. Propensity-score matching (1:1) yielded 81 matched pairs. Implanted aortic valve size was comparable in the groups (23 mm [23 to 26] vs 23 mm [23 to 26], p = 0.457). At 30 days after ViV-TAVR, the SE group had a lower mean aortic valve gradient (14 mm Hg [11 to 18] vs 17.5 mm Hg [13 to 25], p = 0.007). A greater number of patients with BE THV had severe prosthesis-patient mismatch (16% vs 6.2%, p = 0.04). At 1-year follow-up, the SE THV group had a lower aortic valve gradient (14.0 mm Hg [9.6 to 19] vs 17 mm Hg [13 to 25], p = 0.04) than that of the BE THV group; 30-day mortality was 2.7%, whereas 1-year mortality was 7.5% and comparable in the groups. Survival and stroke incidence were similar in the groups up to 5 years. In conclusion, SE and BE THVs had comparable survival after ViV-TAVR. The higher residual aortic valve gradients in BE THVs are likely due to valve design and warrant long-term evaluation for potential structural valve degeneration.

Hemodynamic outcomes after valve-in-valve transcatheter aortic valve replacement: a single-center experience

Background

Valve-in-valve transcatheter aortic valve replacement (ViV-TAVR) has emerged as a safe, effective alternative to redo aortic valve surgery in high-risk patients with degenerated surgical bioprosthetic valves. However, ViV-TAVR has been associated high postprocedural valvular gradients, compared with TAVR for native-valve aortic stenosis.

Methods

We performed a retrospective study of all patients who underwent ViV-TAVR for a degenerated aortic valve bioprosthesis between January 1, 2013 and March 31, 2019 at our center. The primary outcome was postprocedural mean aortic valve gradient. Outcomes were compared across surgical valve type (stented versus stentless), surgical valve internal diameter (≤19 versus >19 mm), and transcatheter aortic valve type (self-expanding vs. balloon-expandable).

Results

Overall, 89 patients underwent ViV-TAVR. Mean age was 69.0±12.6 years, 61% were male, and median Society of Thoracic Surgeons Predicted Risk of Mortality score was 5.4 [interquartile range, 3.2-8.5]. Bioprosthesis mode of failure was stenotic (58% of patients), regurgitant (24%), or mixed (18%). The surgical valve was stented in 75% of patients and stentless in 25%. The surgical valve's internal diameter was ≤19 mm in 45% of cases. A balloon-expandable transcatheter valve was used in 53% of procedures. Baseline aortic valve area and mean gradients were 0.87±0.31 cm² and 36±18 mmHg, respectively. These improved after ViV-TAVR to 1.38±0.55 cm² and 18±11 mmHg at a median outpatient follow-up of 331 [67-394] days. Higher postprocedural mean gradients were associated with surgical valves having an internal diameter ≤19 mm (24±13 versus 16±8, P=0.002) and with stented surgical valves (22±11 versus 12±6, P<0.001).

Conclusions

ViV-TAVR is an effective option for treating degenerated surgical aortic bioprostheses, with acceptable hemodynamic outcomes. Small surgical valves and stented surgical valves are associated with higher postprocedural gradients.

Bioengineered percutaneous heart valves for transcatheter aortic valve replacement: a comparative evaluation of decellularised bovine and porcine pericardia

Glutaraldehyde-treated, surgical bioprosthetic heart valves undergo structural degeneration within 10-15 years of implantation. Analogous preliminary results were disclosed for percutaneous heart valves (PHVs) realized with similarly-treated tissues. To improve long-term performance, decellularised scaffolds can be proposed as alternative fabricating biomaterials. The aim of this study was to evaluate whether bovine and porcine decellularised pericardia could be utilised to manufacture bioengineered percutaneous heart valves (bioPHVs) with adequate hydrodynamic performance and leaflet resistance to crimping damage. BioPHVs were fabricated by mounting acellular pericardia onto commercial stents. Independently from the pericardial species used for valve fabrication, bioPHVs satisfied the minimum hydrodynamic performance criteria set by ISO 5840-3 standards and were able to withstand a large spectrum of cardiac output conditions, also during extreme backpressure, without severe regurgitation, especially in the case of the porcine group. No macroscopic or microscopic leaflet damage was detected following bioPHV crimping. Bovine and porcine decellularized pericardia are both suitable alternatives to glutaraldehyde-treated tissues. Between the two types of pericardial species tested, the porcine tissue scaffold might be preferable to fabricate advanced PHV replacements for long-term performance. CONDENSED ABSTRACT: Current percutaneous heart valve replacements are formulated with glutaraldehyde-treated animal tissues, prone to structural degeneration. In order to improve long-term performance, bovine and porcine decellularised pericardia were utilised to manufacture bioengineered replacements, which demonstrated adequate hydrodynamic behaviour and resistance to crimping without leaflet architectural alteration.

Balloon-expandable versus self-expanding transcatheter aortic valve replacement for bioprosthetic dysfunction: A systematic review and meta-analysis

BACKGROUND

Transcatheter aortic valve-in-valve (VIV) procedure is a safe alternative to conventional reoperation for bioprosthetic dysfunction. Balloon-expandable valve (BEV) and self-expanding valve (SEV) are the 2 major types of devices used. Evidence regarding the comparison of the 2 valves remains scarce.

METHODS

A systematic review and meta-analysis was conducted to compare the outcomes of BEV and SEV in transcatheter VIV for aortic bioprostheses dysfunction. A computerized search of Medline, PubMed, Embase, and Cochrane databases was performed. English-language journal articles reporting SEV or BEV outcomes of at least 10 patients were included.

RESULTS

In total, 27 studies were included, with 2,269 and 1,671 patients in the BEV and SEV groups, respectively. Rates of 30-day mortality and stroke did not differ significantly between the 2 groups. However, BEV was associated with significantly lower rates of postprocedural permanent pacemaker implantation (3.8% vs. 12%; P < 0.001). Regarding echocardiographic parameters, SEV was associated with larger postprocedural effective orifice area at 30 days (1.53 cm2 vs. 1.23 cm2; P < 0.001) and 1 year (1.55 cm2 vs. 1.22 cm2; P < 0.001).

CONCLUSIONS

For patients who underwent transcatheter aortic VIV, SEV was associated with larger postprocedural effective orifice area but higher rates of permanent pacemaker implantation. These findings provide valuable information for optimizing device selection for transcatheter aortic VIV.

Hemodynamic comparison of CoreValve and SAPIEN-XT TAVI valves in Japanese patients

Transcatheter aortic valve implantation (TAVI) is a viable treatment option for high-risk patients with severe aortic stenosis. In Japan, TAVI can be performed using first-generation self-expandable Medtronic CoreValve or balloon-expandable Edwards SAPIEN-XT from 2012. Since the durability and hemodynamic outcomes after transcatheter heart valve (THV) implantation in Japanese patients have not been clearly elucidated, we assessed serial changes in post-TAVI THV performances over a-3-year period by transthoracic echocardiography (TTE). From January 2012 to September 2014, among 83 patients with severe aortic stenosis, 26 underwent TAVI with CoreValve and 57 underwent TAVI with SAPIEN-XT. We assessed the serial changes in first post-implant (FPI) and 3-year post procedure THV hemodynamics by TTE. Valve performance was evaluated by serial assessment of aortic valve mean pressure gradient (PG) and aortic valve area (AVA) assessments. Three-year clinical outcomes were compared between the patients with CoreValve and those with SAPIEN-XT. Seventeen patients with CoreValve and 34 patients with SAPIEN-XT had FPI and 3-year TTEs. The AVA decreased significantly from FPI to 3-year follow-up among patients with SAPIEN-XT, but not among patients with CoreValve. The mean aortic PG decreased significantly from FPI to the 3-year follow-up point among patients with CoreValve; however, it was not significantly different from those with SAPIEN-XT. The absolute change in mean PG from FPI to the 3-year follow-up point decreased significantly among those with CoreValve compared to those with SAPIEN-XT. Clinical outcomes after TAVI were similar for both devices at 3-years after TAVI. In this study, long-term clinical outcomes for CoreValve and SAPIEN XT were similar. The 3-year THV performance of both devices was maintained after TAVI. Serial change in mean aortic PGs for CoreValve decreases significantly from FPI to the 3-year follow-up point compared to that for SAPIEN-XT.

First-in-human implantation of a novel self-expanding supra-annular transcatheter heart valve for transcatheter aortic valve implantation inside a small degenerated aortic surgical bioprosthesis

With next-generation valves such as the ALLEGRA valve from NewValve Technologies (NVT), Hechingen Germany, there is a very likely treatment expansion for patients with aortic valve disease. Besides treatment of native valvular aortic stenosis with the ALLEGRA valve, the special implant mechanism seems to be an appealing concept for patients with degenerated surgical bioprostheses. We report the first case of a transfemoral implantation in small degenerated surgical bioprosthesis of a 76-year-old woman.

Outcomes of Self-Expanding vs. Balloon-Expandable Transcatheter Heart Valves for the Treatment of Degenerated Aortic Surgical Bioprostheses - A Propensity Score-Matched Comparison

BACKGROUND

Transcatheter aortic valve-in-valve (VIV) replacement within failed bioprosthetic surgical aortic valves is a feasible therapeutic option. However, data comparing the hemodynamic and clinical outcomes of VIV replacement with supra-annular self-expanding and balloon-expandable transcatheter heart valves (THV) are limited.

METHODS AND RESULTS

Outcomes of 40 and 95 patients treated with supra-annular self-expanding and balloon-expandable THV, respectively, were compared after propensity score matching, which yielded 37 pairs of patients with similar baseline characteristics. Hemodynamic and clinical outcomes were analyzed. Postprocedural mean gradient was significantly lower in the self-expanding THV group than in the balloon-expandable THV group (12.1±6.1 mmHg vs. 19.0±7.3 mmHg, P<0.001). The incidence of at least mild postprocedural aortic regurgitation (AR) was comparable between the self-expanding and balloon-expandable THV groups (21.6% vs. 10.8%, P=0.39). In the self-expanding THV group, the new-generation THV showed a trend towards a lower incidence of at least mild AR compared with the early-generation THV (12.5% vs. 38.5%, P=0.07). A similar trend was observed in the balloon-expandable THV group (4.2% vs. 23.1%, P=0.08). There was no significant difference between the self-expanding and balloon-expandable THV groups in the cumulative 2-year all-cause mortality rates (22.4% vs. 43.4%, log-rank P=0.26).

CONCLUSIONS

The supra-annular self-expanding THV was associated with a lower postprocedural mean gradient compared with balloon-expandable THV in patients undergoing aortic VIV replacement.

Transcatheter Aortic Valve-in-Valve Procedure in Patients with Bioprosthetic Structural Valve Deterioration

Surgical aortic valve replacement is the gold standard procedure to treat patients with severe, symptomatic aortic valve stenosis or insufficiency. Bioprosthetic valves are used for surgical aortic valve replacement with a much greater prevalence than mechanical valves. However, bioprosthetic valves may fail over time because of structural valve deterioration; this often requires intervention due to severe bioprosthetic valve stenosis or regurgitation or a combination of both. In select patients, transcatheter aortic valve replacement is an alternative to surgical aortic valve replacement. Transcatheter valve-in-valve (ViV) replacement is performed by implanting a transcatheter heart valve within a failing bioprosthetic valve. The transcatheter ViV operation is a less invasive procedure compared with reoperative surgical aortic valve replacement, but it has been associated with specific complications and requires extensive preoperative work-up and planning by the heart team. Data from experimental studies and analyses of results from clinical procedures have led to strategies to improve outcomes of these procedures. The type, size, and implant position of the transcatheter valve can be optimized for individual patients with knowledge of detailed dimensions of the surgical valve and radiographic and echocardiographic measurements of the patient's anatomy. Understanding the complexities of the ViV procedure can lead surgeons to make choices during the original surgical valve implantation that can make a future ViV operation more technically feasible years before it is required.

Matched comparison of next- and early-generation balloon-expandable transcatheter heart valve implantations in failed surgical aortic bioprostheses

AIMS

Transcatheter valve-in-valve implantation (VinV) is established for the treatment of degenerated surgical bioprostheses in patients at high operative risk. Our aim was to report on the first large assessment of VinV with next-generation balloon-expandable transcatheter heart valves.

METHODS AND RESULTS

After SAPIEN XT or SAPIEN 3 VinV, 514 patients were analysed using an inverse probability of treatment weighting. Standardised clinical and haemodynamic outcomes were compared, and core laboratory evaluation of implantation depth was performed. Thirty-day all-cause mortality was 0.6% and 3.5% for SAPIEN 3 and SAPIEN XT (p=0.077). Residual transprosthetic gradient ≥20 mmHg was observed in 38.3% (SAPIEN 3) and 35.7% (SAPIEN XT) of patients (p=0.627) with increased rates in small bioprostheses (≤21 mm true ID). In SAPIEN 3 VinV, low implantation depth >20% THV stent frame length was associated with a higher rate of elevated transaortic gradients (p=0.048). Similarly, an implantation depth >5 mm was linked to more pacemaker implantations (p=0.01). Overall, a trend towards higher pacemaker implantation rates was observed after SAPIEN 3 VinV (6% vs. 2.5% in SAPIEN XT, p=0.071).

CONCLUSIONS

Transcatheter aortic VinV with the balloon-expandable SAPIEN XT or SAPIEN 3 was similarly safe and effective. However, residual stenosis remains a concern, particularly in smaller bioprostheses and with increasing implantation depth.

Optimizing hemodynamics of transcatheter aortic valve-in-valve implantation in 19-mm surgical aortic prostheses

OBJECTIVE

To demonstrate the feasibility of achieving good hemodynamic results with valve-in-valve transcatheter aortic valve replacement (ViV TAVR) for degenerated 19 mm surgical bioprosthetic valves.

BACKGROUND

Considerable controversy exists regarding ViV TAVR within 19mm surgical prostheses due to concerns of elevated valve gradients and mortality.

METHODS

Among all patient undergoing ViV TAVR between 7/2016 and 4/2017 for symptomatic severe bioprosthetic aortic stenosis (AS), five had a 19 mm surgical valve in place and were included in this publication. None of the patients had patient-prosthesis mismatch. Aggressive post-dilation was performed in four out of five cases using a special technique we describe below.

RESULTS

In all cases, mean aortic valve (AV) gradients significantly improved post-ViV TAVR, particularly after post-dilation. Interestingly, high pressure post-dilation of the ViV resulted in an increase in the diameter of surgical valve stent frame dimensions in nearly all patients who underwent post-dilation.

CONCLUSIONS

Good hemodynamic outcome is possible with aggressive post-dilation in patients with 19 mm failed surgical bioprostheses. High-risk patients with 19 mm failed surgical prostheses who do not otherwise have viable surgical options should be considered for ViV TAVR.

Valve-in-valve outcome: design impact of a pre-existing bioprosthesis on the hydrodynamics of an Edwards Sapien XT valve

Objectives

Bioprosthetic aortic heart valves are increasingly implanted in younger patients. Therefore, a strategy for potential valve failure should be developed before implanting the 'first valve'. The goal of this in vitro study was to provide insight into the effects of the design of a bioprosthesis on a valve-in-valve implanted Sapien XT valve.

Methods

The hydrodynamic performance of a 23-mm Sapien XT valve implanted in Vascutek Aspire, Edwards Perimount, Medtronic Mosaic and St. Jude Medical Trifecta heart valves was investigated in a left heart simulator. In addition to the hydrodynamic results, the leaflet dynamics were analysed in high-speed video recordings of the tests.

Results

All valve-in-valve combinations in this study fulfilled the minimum acceptance criteria defined by relevant approval standards (e.g. ISO 5840) but displayed significant differences in their performances. Small inner diameters of the bioprostheses were associated with increased mean pressure gradients, decreased effective orifice areas and geometric opening areas as well as with pin-wheeling and uneven leaflet motion. In addition, implantation in bioprostheses with internally mounted leaflets was associated with lower paravalvular leakage.

Conclusions

The results of this study suggest that a surgical bioprosthesis with a large inner diameter and internally mounted leaflets improves the heamodynamics and potentially the durability of a valve-in-valve combination. These results should give the attending physicians critical information to consider when deciding on a bioprosthesis for younger patients.

Matched Comparison of Self-Expanding Transcatheter Heart Valves for the Treatment of Failed Aortic Surgical Bioprosthesis

Background—

Transcatheter valve-in-valve implantation is an established therapy for high-risk patients with failed surgical aortic bioprosthesis. There are limited data comparing outcomes of valve-in-valve implantation using different transcatheter heart valves (THV).

Methods and Results—

Patients included in the Valve-in-Valve International Data registry (VIVID) and treated with self-expanding THV devices were analyzed using centralized core laboratory blinded to clinical events. St. Jude Medical Portico versus Medtronic CoreValve were compared in a 1:2 fashion after propensity score matching. A total of 162 patients, Portico- (n=54) and CoreValve- (n=108) based valve-in-valve procedures comprised the study population with no significant difference in baseline characteristics (age, 79±8.2 years; 60% women; mean STS [Society of Thoracic Surgery] score 8.1±5.5%). Postimplantation, CoreValve was associated with a larger effective orifice area (1.67 versus 1.31 cm 2 ; P =0.001), lower mean gradient (14±7.5 versus 17±7.5 mm Hg; P =0.02), and lower core laboratory–adjudicated moderate-to-severe aortic insufficiency (4.2% versus 13.7%; P =0.04), compared with Portico. Procedural complications including THV malpositioning, second THV requirement, or coronary obstruction were not significantly different between the 2 groups. Survival and stroke rates at 30 days were similar, but overall mortality at 1 year was higher among patients treated with Portico compared with CoreValve (22.6% versus 9.1%; P =0.03).

Conclusions—

In this first matched comparison of THVs for valve-in-valve implantations, Portico and CoreValve demonstrated differences in postprocedural hemodynamics and long-term clinical outcomes. Although this could be related to THV design characteristics, the impact of other procedural factors cannot be excluded and require further evaluation.

On the Mechanics of Transcatheter Aortic Valve Replacement

Transcatheter aortic valves (TAVs) represent the latest advances in prosthetic heart valve technology. TAVs are truly transformational as they bring the benefit of heart valve replacement to patients that would otherwise not be operated on. Nevertheless, like any new device technology, the high expectations are dampened with growing concerns arising from frequent complications that develop in patients, indicating that the technology is far from being mature. Some of the most common complications that plague current TAV devices include malpositioning, crimp-induced leaflet damage, paravalvular leak, thrombosis, conduction abnormalities and prosthesis-patient mismatch. In this article, we provide an in-depth review of the current state-of-the-art pertaining the mechanics of TAVs while highlighting various studies guiding clinicians, regulatory agencies, and next-generation device designers.

Transcatheter Replacement of Failed Bioprosthetic Valves

Background—

Transcatheter valve implantation inside failed bioprosthetic surgical valves (valve-in-valve [ViV]) may offer an advantage over reoperation. Supra-annular transcatheter valve position may be advantageous in achieving better hemodynamics after ViV. Our objective was to define targets for implantation that would improve hemodynamics after ViV.

Methods and Results—

Cases from the Valve-in-Valve International Data (VIVID) registry were analyzed using centralized core laboratory assessment blinded to clinical events. Multivariate analysis was performed to identify independent predictors of elevated postprocedural gradients (mean ≥20 mm Hg). Optimal implantation depths were defined by receiver operating characteristic curve. A total of 292 consecutive patients (age, 78.9±8.7 years; 60.3% male; 157 CoreValve Evolut and 135 Sapien XT) were evaluated. High implantation was associated with significantly lower rates of elevated gradients in comparison with low implantation (CoreValve Evolut, 15% versus 34.2%; P =0.03 and Sapien XT, 18.5% versus 43.5%; P =0.03, respectively). Optimal implantation depths were defined: CoreValve Evolut, 0 to 5 mm; Sapien XT, 0 to 2 mm (0–10% frame height); sensitivities, 91.3% and 88.5%, respectively. The strongest independent correlate for elevated gradients after ViV was device position (high: odds ratio, 0.22; confidence interval, 0.1–0.52; P =0.001), in addition to type of device used (CoreValve Evolut: odds ratio, 0.5; confidence interval, 0.28–0.88; P =0.02) and surgical valve mechanism of failure (stenosis/mixed baseline failure: odds ratio, 3.12; confidence interval, 1.51–6.45; P =0.002).

Conclusions—

High implantation inside failed bioprosthetic valves is a strong independent correlate of lower postprocedural gradients in both self- and balloon-expandable transcatheter valves. These clinical evaluations support specific implantation targets to optimize hemodynamics after ViV.