Valve-in-Valve Transcatheter Aortic Valve Replacement and Bioprosthetic Valve Fracture Comparing Different Transcatheter Heart Valve Designs: An Ex Vivo Bench Study

In Vitro Comparison of a Closed and Semi-closed Leaflet Design for Adult and Pediatric Transcatheter Heart Valves

Transcatheter heart valve replacements (TVR) are mostly designed in a closed position (c) with leaflets coaptating. However, recent literature suggests fabricating valves in semi-closed (sc) position to minimize pinwheeling. With about 100,000 children in need of a new pulmonary valve each year worldwide, this study evaluates both geometrical approaches in adult as well as pediatric size and condition. Three valves of each geometry were fabricated in adult (30 mm) and pediatric (15 mm) size, using porcine pericardium. To evaluate performance, the mean transvalvular pressure gradient (TPG), effective orifice area (EOA), and regurgitation fraction (RF) were determined in three different annulus geometries (circular, elliptic, and tilted). For both adult-sized valve geometries, the TPG (TPGC = 2.326 ± 0.115 mmHg; TPGSC = 1.848 ± 0.175 mmHg)* and EOA (EOAC = 3.69 ± 0.255 cm2; EOASC = 3.565 ± 0.025 cm2)* showed no significant difference. Yet the RF as well as its fluctuation was significantly higher for valves with the closed geometry (RFC = 12.657 ± 7.669 %; RFSC = 8.72 ± 0.977 %)*. Recordings showed that the increased backflow was caused by pinwheeling due to a surplus of tissue material. Hydrodynamic testing of pediatric TVRs verified the semi-closed geometry being favourable. Despite the RF (RFC = 7.721 ± 0.348 cm2; RFSC = 5.172 ± 0.679 cm2), these valves also showed an improved opening behaviour ((TPGC = 20.929 ± 0.497 cm2; TPGSC = 15.972 ± 1.158 cm2); (EOAC = 0.629 ± 0.017 cm2; EOASC = 0.731 ± 0.026 cm2)). Both adult and pediatric TVR with semi-closed geometry show better fluiddynamic functionality compared to valves with a closed design due to less pinwheeling. Besides improved short-term functionality, less pinwheeling potentially prevents early valve degeneration and improves durability. *Results are representatively shown for a circular annulus geometry.

Valve-in-Valve-in-Valve

In the case of the degeneration of surgical aortic valve replacement (SAVR), the transcatheter aortic valve implantation (TAVI) has become the standard. However, these valves are also susceptible to deterioration. In such instances, a new TAVI implantation may be considered. We present the case of a patient with a SAVR who underwent two TAVI procedures, spaced 8 years apart. We discuss important practical aspects, including the risk of coronary obstruction and the final valve diameter.

Comparison of two self-expanding transcatheter heart valves for degenerated surgical bioprostheses: the AVENGER multicentre registry

BACKGROUND

There is a lack of comparative data on transcatheter aortic valve implantation (TAVI) in degenerated surgical prostheses (valve-in-valve [ViV]).

AIMS

We sought to compare outcomes of using two self-expanding transcatheter heart valve (THV) systems for ViV.

METHODS

In this retrospective multicentre registry, we included consecutive patients undergoing transfemoral ViV using either the ACURATE neo/neo2 (ACURATE group) or the Evolut R/PRO/PRO+ (EVOLUT group). The primary outcome measure was technical success according to Valve Academic Research Consortium (VARC)-3. Secondary outcomes were 30-day all-cause mortality, device success (VARC-3), coronary obstruction (CO) requiring intervention, rates of severe prosthesis-patient mismatch (PPM), and aortic regurgitation (AR) ≥moderate. Comparisons were made after 1:1 propensity score matching.

RESULTS

The study cohort comprised 835 patients from 20 centres (ACURATE n=251; EVOLUT n=584). In the matched cohort (n=468), technical success (ACURATE 92.7% vs EVOLUT 88.9%; p=0.20) and device success (69.7% vs 73.9%; p=0.36) as well as 30-day mortality (2.8% vs 1.6%; p=0.392) were similar between the two groups. The mean gradients and rates of severe PPM, AR ≥moderate, or CO did not differ between the groups. Technical and device success were higher for the ACURATE platform among patients with a true inner diameter (ID) >19 mm, whereas a true ID ≤19 mm was associated with higher device success - but not technical success - among Evolut recipients.

CONCLUSIONS

ViV TAVI using either ACURATE or Evolut THVs showed similar procedural outcomes. However, a true ID >19 mm was associated with higher device success among ACURATE recipients, whereas in patients with a true ID ≤19 mm, device success was higher when using Evolut.

Redo-TAVI with the ACURATE neo2 and Prime XL for balloon-expandable transcatheter heart valve failure

BACKGROUND

There are limited data regarding treatment for failed balloon-expandable transcatheter heart valves (THVs) in redo-transcatheter aortic valve implantation (TAVI).

AIMS

We aimed to assess THV performance, neoskirt height and expansion when performing redo-TAVI with the ACURATE platform inside a SAPIEN 3 (S3) compared to redo-TAVI with an S3 in an S3.

METHODS

Redo-TAVI was performed on the bench using each available size of the S3, the ACURATE neo2 (ACn2) and the next-generation ACURATE Prime XL (AC XL) implanted at 2 different depths within 20 mm/23 mm/26 mm/29 mm S3s serving as the "failed" index THV. Hydrodynamic testing was performed to assess THV function. Multimodality assessment was performed using photography, X-ray, microcomputed tomography (micro-CT), and high-speed videos.

RESULTS

The ACURATE in S3 combinations had favourable hydrodynamic performance compared to the S3 in S3 for all size combinations. In the 20 mm S3, redo-TAVI with the ACn2 had lower gradients compared to the S3 (mean gradient 16.3 mmHg for the ACn2 vs 24.7 mmHg for the 20 mm S3 in 20 mm S3). Pinwheeling was less marked for the ACURATE THVs than for the S3s. On micro-CT, the S3s used for redo-TAVI were underexpanded across all sizes. This was also observed for the ACURATE platform, but to a lesser extent.

CONCLUSIONS

Redo-TAVI with an ACn2/AC XL within an S3 has favourable hydrodynamic performance and less pinwheeling compared to an S3 in S3. This comes at the price of a taller neoskirt.

Deformation of transcatheter heart valves with mitral valve-in-valve

BACKGROUND

The use of oversizing in mitral valve-in-valve (MViV) procedures can lead to non-uniform expansion of transcatheter heart valves (THV). This may have implications for THV durability.

AIMS

The objective of this study was to assess the extent and predictors of THV deformation in MViV procedures.

METHODS

We examined 33 patients who underwent MViV with SAPIEN prostheses. The extent of THV deformation (deformation index, eccentricity, neosinus volume, asymmetric leaflet expansion and vertical deformation) and hypoattenuating leaflet thickening (HALT) were assessed using cardiac computed tomography (CT), performed prospectively at 30 days post-procedure. For descriptive purposes, the THV deformation index was calculated, with values >1.00 representing a more hourglass shape.

RESULTS

Non-uniform underexpansion of THV was common after MViV implantation, with a median expansion area of 74.0% (interquartile range 68.1-84.1) at the narrowest level and a THV deformation index of 1.21 (1.13-1.29), but circularity was maintained with eccentricity ranging from 0.24 to 0.28. The degree of oversizing was a key factor associated with greater underexpansion and a higher deformation index (β=-0.634; p<0.001; β=0.594; p<0.001, respectively). Overall, the incidence of HALT on the 30-day postprocedural CT was 27.3% (9 of 33). Most patients (32 of 33) were on anticoagulation therapy, but the prothrombin time and international normalised ratio (PT-INR) at the time of the CT scan was <2.5 in 23 of 32 patients. Among patients with a PT-INR of <2.5, HALT was predominantly observed with a high THV deformation index of ≥1.18.

CONCLUSIONS

THV deformation, i.e., underexpansion and an hourglass shape, commonly occurs after MViV implantation and is negatively affected by excessive oversizing. Optimising THV expansion during MViV could potentially prevent HALT.

Valve-in-Valve Transcatheter Mitral Valve Replacement: A Large First-in-Human 13-Year Experience

BACKGROUND

Favourable early outcomes have been reported following valve-in-valve transcatheter mitral valve replacement (TMVR). However, reports of long-term outcomes are lacking. We aimed to evaluate early and late outcomes in a large first-in-human valve-in-valve TMVR 13-year experience.

METHODS

All patients undergoing valve-in-valve TMVR in our centre from 2008 to 2021 were included. Clinical and echocardiographic outcomes, defined according to the Mitral Valve Academic Research Consortium, were reported.

RESULTS

A total of 119 patients were analysed: mean age 76.8 ± 10.2 years, mean Society of Thoracic Surgeons score 10.7 ± 6.8%, 55.4% female, 63.9% transapical access. Thirty-day mortality was 2.5% for the total population and 0.0% after transseptal TMVR. Maximum follow-up was 13.1 years. During a median follow-up of 3.4 years (interquartile range 1.8-5.3 years), 55 patients (46.2%) died, mainly from noncardiovascular causes. Valve hemodynamics were acceptable at 5 years, with 2.5% structural dysfunction. Patients treated from 2016 on (n = 68; 57.1%), following the advent of routine use of the Sapien 3 valve, CT screening, and transseptal access, were compared with those treated before 2016 (n = 51; 42.9%). Patients from 2016 on had a higher technical success rate (100.0% vs 94.1%; P = 0.04), shorter hospitalisation (P < 0.001), trending lower 30-day mortality (1.5% vs 3.9%; P = 0.4) and better 5-year survival (74.7% vs 41.1%; P = 0.03).

CONCLUSIONS

Valve-in-valve TMVR can be performed with little morbidity and low mortality. Mid- to long-term survival remains limited owing to advanced age and comorbidities. Structural bioprosthetic valve dysfunction was rare and redo TMVR feasible in selected patients. Outcomes continue to improve, but the role for valve-in-valve TMVR in lower surgical risk patients remains unclear.

Deformation of Transcatheter Heart Valve Following Valve-in-Valve Transcatheter Aortic Valve Replacement: Implications for Hemodynamics

BACKGROUND

Valve-in-valve (ViV) transcatheter aortic valve replacement (TAVR) may be associated with adverse hemodynamics, which might affect clinical outcomes.

OBJECTIVES

This study sought to evaluate the extent and predictors of transcatheter heart valve (THV) deformity in ViV TAVR and the relation to postprocedural hemodynamics.

METHODS

We examined 53 patients who underwent ViV TAVR in surgical heart valves with self-expanding Evolut prostheses. THV deformation was examined using cardiac computed tomography prospectively performed 30 days after ViV TAVR, and correlated with 30-day echocardiographic hemodynamic data.

RESULTS

Near complete expansion of the functional portion of the implanted ViV prostheses (ie, >90%) was observed in 16 (30.2%) patients. Factors related to greater expansion of the functional portion and consequently larger neosinus volume were absence of polymer surgical frame, higher implantation and use of balloon aortic valvuloplasty or bioprosthetic valve fracture during the procedure (all P < 0.05). Underexpansion of the functional portion, but not the valve inflow frame, was closely associated with mean gradient and effective orifice area at 30 days on echocardiography, with and without adjustment for the sizes of the THV and surgical heart valve.

CONCLUSIONS

Underexpansion of the functional portion of THV prostheses is common during ViV TAVR, occurs more frequently with deep implantation and the presence of a polymer surgical stent frame, and is associated with worse postprocedural hemodynamics. Procedural techniques, such as higher implantation and balloon postdilatation, may be used to help overcome problems with THV underexpansion and improve clinical outcomes.

Timing of bioprosthetic valve fracture in transcatheter valve-in-valve intervention: impact on valve durability and leaflet integrity

BACKGROUND

Bioprosthetic valve fracture (BVF) can be used to improve transcatheter heart valve (THV) haemodynamics following a valve-in-valve (ViV) intervention. However, whether BVF should be performed before or after THV deployment and the implications on durability are unknown.  Aims: We sought to assess the impact of BVF timing on long-term THV durability.

METHODS

The impact of BVF timing was assessed using small ACURATE neo (ACn) or 23 mm SAPIEN 3 (S3) THV deployed in 21 mm Mitroflow valves compared to no-BVF controls. Valves underwent accelerated wear testing up to 200 million (M) cycles (equivalent to 5 years). At 200M cycles, THV were evaluated by hydrodynamic testing, second-harmonic generation (SHG) microscopy, scanning electron microscopy (SEM) and histology.

RESULTS

At 200M cycles, the regurgitant fraction (RF) and effective orifice area (EOA) for the ACn were 8.03±0.30%/1.74±0.01 cm2 (no BVF), 12.48±0.70%/1.97±0.02 cm2 (BVF before ViV) and 9.29±0.38%/2.21±0.0 cm2 (BVF after ViV), respectively. For the S3 these values were 2.63±0.51%/1.26±0.01 cm2, 2.03±0.42%/1.65±0.01 cm2, and 1.62±0.38%/2.22±0.01 cm2, respectively. Further, SHG and SEM revealed a higher degree of superficial leaflet damage when BVF was performed after ViV for the ACn and S3. However, the histological analysis revealed significantly less damage, as determined by matrix density analysis, through the entire leaflet thickness when BVF was performed after ViV with the S3 and a similar but non-significant trend with the ACn.  Conclusions: BVF performed after ViV appears to offer superior long-term EOA without increased RF. Ultrastructure leaflet analysis reveals that the timing of BVF can differentially impact leaflets, with more superficial damage but greater preservation of overall leaflet structure when BVF is performed after ViV.

Prosthesis-patient mismatch after transcatheter aortic valve implantation

Prosthesis-patient mismatch (PPM), first described in 1978, occurs when a prosthetic valve functions normally, but has an effective orifice area that is too small relative to the patient's body surface area. It results in residual left ventricular afterload and higher transvalvular pressure gradient, which has been considered to impair prognosis. PPM following surgical aortic replacement is reportedly associated with worse clinical outcomes, such as high mortality. However, the impact of PPM on clinical outcomes after transcatheter aortic valve implantation (TAVI) remains unclear. There is conflicting evidence on the impact of PPM following TAVI due to differences across studies in terms of follow-up period, methods, patient populations, and type of bioprosthetic valve. The present review summarizes the most recent evidence on PPM after TAVI.

Impact of high-pressure balloon aortic valvuloplasty on the hydrodynamic result after a transcatheter valve-in-valve procedure

OBJECTIVES

The aim of this study was to investigate the degree of functional improvement of a transcatheter heart valve (THV) for valve-in-valve after bioprosthetic valve fracture (BVF) of three small surgical aortic valve bioprostheses (SAVBP) using high-pressure balloon aortic valvuloplasty (HP-BAV) under standardized ex-vivo-conditions.

METHODS

A THV 26 mm (Evolut R) and SAVBP 21 mm (Perimount Magna Ease, Trifecta, and Epic supra [n = 4] were used. Mean pressure gradient (MPG), effective orifice area (EOA), geometric orifice area (GOA), minimal internal diameter (MID), and pinwheeling index (PWI) were analyzed before and after HP-BAV of the SAVBP using a noncompliant balloon. Fracturing of the SAVBP was done before implantation of the THV and the balloon pressures at the point of fracture were recorded.

RESULTS

The Magna Ease and Epic fractured at balloon pressures of 18 and 8 atm, respectively. The Trifecta did not fracture up to a balloon pressure of 30 atm but was dilated. HP-BAV led to increased THV expansion as evident by straightened coaptation lines of the Evolut R 26 mm with reduced PWI, increased MID, and increased GOA in all 21 mm SAVBP. Evolut R showed significantly lower MPG and higher EOA as ViV in all prostheses after HP-BAV (p < 0.001). MPG and EOA of Evolut R differed regarding the SAVBP. Evolut R presented the lowest MPG and highest EOA in Magna Ease and the highest MPG and lowest EOA in Epic supra.

CONCLUSIONS

The degree of function improvement of the same THV as ViV after HP-BAV depends on the surgical valve model. Functional improvement can also be achieved without valve fracture.

TAVR for All? The Surgical Perspective

In spite of the noninferiority of transcatheter aortic valve replacement (TAVR) in high- and intermediate-risk patients, there are still obstacles that need to be overcome before the procedure is further expanded and clinically integrated. The lack of evidence on the long-term durability of the bioprostheses used for TAVR remains of particular concern. In addition, surgery may be preferred over TAVR in patients with bicuspid aortic valve (BAV) or with concomitant pathologies such as other valve diseases (mitral regurgitation/tricuspid regurgitation), aortopathy, and coronary artery disease. In this review, we discuss and summarize relevant data from clinical trials, current trends, and remaining obstacles, and provide our perspective on the indications for the expansion of TAVR.

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.

Bioprosthetic valve fracture: a practical guide

Valve-in-valve transcatheter aortic valve replacement (VIV TAVR) is currently indicated for the treatment of failed surgical tissue valves in patients determined to be at high surgical risk for re-operative surgical valve replacement. VIV TAVR, however, often results in suboptimal expansion of the transcatheter heart valve (THV) and can result in patient-prosthesis mismatch (PPM), particularly in small surgical valves. Bioprosthetic valve fracture (BVF) and bioprosthetic valve remodeling (BVR) can facilitate VIV TAVR by optimally expanding the THV and reducing the residual transvalvular gradient by utilizing a high-pressure inflation with a non-compliant balloon to either fracture or stretch the surgical valve ring, respectively. This article, along with the supplemental video, will provide patient selection, procedural planning and technical insights for performing BVF and BVR.

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.

Valve-in-Valve Transcatheter Aortic Valve Replacement, with Present-Day Innovations and Up-to-Date Techniques

Approximately 51,000 to 65,000 surgical aortic valve replacement (SAVR) cases are performed in the United States anually. Bioprosthetic degeneration commonly occurs within 10 to 15 years, and nearly 800 redo SAVR cases occur each year. Valve-in-valve transcatheter aortic valve replacement (ViV TAVR) has emerged as a safe and effective alternative, as the Food and Drug Administration approved ViV TAVR with self-expanding transcatheter heart valve in 2015 and balloon-expandable valve in 2017 for failed surgical valves cases at high risk of reoperation. We review ViV TAVR, with specific attention to procedural planning, technical challenges, associated complications, and long-term follow-up.

Valve Cracking Before Valve-In-Valve Transcatheter Aortic Valve Implantation to Treat Severe Paravalvular Leak

A patient with severe bioprosthesic patient-prosthesis mismatch, severe paravalvular leak, and symptoms of heart failure New York Heart Association functional class III was successfully treated using valve cracking followed by valve-in-valve transcatheter aortic valve implantation with excellent results at 1-year follow-up. (Level of Difficulty: Advanced.)

Long-Term Results (up to 20 Years) of 19 mm or Smaller Prostheses in the Aortic Position. Does Size Matter? A Propensity-Matched Survival Analysis

Background: The long-term performance of prostheses in the small aortic root is still unclear. Methods: Patients who received a 21 mm or smaller aortic valve between 2000–2018 were retrospectively analyzed. Propensity matching was used in order to account for baseline differences in 19 mm vs. 21 mm valve subgroups. Results: Survival at 10 years was 55.87 ± 5.54% for 19 mm valves vs. 57.17 ± 2.82% for 21 mm ones in the original cohort (p = 0.37), and 58.69 ± 5.61% in 19 mm valve recipients vs. 53.60 ± 5.66% for 21 mm valve subgroups in the matched cohort (p = 0.55). Smaller valves exhibited significantly more patient–prothesis mismatch (PPM) than larger ones (87.30% vs. 57.94%, p < 0.01). All-cause mortality was affected by PPM at 10 years (52.66 ± 3.28% vs. 64.38 ± 3.87%, p = 0.04) in the unmatched population. This difference disappeared, however, after matching: survival at 10 years was 51.82 ± 5.26% in patients with PPM and 63.12 ± 6.43% in patients without PPM. (p = 0.14) Conclusions: There is no survival penalty in using 19 mm prostheses in the small aortic root in the current era. Although PPM is more prevalent in smaller sized valve recipients, this does not translate into reduced survival at 10 years of follow-up.

Current Therapeutic Options in Aortic Stenosis

Aortic stenosis is the most common valvular disease requiring valve replacement. Valve replacement therapies have undergone progressive evolution since the 1960s. Over the last 20 years, transcatheter aortic valve replacement has radically transformed the care of aortic stenosis, such that it is now the treatment of choice for many, particularly elderly, patients. This review provides an overview of the pathophysiology, presentation, diagnosis, indications for intervention, and current therapeutic options for aortic stenosis.

Valve-in-valve transcatheter aortic valve implantation with fracturing of a failed small surgical aortic bioprosthesis: a case report

Background

Failure of a small surgical aortic bioprosthesis represents a challenging clinical scenario with valve-in-valve (ViV) transcatheter aortic valve implantation (TAVI) often resulting in patient-prosthesis mismatch. Bioprosthetic valve fracture (BVF) performed as a part of the ViV TAVI has recently emerged as an alternative approach with certain types of surgical bioprostheses.

Case summary

An 81-year-old woman with a history of three surgical aortic valve procedures presented with heart failure. Aortic bioprosthesis degeneration with severe stenosis and moderate regurgitation was found. The patient was deemed a high-risk surgical candidate and the heart team decided that ViV TAVI was the preferred treatment option. Due to the very small 19 mm stented surgical aortic bioprosthesis Mitroflow 19 mm (Sorin Group, Italy) we decided to perform BVF as a part of ViV TAVI to prevent patient-prosthesis mismatch. Since this was the first BVF procedure in our centre, an ex vivo BVF of the same kind of bioprosthetic valve was performed first. Subsequently, successful BVF with implantation of Evolut R 23 mm (Medtronic, USA) self-expandable transcatheter valve was performed. Excellent haemodynamic result was achieved and no periprocedural complications were present. The patient had an immediate major improvement in clinical status and remains asymptomatic after 6 months.

Discussion

Bioprosthetic valve fracture together with ViV TAVI is a safe and effective emerging technique for treatment of small surgical aortic bioprosthesis failure. Bioprosthetic valve fracture allows marked oversizing of implanted self-expandable transcatheter aortic valves, leading to excellent haemodynamic and clinical results. An ex vivo BVF can serve as an important preparatory step when introducing the new method.

Long term follow up of percutaneous treatment for degenerated Mitroflow prosthesis with self-expanding transcatheter aortic valve implantation

Background

The durability of aortic valve bioprosthesis and the structural valve deterioration (SVD) are could be treated with valve-in-valve (VIV) transcatheter aortic valve implantation (TAVI). This technique has been proven to be a feasible procedure with good results in selected patients. The aim of this work was to assess the long-term results of this TAVI with an autoexpandable valve in patients with failed Mitroflow (MF) bioprosthetic aortic valves.

Methods

Single center, observational and prospective study that included 65 consecutive patients with symptomatic failed MF bioprosthetic aortic valve, treated with VIV-TAVI. The primary endpoints were clinical long-term events including all-cause mortality, cardiovascular mortality, re-hospitalization due to heart failure, stroke/transient ischemic attack (TIA) and endocarditis. Secondary endpoints were the absence of SVD or patient-prosthesis mismatch (PPM) and valve hemodynamics analysis at follow-up.

Results

Between March 2012 to July 2019, 65 symptomatic patients (age 80.4±5.9 years) with degenerated MF valves (numbers 19: 27.7%; 21: 38.5%; 23: 21.5%; 25: 12.3%) underwent CoreValve (n=11) or Evolut R (n=54) implantation (23, 26 and 29 mm sizes). The STS predicted risk of mortality was 6.39%±5.62%. The primary combined endpoint occurred in 32.3% of the cases. A total of 13 patients (20%) died during follow-up, but 4 (7.3%) from cardiovascular causes. Two patients were reported of having a stroke/TIA and 5 readmissions for cardiovascular causes were reported (2 of them within the first 30 days). Twenty-five patients (38.5%) presented PPM during follow-up, being PPM severe in 15 (23.1%).

Conclusions

Self-expanding TAVI for degenerated MF bioprosthesis has favourable long-term outcomes. It is a good option in order to avoid the risks of redo surgery in selected patients.

Implications of hydrodynamic testing to guide sizing of self-expanding transcatheter heart valves for valve-in-valve procedures

AIMS

The commonly used valve-in-valve (VIV) app recommends sizing based on dimensions of both the transcatheter heart valve (THV) and bioprosthetic surgical valve. The implications of hydrodynamic testing to guide VIV sizing are poorly understood. This bench study assessed the hydrodynamic performance of different sizes of self-expanding supra-annular THVs in three different surgical aortic bioprostheses at different implantation depths.

METHODS

A small versus medium ACURATE neo (ACn), and a 26 mm versus 29 mm Evolut R were assessed after VIV implantation in 25 mm Mitroflow, Mosaic, and Magna Ease aortic surgical bioprostheses, at three implantation depths (+2 mm, -2 mm, and -6 mm).

RESULTS

The medium-sized ACn had lower gradients compared to the small ACn when the THV was implanted high (+2 mm, or -2 mm). The 29 mm Evolut R had lower gradients compared to a 26 mm Evolut R for all implantation depths, except for a depth of -2 mm in the 25 mm Mitroflow. The medium ACn and 29 mm Evolut R had larger effective orifice areas compared to the small ACn and 26 mm Evolut R, respectively. Both Evolut R sizes had acceptable regurgitant fractions (<15%), while both ACn sizes were above the acceptable performance criteria (>15%), at all implantation depths.

CONCLUSIONS

Use of a larger self-expanding THV was associated with superior hydrodynamic performance if the THV was implanted high. Hydrodynamic testing can provide additional information to the VIV app to help guide VIV sizing.

Bioprosthetic Aortic Valve Fracture During Valve-in-valve Transcatheter Aortic Valve Implantation

The limited durability of surgical bioprostheses, combined with an ageing population, has led to an increasing demand for replacing degenerated bioprosthetic surgical heart valves, which is projected to increase. Valve-in-valve transcatheter aortic valve implantation involves implanting a transcatheter heart valve within a degenerated bioprosthetic surgical heart valve. A significant minority of patients, however, are left with a suboptimal haemodynamic result with high residual gradients. This is more common with smaller surgical bioprostheses, and may be associated with a worse prognosis. The novel concept of fracturing the previously implanted bioprosthetic surgical heart valve during valve-in-valve transcatheter aortic valve implantation to create a more favourable haemodynamic profile has shown great promise, particularly in smaller valves. Herein, we describe the benefits, limitations and potential complications of this novel approach.