Aortic Bioprosthetic Valve Durability

Biological tissue for transcatheter aortic valve: The effect of crimping on fatigue strength

Transcatheter aortic valve replacement (TAVR) has become today the most attractive procedure to relieve patients from aortic valve disease. However, the procedure requires crimping biological tissue within a metallic stent for low diameter catheter insertion purpose. This step induces specific stress in the leaflets especially when the crimping diameter is small. One concern about crimping is the potential degradations undergone by the biological tissue, which may limit the durability of the valve once implanted. The purpose of the present work is to investigate the mechanical damage undergone by bovine pericardium tissue during compression and analyze how this degradation evolves with time under fatigue testing conditions. Pericardium 500 μm thick pericardium ribbons (5 mm large, 70 mm long) were crimped down to 12 Fr for 30 and 50 min within a metallic stent to replicate the heart valve crimping configuration. After crimping, samples underwent cyclic fatigue flexure and pressure loading over 0.5 Mio cycles. Samples were characterized for mechanical performances before crimping, after crimping and after fatigue testing in order to assess potential changes in the mechanical properties of the tissue after each step. Results bring out that the ultimate tensile strength is not modified through the process. However an increase in the modulus shows that the crimping step tends to stiffen the pericardium. This may have an influence on the lifetime of the implant.

Transcatheter Aortic Valve Replacement in Low Surgical Risk Patients: An Updated Metanalysis of Extended Follow-Up Randomized Controlled Trials

The long-term safety and effectiveness of transcatheter aortic valve replacement (TAVR) compared with surgical aortic valve replacement (SAVR) in low surgical risk has not been evaluated in a pooled analysis. An electronic database search was conducted for randomized controlled trials with a maximal 5 years clinical and echocardiographic follow-up including low surgical risk patients who underwent TAVR or SAVR. We calculated odds ratio (OR) and 95% confidence intervals (CIs) using a random-effects model. Subgroups analysis was performed for permanent pacemaker implantation and paravalvular leaks. Three randomized controlled trials were included with a total of 2,611 low surgical risk patients (Society of Thoracic Surgeons score <4%). Compared with SAVR, the TAVR group had similar rates of all-cause mortality (OR 0.94,95% CI 0.65 to 1.37, p = 0.75) and disabling stroke (OR 0.84, 95% CI 0.52 to 1.36, p = 0.48). No significant differences were registered in the TAVR group in terms of major cardiovascular events (OR 0.96, 95% CI 0.67 to 1.38, p = 0.83), myocardial infarction (OR 0.69, 95% CI 0.34 to 1.40, p = 0.31), valve thrombosis (OR 3.11, 95% CI 0.29 to 33.47, p = 0.35), endocarditis (OR 0.71,95% CI 0.35 to 1.48, p = 0.36), aortic valve reintervention (OR 0.93, 95% CI 0.52 to 1.66, p = 0.80), and rehospitalization (OR 0.80, 95% CI 0.52 to 1.02, p = 0.07) compared with SAVR. However, TAVR patients had a higher risk of paravalvular leaks (OR 8.21, 95% CI 4.18 to 16.14, p <0.00001), but lower rates of new-onset atrial fibrillation (OR 0.27,95% CI 0.17 to 0.30, p <0.0001). The rates of permanent pacemaker implantation were comparable from 1 year up to a maximum of 5 years (OR 1.32, 95% CI 0.88 to 1.97, p = 0.18). Lastly, TAVR had a greater effective orifice area (0.10 cm2/m2, 95% CI 0.05 to 0.15, p = 0.0001), but similar transvalvular mean gradients (0.60, 95% CI 3.94 to 2.73, p = 0.72). In conclusion, TAVR patients had similar long-term outcomes compared with SAVR, except for an elevated risk of paravalvular leaks in the TAVR group and increased rates of atrial fibrillation in the SAVR cohort.

A personalized aortic valve replacement using computed tomography-guided aortic valve neocuspidization. Analysis of mid-term results compared to standard Ozaki technique

BACKGROUND

The original Ozaki technique involves sizing the neovalve cusps during cross-clamp. It leads to prolonging the ischemic time compared to standard surgical AVR. Measurements taken on the collapsed Aortic Root (AR) may also be inaccurate. We use preoperative Computed Tomography (CT) to perform more accurate sizing in physiological conditions and shorten the ischemic time. This study analyzes the results of the CT-guided Aortic Valve Neocuspidization (AVNeo) compared with the Ozaki technique.

METHODS

The validity of the concept was evaluated ex vivo. Experimental valves underwent geometric, CT, and hydrodynamic controls. In the clinical phase of the study, we prospectively analyzed patients who received CT-guided AVNeo (N ​= ​7, Group 1). The control group enrolled patients who were operated on after the standard AVNeo technique (N ​= ​15, Group 2).

RESULTS

In Group 1, Aortic Cross-Clamp (70.3 ​± ​17.0 vs. 91 ​± ​21.3 ​min, ρ ​= ​0.026) and Bypass times (92.9 ​± ​21.0 vs. 123 ​± ​24.8 ​min, ρ ​= ​0.011) were significantly shorter. At discharge, the peak (11.7 ​± ​2.75 vs. 15.4 ​± ​4.66 ​mm Hg, ρ ​= ​0.032) and mean Aortic Valve (AV) gradient (6.29 ​± ​1.25 vs. 7.87 ​± ​2.33 ​mm Hg, ρ ​= ​0.052) were lower in Group 1. Only one patient in Group 2 had Aortic Insufficiency (AI) greater than mild. The mean follow-up was 49.6 ​± ​6.9 months in both groups. There were no late deaths or any valve-related events detected in any patient. EchoCG revealed that peak (10.0 ​± ​2.65 vs. 12.6 ​± ​4.05 ​mm Hg, ρ ​= ​0.090) and mean AV gradient (5.14 ​± ​1.35 vs. 6.73 ​± ​2.25 ​mm Hg, ρ ​= ​0.054) also were lower in Group 1. AI indexes were stable in both Groups.

CONCLUSIONS

CT-guided AVNeo is an example of personalized medicine in the surgical treatment of heart valve pathology. It allows the development of a biological AV that adapts to the patient's anatomy, shortens ischemic time, and results in better hemodynamics. A more significant number of clinical observations and longer follow-up are warranted to prove the viability of the concept.

Biomechanical Scaffolds of Decellularized Heart Valves Modified by Electrospun Polylactic Acid

Enhancing the mechanical properties and cytocompatibility of decellularized heart valves is the key to promote the application of biological heart valves. In order to further improve the mechanical properties, the electrospinning and non-woven processing methods are combined to prepare the polylactic acid (PLA)/decellularized heart valve nanofiber-reinforced sandwich structure electrospun scaffold. The effect of electrospinning time on the performance of decellularized heart valve is investigated from the aspects of morphology, mechanical properties, softness, and biocompatibility of decellularized heart valve. Results of the mechanical tests show that compared with the pure decellularized heart valve, the mechanical properties of the composite heart valve were significantly improved with the tensile strength increasing by 108% and tensile strain increased by 571% when the electrospinning time exceeded 2 h. In addition, with this electrospinning time, the composite heart valve has a certain promoting effect on the human umbilical vein endothelial cells proliferation behavior. This work provides a promising foundation for tissue heart valve reendothelialization to lay the groundwork for organoid.

Impact of Elevated Gradients After Transcatheter Aortic Valve Implantation for Degenerated Surgical Aortic Valve Bioprostheses

BACKGROUND

Elevated aortic valve gradients are common after transcatheter aortic valve implantation for degenerated surgical aortic valve replacement bioprostheses, but their clinical impact is uncertain.

METHODS

A total of 12 122 patients who underwent transcatheter aortic valve implantation-in-surgical aortic valve replacement from November 2011 to December 2019 in the Society of Thoracic Surgery/American College of Cardiology Transvalvular Therapeutics Registry were included. The primary outcome was a composite of 1-year all-cause mortality, stroke, myocardial infarction, or valve reintervention. Secondary outcomes included 1-year all-cause mortality, readmission, and change from baseline 12-question self-administered Kansas City Cardiomyopathy Questionnaire-Overall Summary Score. Due to nonlinearity observed with restricted cubic splines analysis, a Cox regression analysis with aortic valve mean gradient modeled as a spline-continuous variable (with 20 mm Hg as a cutoff) was used to study the 1-year composite outcome and mortality.

RESULTS

The composite outcome occurred most frequently in patients with aortic valve mean gradient ≥30 and <10 mm Hg, as compared with those with 10 to 20 and 20 to 30 mm Hg ranges (unadjusted rates, 13.9%, 12.1%, 7.5%, and 6.5%, respectively; P=0.002). When the mean aortic valve gradient was ≥20 mm Hg, higher gradients were associated with greater risk of the 1-year composite outcome (adjusted hazard ratio, 1.02 [1.02-1.03] per mm Hg; P<0.001) and 1-year mortality (adjusted hazard ratio, 1.02 [1.00-1.03] per mm Hg; P=0.007). Whereas when the mean aortic valve gradient was <20 mm Hg, higher gradients were not significantly associated with the composite outcome (adjusted hazard ratio, 0.99 [0.98-1.003] per mm Hg; P=0.12) but were associated with lower 1-year mortality (adjusted hazard ratio, 0.98 [0.97-0.99] per mm Hg; P=0.007).

CONCLUSIONS

The relationship between postprocedural aortic valve mean gradient after transcatheter aortic valve implantation-in-surgical aortic valve replacement and clinical outcomes is complex and nonlinear, with relatively greater adverse events occurring at low and high gradient extremes. Further study of factors mediating the relationship between postprocedural gradients and clinical outcomes, including low-flow states, is necessary.

A multimodal approach to predict prosthesis-patient mismatch in patients undergoing valve-in-valve trans-catheter aortic valve implantation

AIMS

The valve-in-valve transcatheter-aortic-valve-implantation (VIV-TAVI) represents an emerging procedure for the treatment of degenerated aortic bio-prostheses, and the occurrence of patient-prosthesis mismatch (PPM) after VIV-TAVI might affect its clinical efficacy. This study aimed to test a multimodal imaging approach to predict PPM risk during the TAVI planning phase and assess its clinical predictivity in VIV-TAVI procedures.

METHODS

Consecutive patients undergoing VIV-TAVI procedures at our Institution over 6 years were screened and those treated by self-expandable supra-annular valves were selected. The effective orifice area (EOA) was calculated with a hybrid Gorlin equation combining echocardiographic data with invasive hemodynamic assessment. Severe PPM was defined according to such original multimodality assessment as EOAi≤0.65 cm2/m2 (if BMI < 30 kg/m2) or < 0.55 cm2/m2 (if BMI ≥ 30 kg/m2). The primary endpoint was a composite of all-cause mortality and valve-related re-hospitalization during the clinical follow-up.

RESULTS

A total of 40 VIV-TAVI was included in the analysis. According to the pre-specified multimodal imaging modality assessment, 18 patients (45.0 %) had severe PPM. Among all baseline clinical and anatomical characteristics, estimated glomerular filtration rate before VIV-TAVI (OR 0.872, 95%CI[0.765-0.994],p = 0.040), the echocardiographic pre-procedural ≥moderate AR (OR 0.023, 95%CI[0.001-0.964],p = 0.048), the MSCT-derived effective internal area (OR 0.958, 95%CI[0.919-0.999],p = 0.046) and the implantation depth (OR 2.050, 95%CI[1.028-4.086],p = 0.041) resulted as independent predictors of severe PPM at multivariable logistic analysis. At a mean follow-up of 630 days, patients with severe PPM showed a higher incidence of the primary endpoint (9.1%vs.44.4 %;p = 0.023).

CONCLUSION

In VIV-TAVI using self-expandable supra-annular valves, a multimodal imaging approach might improve clinical outcome predicting severe PPM occurrence.

Self-Expanding or Balloon-Expandable TAVR in Patients with a Small Aortic Annulus

BACKGROUND

Patients with severe aortic stenosis and a small aortic annulus are at risk for impaired valvular hemodynamic performance and associated adverse cardiovascular clinical outcomes after transcatheter aortic-valve replacement (TAVR).

METHODS

We randomly assigned patients with symptomatic severe aortic stenosis and an aortic-valve annulus area of 430 mm2 or less in a 1:1 ratio to undergo TAVR with either a self-expanding supraannular valve or a balloon-expandable valve. The coprimary end points, each assessed through 12 months, were a composite of death, disabling stroke, or rehospitalization for heart failure (tested for noninferiority) and a composite end point measuring bioprosthetic-valve dysfunction (tested for superiority).

RESULTS

A total of 716 patients were treated at 83 sites in 13 countries (mean age, 80 years; 87% women; mean Society of Thoracic Surgeons Predicted Risk of Mortality, 3.3%). The Kaplan-Meier estimate of the percentage of patients who died, had a disabling stroke, or were rehospitalized for heart failure through 12 months was 9.4% with the self-expanding valve and 10.6% with the balloon-expandable valve (difference, -1.2 percentage points; 90% confidence interval [CI], -4.9 to 2.5; P<0.001 for noninferiority). The Kaplan-Meier estimate of the percentage of patients with bioprosthetic-valve dysfunction through 12 months was 9.4% with the self-expanding valve and 41.6% with the balloon-expandable valve (difference, -32.2 percentage points; 95% CI, -38.7 to -25.6; P<0.001 for superiority). The aortic-valve mean gradient at 12 months was 7.7 mm Hg with the self-expanding valve and 15.7 mm Hg with the balloon-expandable valve, and the corresponding values for additional secondary end points through 12 months were as follows: mean effective orifice area, 1.99 cm2 and 1.50 cm2; percentage of patients with hemodynamic structural valve dysfunction, 3.5% and 32.8%; and percentage of women with bioprosthetic-valve dysfunction, 10.2% and 43.3% (all P<0.001). Moderate or severe prosthesis-patient mismatch at 30 days was found in 11.2% of the patients in the self-expanding valve group and 35.3% of those in the balloon-expandable valve group (P<0.001). Major safety end points appeared to be similar in the two groups.

CONCLUSIONS

Among patients with severe aortic stenosis and a small aortic annulus who underwent TAVR, a self-expanding supraannular valve was noninferior to a balloon-expandable valve with respect to clinical outcomes and was superior with respect to bioprosthetic-valve dysfunction through 12 months. (Funded by Medtronic; SMART ClinicalTrials.gov number, NCT04722250.).

Recent Advances in the Modification and Improvement of Bioprosthetic Heart Valves

Valvular heart disease (VHD) has become a burden and a growing public health problem in humans, causing significant morbidity and mortality worldwide. An increasing number of patients with severe VHD need to undergo heart valve replacement surgery, and artificial heart valves are in high demand. However, allogeneic valves from donors are lacking and cannot meet clinical practice needs. A mechanical heart valve can activate the coagulation pathway after contact with blood after implantation in the cardiovascular system, leading to thrombosis. Therefore, bioprosthetic heart valves (BHVs) are still a promising way to solve this problem. However, there are still challenges in the use of BHVs. For example, their longevity is still unsatisfactory due to the defects, such as thrombosis, structural valve degeneration, calcification, insufficient re-endothelialization, and the inflammatory response. Therefore, strategies and methods are needed to effectively improve the biocompatibility and longevity of BHVs. This review describes the recent research advances in BHVs and strategies to improve their biocompatibility and longevity.

Transcatheter valve-in-valve interventions after aortic root replacement: A systematic review

Structural valve deterioration after aortic root replacement (ARR) surgery may be treated by transcatheter valve-in-valve (ViV-TAVI) intervention. However, several technical challenges and outcomes are not well described. The aim of the present review was to analyze the outcomes of ViV-TAVI in deteriorated ARR. This review included studies reporting any form of transcatheter valvular intervention in patients with a previous ARR. All forms of ARR were considered, as long as the entire root was replaced. Pubmed, ScienceDirect, SciELO, DOAJ, and Cochrane library databases were searched until September 2023. Overall, 86 patients were included from 31 articles that met our inclusion criteria out of 741 potentially eligible studies. In the entire population, the mean time from ARR to reintervention was 11.0 years (range: 0.33-22). The most frequently performed techniques/grafts for ARR was homograft (67.4%) and the main indication for intervention was aortic regurgitation (69.7%). Twenty-three articles reported no postoperative complications. Six (7.0%) patients required permanent pacemaker implantation (PPI) after the ViV-TAVI procedure, and 4 (4.7%) patients had a second ViV-TAVI implant. There were three device migrations (3.5%) and 1 stroke (1.2%). Patients with previous ARR present a high surgical risk. ViV-TAVI can be considered in selected patients, despite unique technical challenges that need to be carefully addressed according to the characteristics of the previous surgery and on computed tomography analysis.

Transcatheter or surgical aortic valve implantation: 10-year outcomes of the NOTION trial

BACKGROUND AND AIMS

Transcatheter aortic valve implantation (TAVI) has become a viable treatment option for patients with severe aortic valve stenosis across a broad range of surgical risk. The Nordic Aortic Valve Intervention (NOTION) trial was the first to randomize patients at lower surgical risk to TAVI or surgical aortic valve replacement (SAVR). The aim of the present study was to report clinical and bioprosthesis outcomes after 10 years.

METHODS

The NOTION trial randomized 280 patients to TAVI with the self-expanding CoreValve (Medtronic Inc.) bioprosthesis (n = 145) or SAVR with a bioprosthesis (n = 135). The primary composite outcome was the risk of all-cause mortality, stroke, or myocardial infarction. Bioprosthetic valve dysfunction (BVD) was classified as structural valve deterioration (SVD), non-structural valve dysfunction (NSVD), clinical valve thrombosis, or endocarditis according to Valve Academic Research Consortium-3 criteria. Severe SVD was defined as (i) a transprosthetic gradient of 30 mmHg or more and an increase in transprosthetic gradient of 20 mmHg or more or (ii) severe new intraprosthetic regurgitation. Bioprosthetic valve failure (BVF) was defined as the composite rate of death from a valve-related cause or an unexplained death following the diagnosis of BVD, aortic valve re-intervention, or severe SVD.

RESULTS

Baseline characteristics were similar between TAVI and SAVR: age 79.2 ± 4.9 years and 79.0 ± 4.7 years (P = .7), male 52.6% and 53.8% (P = .8), and Society of Thoracic Surgeons score < 4% of 83.4% and 80.0% (P = .5), respectively. After 10 years, the risk of the composite outcome all-cause mortality, stroke, or myocardial infarction was 65.5% after TAVI and 65.5% after SAVR [hazard ratio (HR) 1.0; 95% confidence interval (CI) 0.7-1.3; P = .9], with no difference for each individual outcome. Severe SVD had occurred in 1.5% and 10.0% (HR 0.2; 95% CI 0.04-0.7; P = .02) after TAVI and SAVR, respectively. The cumulative incidence for severe NSVD was 20.5% and 43.0% (P < .001) and for endocarditis 7.2% and 7.4% (P = 1.0) after TAVI and SAVR, respectively. No patients had clinical valve thrombosis. Bioprosthetic valve failure occurred in 9.7% of TAVI and 13.8% of SAVR patients (HR 0.7; 95% CI 0.4-1.5; P = .4).

CONCLUSIONS

In patients with severe AS and lower surgical risk randomized to TAVI or SAVR, the risk of major clinical outcomes was not different 10 years after treatment. The risk of severe bioprosthesis SVD was lower after TAVR compared with SAVR, while the risk of BVF was similar.

Role of lipoprotein(a) concentrations in bioprosthetic aortic valve degeneration

OBJECTIVES

Lipoprotein(a) (Lp(a)) is associated with an increased incidence of native aortic stenosis, which shares similar pathological mechanisms with bioprosthetic aortic valve (bAV) degeneration. However, evidence regarding the role of Lp(a) concentrations in bAV degeneration is lacking. This study aims to evaluate the association between Lp(a) concentrations and bAV degeneration.

METHODS

In this retrospective multicentre study, patients who underwent a bAV replacement between 1 January 2010 and 31 December 2020 and had a Lp(a) measurement were included. Echocardiography follow-up was performed to determine the presence of bioprosthetic valve degeneration, which was defined as an increase >10 mm Hg in mean gradient from baseline with concomitant decrease in effective orifice area and Doppler Velocity Index, or new moderate/severe prosthetic regurgitation. Levels of Lp(a) were compared between patients with and without degeneration and Cox regression analysis was performed to investigate the association between Lp(a) levels and bioprosthetic valve degeneration.

RESULTS

In total, 210 cases were included (mean age 74.1±9.4 years, 72.4% males). Median time between baseline and follow-up echocardiography was 4.4 (IQR 3.7) years. Bioprostheses degeneration was observed in 33 (15.7%) patients at follow-up. Median serum levels of Lp(a) were significantly higher in patients affected by degeneration versus non-affected cases: 50.0 (IQR 72.0) vs 15.6 (IQR 48.6) mg/dL, p=0.002. In the regression analysis, high Lp(a) levels (≥30 mg/dL) were associated with degeneration both in a univariable analysis (HR 3.6, 95% CI 1.7 to 7.6, p=0.001) and multivariable analysis adjusted by other risk factors for bioprostheses degeneration (HR 4.4, 95% CI 1.9 to 10.4, p=0.001).

CONCLUSIONS

High serum Lp(a) is associated with bAV degeneration. Prospective studies are needed to confirm these findings and to investigate whether lowering Lp(a) levels could slow bioprostheses degradation.

Transcatheter aortic valve durability, predictors of bioprosthetic valve dysfunction, longer-term outcomes - a review

INTRODUCTION

Transcatheter aortic valve implantation (TAVI) is one of the most significant inventions in cardiology, as it provides a viable minimally invasive treatment option for patients with aortic stenosis, the most common valvular disease in the developed world and one with a poor prognosis when left untreated. Using data available to date, this review aims to discuss and identify possible predictors of TAVI valve durability - an essential requirement for the device's wide-spread use, especially in younger patients.

AREAS COVERED

This article explores the main causes of bioprosthetic valve dysfunction (BVD) based on pathophysiology and available data, and reviews possible predictors of BVD including prosthesis-related, procedure-related, and patient-related factors. An emphasis is made on affectable predictors, which could potentially be targeted with prevention management and improve valve durability. A literature search of online medical databases was conducted using relevant key words and dates; significant clinical trials were identified. A brief overview of important randomized controlled trials with mid to long-term follow-up is included in this article.

EXPERT OPINION

Identifying modifiable predictors of valve dysfunction presents an opportunity to enhance and predict valve durability - a necessity as patients with longer life-expectancies are being considered for the procedure.

Metformin ameliorates valve interstitial cell calcification by promoting autophagic flux

Calcific aortic valve disease (CAVD) is the most common heart disease of the developed world. It has previously been established that metformin administration reduces arterial calcification via autophagy; however, whether metformin directly regulates CAVD has yet to be elucidated. In the present study we investigated whether metformin alleviates valvular calcification through the autophagy-mediated recycling of Runx2. Calcification was reduced in rat valve interstitial cells (RVICs) by metformin treatment (0.5-1.5 mM) (P < 0.01), with a marked decrease in Runx2 protein expression compared to control cells (P < 0.05). Additionally, upregulated expression of Atg3 and Atg7 (key proteins required for autophagosome formation), was observed following metformin treatment (1 mM). Blocking autophagic flux using Bafilomycin-A1 revealed colocalisation of Runx2 with LC3 puncta in metformin treated RVICs (P < 0.001). Comparable Runx2 accumulation was seen in LC3 positive autolysosomes present within cells that had been treated with both metformin and hydroxychloroquine in combination (P < 0.001). Mechanistic studies employing three-way co-immunoprecipitation with Runx2, p62 and LC3 suggested that Runx2 binds to LC3-II upon metformin treatment in VICs. Together these studies suggest that the utilisation of metformin may represent a novel strategy for the treatment of CAVD.

Open transcatheter double valve-in-valve replacement for degenerated bioprostheses on the arrested heart

Background

Failing bioprosthesis is an emerging issue due to (i) a shift towards liberal bioprosthesis implantation instead of mechanical prosthesis and (ii) an ageing population. Management of high-risk patients with bioprosthesis degeneration remains challenging.

Case summary

An 82-year-old patient with history of aortic and mitral valve replacement six years before presents with severe dyspnoea. Echocardiograpic assessment reveals (i) structural valve degeneration of the mitral prosthesis (severe stenosis and regurgitation) with concomitant major annular calcifications and (ii) structural valve degeneration of the aortic prosthesis with low-flow, low-gradient restenosis. Due to mitral annular calcifications, the risk of double valve re-replacement and the age of the patient conventional reoperation was deemed very high. The patient is evaluated for transapical double valve implantation. This option is rejected due to the high risk of left ventricular outflow obstruction. The patient is treated with an open transcatheter double valve-in-valve procedure at the following sequence: leaflet resection of the mitral bioprosthesis, mitral valve implantation and fixation under direct view, leaflet resection of the aortic bioprosthesis, and valve frame cracking and aortic valve implantation under direct view. Post-bypass echocardiography shows neither left ventricular outflow tract obstruction nor paravalvular leak or prosthesis dysfunction. The patient is extubated on the first post-operative day and transferred to normal care unit.

Discussion

Open transcatheter double valve-in-valve replacement for degenerated bioprostheses on the arrested heart might be a valuable alternative to treat selected high-risk patients with bioprosthetic valve degeneration.

Association between remnant cholesterol and progression of bioprosthetic valve degeneration

AIMS

Remnant cholesterol (RC) seems associated with native aortic stenosis. Bioprosthetic valve degeneration may share similar lipid-mediated pathways with aortic stenosis. We aimed to investigate the association of RC with the progression of bioprosthetic aortic valve degeneration and ensuing clinical outcomes.

METHODS AND RESULTS

We enrolled 203 patients with a median of 7.0 years (interquartile range: 5.1-9.2) after surgical aortic valve replacement. RC concentration was dichotomized by the top RC tertile (23.7 mg/dL). At 3-year follow-up, 121 patients underwent follow-up visit for the assessment of annualized change in aortic valve calcium density (AVCd). RC levels showed a curvilinear relationship with an annualized progression rate of AVCd, with increased progression rates when RC >23.7 mg/dL (P = 0.008). There were 99 deaths and 46 aortic valve re-interventions in 133 patients during a median clinical follow-up of 8.8 (8.7-9.6) years. RC >23.7 mg/dL was independently associated with mortality or re-intervention (hazard ratio: 1.98; 95% confidence interval: 1.31-2.99; P = 0.001).

CONCLUSION

Elevated RC is independently associated with faster progression of bioprosthetic valve degeneration and increased risk of all-cause mortality or aortic valve re-intervention.

Self-Expanding Transcatheter Aortic Valves Optimize Transvalvular Hemodynamics Independent of Intra- Versus Supra-Annular Design

This study sought to characterize transvalvular hemodynamics during the first 30 days after transcatheter aortic valve implantation (TAVI) across various transcatheter heart valves (THVs), while adjusting for annular dimensions. This was an observational study of TAVIs from September 2021 to October 2022. The primary outcome was mean transvalvular pressure gradient (TVPG), measured using transthoracic echocardiography at day 0, day 1, and day 30 post-TAVI, and were compared across 3 THV, including the self-expandable intra-annular Portico (Abbott Vascular, Santa Clara, California) valve, the balloon-expandable SAPIEN 3 Ultra (Edwards Lifesciences, Irvine, California), and the self-expandable supra-annular Evolut Pro+ (Medtronic, Minneapolis, Minnesota). A total of 560 patients who underwent TAVI were identified, of which 106 (18.9%) received a Portico THV, 176 (31.4%) received a SAPIEN THV, and 278 (49.6%) received an Evolut THV. For Portico THV, the TVPG on day 0 increased from 6.0 (4.7 to 9.0) to 7.0 (6.0 to 10.0) by day 30 (p = 0.009). For SAPIEN THV, the TVPG on day 0 increased from 6.5 (5.0 to 8.0) to 12.0 (9.0 to 15.0) by day 30 (p <0.001). For Evolut THV, the TVPG on day 0 increased from 6.0 (5.0 to 9.0) to 7.2 (5.0 to 10.0) by day 30 (p = 0.001). Adjusting for time and annular diameter in a multivariable mixed effects model, the SAPIEN group had a significantly greater increase in TVPG over time than the Evolut reference group (p <0.001), while there was no difference in the change of TVPG over time for the Portico group vs. the Evolut group (p = 0.874). In conclusion, compared with balloon-expandable valves, self-expanding THV may optimize transvalvular hemodynamics across all annular diameters, independent of their supra-annular and intra-annular design.

Bioprosthetic Valves for Lifetime Management of Aortic Stenosis: Pearls and Pitfalls

This review explores the use of bioprosthetic valves for the lifetime management of patients with aortic stenosis, considering recent advancements in surgical (SAV) and transcatheter bioprostheses (TAV). We examine the strengths and challenges of each approach and their long-term implications. We highlight differences among surgical bioprostheses regarding durability and consider novel surgical valves such as the Inspiris Resilia, Intuity rapid deployment, and Perceval sutureless bioprostheses. The impact of hemodynamics on the performance and durability of these prostheses is discussed, as well as the benefits and considerations of aortic root enlargement during Surgical Aortic Valve Replacement (SAVR). Alternative surgical methods like the Ross procedure and the Ozaki technique are also considered. Addressing bioprosthesis failure, we compare TAV-in-SAV with redo SAVR. Challenges with TAVR, such as TAV explantation and considerations for coronary circulation, are outlined. Finally, we explore the potential challenges and limitations of several clinical strategies, including the TAVR-first approach, in the context of aortic stenosis lifetime management. This concise review provides a snapshot of the current landscape in aortic bioprostheses for physicians and surgeons.

Right ventricular outflow tract obstruction associated with neointimal tissue accumulation and distortion of the Harmony TPV25 stent frame: Potential mechanisms and treatment

BACKGROUND

The Harmony TPV25 transcatheter pulmonary valve (Medtronic Inc.) is constructed with a self-expanding stent frame comprising six zigged nitinol wires sewn together and covered with knitted polyester fabric, with flared inflow and outflow ends and a porcine pericardial valve sutured to the central portion of the device. It was approved for treatment of pulmonary regurgitation after prior right ventricular outflow tract repair in 2021. Early outcomes of this procedure have been excellent, but little is known about valve durability or ultimate mechanisms of dysfunction.

METHODS

We collected data on patients who underwent reintervention for TPV25 dysfunction and described findings related to distortion of the stent frame and tissue accumulation.

RESULTS

We describe six patients who underwent valve-in-valve implant for TPV25 obstruction (peak catheterization gradient peak 28-73 mmHg) 10-28 months after implant. In all cases, there was tissue accumulation within the inflow and valve-housing segments of the device and deformation of the self-expanding valve frame characterized by variable circumferential narrowing at the junction between the valve housing and the inflow and outflow portions of the device, with additional geometric changes in all segments. All six patients underwent valve-in-valve implant that results in a final peak gradient ≤10 mmHg and no regurgitation.

DISCUSSION

The occurrence of short-term Harmony TPV25 dysfunction in multiple patients with a similar appearance of frame distortion and tissue accumulation within the inflow and valve housing portions of the device suggests that this may be an important failure mechanism for this valve. Potential causes of the observed findings are discussed. It is possible to treat this mechanism of TPV25 dysfunction with valve-in-valve implant using balloon expandable transcatheter valves.

Prosthesis Choice in Dialysis Patients Undergoing Mitral Valve Replacement

BACKGROUND

Patients with renal disease on dialysis have significant comorbidity limiting life expectancy; however, these patients may experience accelerated prosthetic valve degeneration. The purpose of this study was to examine the impact of prosthesis choice on outcomes in dialysis patients undergoing mitral valve replacement (MVR) at our high-volume academic center.

METHODS

Adults undergoing MVR were retrospectively reviewed between January 2002 and November 2019. Patients were included if they had documented renal failure and dialysis requirements before presentation. Patients were stratified by mechanical vs bioprosthetic prosthesis. Death and recurrent severe valve failure (3+ or greater) or redo mitral operation were used as primary outcomes.

RESULTS

There were 177 dialysis patients identified who underwent MVR. Of these, 118 (66.7%) received bioprosthetic valves, whereas 59 (33.3%) received mechanical valves. Those who received mechanical valves were younger (48 vs 61 years; P < .001) and had less diabetes (32% vs 51%; P = .019). Prevalence of endocarditis and atrial fibrillation was similar. Postoperative length of stay was not different between groups. Risk-adjusted hazard for 5-year mortality was similar between groups (P = .668). Early mortality was high, with both groups having <50% actuarial survival at 2 years. No differences were noted in rates of structural valve deterioration or reintervention. More stroke events were noted on follow-up in patients receiving mechanical valves (15% vs 6%; P = .041). Endocarditis was the leading reason for reintervention; 4 patients received repeated surgery for bioprosthetic valve failure.

CONCLUSIONS

MVR in dialysis patients carries significant morbidity and increased midterm mortality. Decreased life expectancy should be considered in the tailoring of prosthesis choice to dialysis-dependent patients.

Patient characteristics and long-term outcomes in patients undergoing transcatheter aortic valve implantation in a failed surgical prosthesis vs in a native valve: A Danish nationwide study

BACKGROUND

Valve-in-valve-transcatheter aortic valve implantation (TAVI) is a feasible and increasingly used treatment option for failed surgical aortic prosthesis, but data from clinical practice are limited. We aimed to examine patient characteristics and outcomes of patients undergoing TAVI in a surgival valve (valve-in-valve TAVI) compared with patients undergoing TAVI in a native valve.

METHODS

Using nationwide registries, we identified all Danish citizens, who underwent TAVI from January 1, 2008, to December 31, 2020.

RESULTS

A total of 6,070 patients undergoing TAVI were identified; 247 (4%) patients had a history of SAVR (The valve-in-valve cohort). The median age of the study population was 81 (25th-75th percentile 77-85) and 55% were men. Patients with valve-in-valve-TAVI were younger but had a greater burden of cardiovascular comorbidities compared with patients with native-valve-TAVI. Within 30 days post procedure, 11 (0.2%) and 748 (13.8%) patients who underwent valve-in-valve-TAVI and native-valve-TAVI, respectively, had a pacemaker implantation. The cumulative 30-day risk of death among patients with valve-in-valve-TAVI was 2.4% (95% CI: 1.0%-5.0%) and 2.7% (95% CI: 2.3%-3.1%) in patients with native-valve-TAVI, respectively. Correspondingly, the cumulative 5-year risk of death was 42.5% (95% CI: 34.2%-50.6%) and 44.8% (95% CI: 43.2%-46.4%), respectively. In multivariable Cox proportional hazard analysis, valve-in-valve-TAVI was not associated with a significantly different risk of death at 30 days (Hazard ratio (HR) = 0.95, 95% CI 0.41-2.19) and 5 years (HR = 0.79, 95% CI 0.62-1.00) post-TAVI compared with native-valve-TAVI.

CONCLUSIONS

TAVI in a failed surgical aortic prosthesis as compared to TAVI in a native valve, was not associated with significantly different short- and long-term mortality, suggesting that valve-in-valve-TAVI is a safe procedure.

There is Nothing More Invisible than the Obvious: A Case Summary and Literature Review

Bioprosthetic valvular failure (BVF) is a pathological entity arising from a variety of conditions affecting prosthetic heart valves. It may present with an extremely varied pattern, and the identification of the exact etiology is vital to provide a prompt and adequate treatment. It is established that infective endocarditis mainly affects patients with intracardiac devices such as pacemakers or prosthetic valves, and it represents one of the principal mechanisms of BVF. Despite its high incidence, clinical presentations may be atypical, and a close monitoring is essential to prevent catastrophic consequences. We present the case of a partial valvular bioprosthesis detachment associated with a newly formed pseudoaneurysm due to a late infective endocarditis occurred after cardiac surgery, initially manifested with negative blood cultures and clinical findings. We also try to set up a literature review of the most common causes of valvular failure and pseudoaneurysm formation.

Early Biological Valve Failure: Structural Valve Degeneration, Thrombosis, or Endocarditis?

Biological valve failure (BVF) is an inevitable condition that compromises the durability of biological heart valves (BHVs). It stems from various causes, including rejection, thrombosis, and endocarditis, leading to a critical state of valve dysfunction. Echocardiography, cardiac computed tomography, cardiac magnetic resonance, and nuclear imaging play pivotal roles in the diagnostic multimodality workup of BVF. By providing a comprehensive overview of the pathophysiology of BVF and the diagnostic approaches in different clinical scenarios, this review aims to aid clinicians in their decision-making process. The significance of early detection and appropriate management of BVF cannot be overstated, as these directly impact patients' prognosis and their overall quality of life. Ensuring timely intervention and tailored treatments will not only improve outcomes but also alleviate the burden of this condition on patients' life. By prioritizing comprehensive assessments and adopting the latest advancements in diagnostic technology, medical professionals can significantly enhance their ability to manage BVF effectively.

Transcatheter aortic valve implantation versus surgical aortic valve replacement in dialysis-dependent patients: a meta-analysis

OBJECTIVES

This meta-analysis aims to compare the clinical outcomes of transcatheter aortic valve implantation (TAVI) versus aortic valve replacement (AVR) for aortic stenosis in dialysis-dependent patients.

METHODS

Literature searches employed PubMed, Web of Science, Google Scholar and Embase to identify relevant studies. Bias-treated data were prioritized, isolated and pooled for analysis; raw data were utilized where bias-treated data were unavailable. Outcomes were analysed to assess for study data crossover.

RESULTS

Literature search identified 10 retrospective studies; following data source analysis, five studies were included. Upon pooling of bias-treated data, TAVI was significantly favoured in early mortality [odds ratio (OR), 0.42; 95% confidence interval (95% CI), 0.19-0.92; I2  = 92%; P  = 0.03], 1-year mortality (OR, 0.88; 95% CI 0.80-0.97; I2  = 0%; P  = 0.01), rates of stroke/cerebrovascular events (OR, 0.71; 95% CI 0.55-0.93; I2  = 0%; P  = 0.01) and blood transfusions (OR, 0.36; 95% CI 0.21-0.62; I2  = 86%; P  = 0.0002). Pooling demonstrated fewer new pacemaker implantations in the AVR group (OR, 3.33; 95% CI 1.94-5.73; I2  = 74%; P  ≤ 0.0001) and no difference in the rate of vascular complications (OR, 2.27; 95% CI 0.60-8.59; I2  = 83%; P  = 0.23). Analysis including raw data revealed the length of hospital stay to favour TAVI with a mean difference of -9.20 days (95% CI -15.58 to -2.82; I2  = 97%; P  = 0.005).

CONCLUSION

Bias-treated meta-analysis comparing surgical AVR and TAVI favoured TAVI in early mortality, 1-year mortality, rates of stroke/cerebrovascular events and blood transfusions. There was no difference in the rates of vascular complications; however, TAVI required more pacemaker implantations. Data pooling including raw data revealed that the length of hospital admission favours TAVI.

The Longest Known Survival of a Patient With Bioprosthetic Aortic Valve Replacement: A 42-Year Follow-Up

Aortic valve replacement (AVR) is a frequently performed procedure for treating aortic valvulopathy. AVR involves replacing the damaged aortic valve with either a mechanical or a bioprosthetic valve. While many factors are involved when selecting between the two options, age and patient preference are the deciding factors at this point. Mechanical valves demonstrate long-standing durability that overlaps with the accompanied bleeding risk due to lifetime anticoagulant therapy, making them a more favorable choice for younger patients. Bioprosthetic valves are preferred for older patients as they show a reduced risk of thrombogenicity. However, bioprosthetic valves have a higher incidence of structural valve degeneration (SVD) than mechanical valves. Our case report focuses on a 76-year-old patient who had undergone an AVR with a bioprosthetic valve at the age of 33, which has still not demonstrated any valve deterioration. As the longest known case of bioprosthetic durability, this patient provides useful data for designing bioprosthetic valves more resistant to structural degeneration and thereby better suited to younger patients or those at higher risk of bleeding.

Beyond Aortic Stenosis: Addressing the Challenges of Multivalvular Disease Assessment

Aortic stenosis (AS) can often coexist with other valvular diseases or be combined with aortic regurgitation (AR), leading to unique pathophysiological conditions. The combination of affected valves can vary widely, resulting in a lack of standardized diagnostic or therapeutic approaches. Echocardiography is crucial in assessing patients with valvular heart disease (VHD), but careful consideration of the hemodynamic interactions between combined valvular defects is necessary. This is important as it may affect the reliability of commonly used echocardiographic parameters, making the diagnosis challenging. Therefore, a multimodality imaging approach, including computed tomography or cardiac magnetic resonance, is often not just beneficial but crucial. It represents the future of diagnostics in this intricate field due to its unprecedented capacity to quantify and comprehend valvular pathology. The absence of definitive data and guidelines for the therapeutic management of AS in the context of multiple valve lesions makes this condition particularly challenging. As a result, an individualized, case-by-case approach is necessary, guided primarily by the recommendations for the predominant valve lesion. This review aims to summarize the pathophysiology of AS in the context of multiple and mixed valve disease, with a focus on the hemodynamic implications, diagnostic challenges, and therapeutic options.

Dialdehyde xanthan gum and curcumin synergistically crosslinked bioprosthetic valve leaflets with anti-thrombotic, anti-inflammatory and anti-calcification properties

Currently commercial glutaraldehyde (GA)-crosslinked bioprosthetic valve leaflets (BVLs) suffer from thromboembolic complications, calcification, and limited durability, which are the major stumbling block to wider clinical application of BVLs. Thus, developing new-style BVLs will be an urgent need to enhance the durability of BVLs and alleviate thromboembolic complications. In this study, a quick and effective collaborative strategy of the double crosslinking agents (oxidized polysaccharide and natural active crosslinking agent) was reported to realize enhanced mechanical, and structural stability, excellent hemocompatibility and anti-calcification properties of BVLs. Dialdehyde xanthan gum (AXG) exhibiting excellent stability to heat, acid-base, salt, and enzymatic hydrolysis was first introduced to crosslink decellularized porcine pericardium (D-PP) and then curcumin with good properties of anti-inflammatory, anti-coagulation, anti-liver fibrosis, and anti-atherosclerosis was used to synergistically crosslink and multi-functionalize D-PP to obtain AXG + Cur-PP. A comprehensive evaluation of structural characterization, hemocompatibility, endothelialization potential, mechanical properties and component stability showed that AXG + Cur-PP exhibited better anti-thrombotic properties and endothelialization potential, milder immune responses, excellent anti-calcification properties and enhanced mechanical properties compared with GA-crosslinked PP. Overall, this cooperative crosslinking strategy provides a novel solution to achieve BVLs with enhanced mechanical properties and excellent anti-coagulation, anti-inflammatory, anti-calcification, and the ability to promote endothelial cell proliferation.

Hemodynamic Performance of Transcatheter Aortic Valves: A Comprehensive Review

Transcatheter aortic valve implantation (TAVI) is a widely adopted treatment option for patients with severe aortic stenosis. Its popularity has grown significantly in recent years due to advancements in technology and imaging. As TAVI use is increasingly expanded to younger patients, the need for long-term assessment and durability becomes paramount. This review aims to provide an overview of the diagnostic tools to evaluate the hemodynamic performance of aortic prosthesis, with a special focus on the comparison between transcatheter and surgical aortic valves and between self-expandable and balloon-expandable valves. Moreover, the discussion will encompass how cardiovascular imaging can effectively detect long-term structural valve deterioration.

Clinical Profile and Outcomes of Patients With Pure Aortic Regurgitation Who Underwent Surgical Aortic Valve Replacement

Surgical aortic valve replacement (SAVR) remains the standard of care for patients with chronic severe aortic regurgitation (AR). The introduction of a dedicated transcatheter heart valve for AR has fueled interest in using transcatheter aortic valve replacement to treat patients with isolated AR. We aimed to characterize the profile and outcomes of patients with symptomatic severe AR who underwent isolated SAVR. We conducted a retrospective, observational study of patients who underwent isolated SAVR for symptomatic severe AR at our institution. The primary outcome was in-hospital all-cause mortality. Patients were followed up with 30-day clinical and echocardiographic assessment. A total of 979 patients who underwent SAVR for severe AR between January 2015 and June 2021 were screened for eligibility, of whom 112 patients (11.4%) underwent isolated SAVR for symptomatic severe AR and were included in this analysis. Approximately 25% of patients were deemed to be at intermediate or high risk (n = 26 of 112). The primary outcome occurred in 2.7% of patients (n = 3 of 112). In-hospital stroke occurred in 2.7% of patients (n = 3 of 112), and new-onset atrial fibrillation occurred in 32.1% (n = 36 of 112). At 30-day follow-up, all-cause mortality occurred in 3.6% of patients (n = 4 of 112), and 0.8% (1 of 112) had >mild AR. In conclusion, in a tertiary referral center, the number of patients who underwent isolated SAVR for pure AR represented a small fraction of the overall SAVR patients. The vast majority were low risk and younger when compared with patients with severe aortic stenosis. SAVR yielded excellent short-term mortality and echocardiographic improvements.

Contemporary issues and lifetime management in patients underwent transcatheter aortic valve replacement

Latest clinical trials have indicated favorable outcomes following transcatheter aortic valve replacement (TAVR) in low surgical risk patients with severe aortic stenosis. However, there are unanswered questions particularly in younger patients with longer life expectancy. While current evidence are limited to short duration of clinical follow-up, there are certain factors which may impair patients clinical outcomes and quality-of-life at long-term. Contemporary issues in the current TAVR era include prosthesis-patient mismatch, heart failure hospitalization, subclinical thrombosis, future coronary access, and valve durability. In this review, the authors review available evidence and discuss each remaining issues and theoretical treatment strategies in lifetime management of TAVR patients.

Long-term durability of self-expanding and balloon-expandable transcatheter aortic valve prostheses: UK TAVI registry

BACKGROUND

With expansion of transcatheter aortic valve implantation (TAVI) into younger patients, valve durability is critically important.

AIMS

We aimed to evaluate long-term valve function and incidence of severe structural valve deterioration (SVD) among patients ≥ 10-years post-TAVI and with echocardiographic follow-up at least 5-years postprocedure.

METHODS

Data on patients who underwent TAVI from 2007 to 2011 were obtained from the UK TAVI registry. Patients with paired echocardiograms postprocedure and ≥5-years post-TAVI were included. Severe SVD was determined according to European task force guidelines.

RESULTS

221 patients (79.4 ± 7.3 years; 53% male) were included with median echocardiographic follow-up 7.0 years (range 5-13 years). Follow-up exceeded 10 years in 43 patients (19.5%). Valve types were the supra-annular self-expanding CoreValve (SEV; n = 143, 67%), balloon-expandable SAPIEN/XT (BEV; n = 67, 31%), Portico (n = 4, 5%) and unknown (n = 7, 3%). There was no difference between postprocedure and follow-up peak gradient in the overall cohort (19.3 vs. 18.4 mmHg; p = NS) or in those with ≥10-years follow-up (21.1 vs. 21.1 mmHg; p = NS). Severe SVD occurred in 13 patients (5.9%; median 7.8-years post-TAVI). Three cases (23.1%) were due to regurgitation and 10 (76.9%) to stenosis. Valve-related reintervention/death occurred in 5 patients (2.3%). Severe SVD was more frequent with BEV than SEV (11.9% vs. 3.5%; p = 0.02), driven by a difference in patients treated with small valves (BEV 28.6% vs. SEV 3.0%; p < 0.01).

CONCLUSIONS

Hemodynamic function of transcatheter heart valves remains stable up to more than 10 years post-TAVI. Severe SVD occurred in 5.9%, and valve-related death/reintervention in 2.3%. Severe SVD was more common with BEV than SEV.

Polymeric prosthetic heart valves: A review of current technologies and future directions

Valvular heart disease is an important source of cardiovascular morbidity and mortality. Current prosthetic valve replacement options, such as bioprosthetic and mechanical heart valves are limited by structural valve degeneration requiring reoperation or the need for lifelong anticoagulation. Several new polymer technologies have been developed in recent years in the hope of creating an ideal polymeric heart valve substitute that overcomes these limitations. These compounds and valve devices are in various stages of research and development and have unique strengths and limitations inherent to their properties. This review summarizes the current literature available for the latest polymer heart valve technologies and compares important characteristics necessary for a successful valve replacement therapy, including hydrodynamic performance, thrombogenicity, hemocompatibility, long-term durability, calcification, and transcatheter application. The latter portion of this review summarizes the currently available clinical outcomes data regarding polymeric heart valves and discusses future directions of research.

Comparison of in-hospital outcomes and long-term survival for valve-in-valve transcatheter aortic valve replacement versus the benchmark native valve transcatheter aortic valve replacement procedure

Background

In recent years, the number of patients with failed surgically implanted aortic bioprostheses and the number of candidates for valve-in-valve transcatheter aortic valve replacement (VIV-TAVR) have been increasing.

Objectives

The purpose of this study is to evaluate the efficacy, safety, and long-term survival outcomes of VIV-TAVR compared with the benchmark native valve transcatheter aortic valve replacement (NV-TAVR).

Methods

A cohort study was conducted on patients who underwent TAVR in the department of cardiology at Toulouse University Hospital, Rangueil, France between January 2016 and January 2020. The study population was divided into two groups: NV-TAVR (N = 1589) and VIV-TAVR (N = 69). Baseline characteristics, procedural data, in-hospital outcomes, and long-term survival outcomes were observed.

Results

In comparison with NV-TAVR, there are no differences in TAVR success rate (98.6 vs. 98.8%, p = 1), per-TAVR complications (p = 0.473), and length of hospital stay (7.5 ± 50.7 vs. 4.4 ± 2.8, p = 0.612). The prevalence of in-hospital adverse outcomes did not differ among study groups, including acute heart failure (1.4 vs. 1.1%), acute kidney injury (2.6, 1.4%), stroke (0 vs. 1.8%, p = 0.630), vascular complications (p = 0.307), bleeding events (0.617), and death (1.4 vs. 2.6%). VIV-TAVR was associated with a higher residual aortic gradient [OR = 1.139, 95%CI (1.097-1.182), p = 0.001] and a lower requirement for permanent pacemaker implantation [OR = 0.235 95%CI (0.056-0.990), p = 0.048]. Over a mean follow-up period of 3.44 ± 1.67 years, no significant difference in survival outcomes has been observed (p = 0.074).

Conclusion

VIV-TAVR shares the safety and efficacy profile of NV-TAVR. It also represents a better early outcome but a higher non-significant long-term mortality rate.

Transcatheter Aortic Valve Implantation: Long-Term Outcomes and Durability

Transcatheter aortic valve implantation (TAVI) has become the standard of care in symptomatic older patients with severe aortic stenosis regardless of surgical risk. With the development of newer generation transcatheter bioprostheses, improved delivery systems, better preprocedure planning with imaging guidance, increased operator experience, shorter hospital length of stay, and low short- and mid-term complication rates, TAVI is gaining popularity among younger patients at low or intermediate surgical risk. Long-term outcomes and durability of transcatheter heart valves have become substantially important for this younger population due to their longer life expectancy. The lack of standardized definitions of bioprosthetic valve dysfunction and disagreement about how to account for the competing risks made comparison of transcatheter heart valves with surgical bioprostheses challenging until recently. In this review, the authors discuss the mid- to long-term (≥ 5 years) clinical outcomes observed in the landmark TAVI trials and analyze the available long-term durability data emphasizing the importance of using standardized definitions of bioprosthetic valve dysfunction.

TAVI Under Pressure: Intra-balloon Pressure Profiles During Balloon-Expandable TAVR-First Data from a Feasibility Study

Our study investigated the feasibility to measure pressure profiles inside the inflation balloon during direct implantation of Edwards Sapien 3 ultra-prostheses using an additional syringe with a digital pressure read-out. Pressure profiles of 15 patients for 26 mm valve size were analyzed. Uniform patterns were found for 5 patients similar to those of previously acquired in vitro curves. 10 patients showed strikingly different pressure profiles compared to the above-mentioned group, marked by an earlier pressure increase, single or multiple pressure drops or higher overall pressure. Measuring the percentage of under-expansion of the prostheses, using calibrated angiographic projections revealed a significant difference between both groups. Our data raises the hypothesis that the acquisition of pressure profiles might help to better understand not only the implantation procedure itself but also the highly individual patient-device interaction, offering new information and a new perspective on optimization of TAVR implantation in the future.

Advances in Multifunctional Bioactive Coatings for Metallic Bone Implants

To fix the bone in orthopedics, it is almost always necessary to use implants. Metals provide the needed physical and mechanical properties for load-bearing applications. Although widely used as biomedical materials for the replacement of hard tissue, metallic implants still confront challenges, among which the foremost is their low biocompatibility. Some of them also suffer from excessive wear, low corrosion resistance, infections and shielding stress. To address these issues, various coatings have been applied to enhance their in vitro and in vivo performance. When merged with the beneficial properties of various bio-ceramic or polymer coatings remarkable bioactive, osteogenic, antibacterial, or biodegradable composite implants can be created. In this review, bioactive and high-performance coatings for metallic bone implants are systematically reviewed and their biocompatibility is discussed. Updates in coating materials and formulations for metallic implants, as well as their production routes, have been provided. The ways of improving the bioactive coating performance by incorporating bioactive moieties such as growth factors, osteogenic factors, immunomodulatory factors, antibiotics, or other drugs that are locally released in a controlled manner have also been addressed.

Review of bioprosthetic structural valve deterioration: Patient or valve?

BACKGROUND

With guidelines progressively recommending bioprosthetic aortic valves in younger patients, a greater emphasis is placed on structural valve deterioration (SVD) as an important clinical endpoint for both transcatheter and surgically implanted valves. However, SVD of bioprosthetic valves is a complex entity with varying definitions in the literature and a multifaceted pathogenesis.

AIM

This review first aims to establish the most updated definitions of SVD as per the literature. We then explore the patient- and valve-related factors that play the greatest roles in facilitating early SVD.

METHODS

A PubMed literature review was conducted to identify the relevant research in this field within the past two decades.

CONCLUSION

Increasing rates of obesity and metabolic syndrome pose a significant risk to the longevity of bioprosthetic valves. Additionally, externally mounted valves have proven to sacrifice durability for superior haemodynamics. Bioprosthetic SVD continues to be a multifactorial issue that will require various patient- and valve-related factors to be addressed.

Structural valve deterioration of bioprosthesis in the aortic position: A single-center experience

BACKGROUND

Aortic valve replacement (AVR) is one of the most common open-heart surgical procedures. The durability of the tissue valve in the aortic position is crucial in AVR and transcatheter AVR. We reviewed structural valve deterioration using echocardiographic follow-up in three types of surgical aortic tissue valves.

METHODS

A retrospective analysis was conducted where hemodynamic deterioration was evaluated and compared using transthoracic echocardiography, including pressure gradients and effective orifice area. Kaplan-Meier analyses were used to summarize the time to failure.

RESULTS

The study included 133 Trifecta, 156 Epic, and 321 Magna Ease valves. Seventy-six percent (1941/2551) of patients had to be excluded due to insufficient echo data. Through univariate analysis, 34% (216/610) of valves met deterioration criteria after 24 months. Unadjusted survival curves showed a significant difference between valves (p ≤ .001), with a longer mean time to deterioration for the Magna Ease versus Trifecta and Epic of 68.9 versus 50.1 and 38.2 months, respectively. A Cox proportional hazard analysis found worse hazard ratios of 1.69 (p ≤ .04) and 2.4 (p ≤ .01) for Trifecta versus Magna and Epic versus Trifecta, respectively.

CONCLUSION

All three valve types demonstrated structural valve deterioration on echocardiographic follow-up with significant differences in rate. The Magna Ease appeared to have the highest durability, and the Epic the lowest. Further investigation is warranted to confirm the results in a larger multicenter study.

The search for optimal antithrombotic therapy in transcatheter aortic valve implantation: facts and uncertainties

Transcatheter aortic valve implantation (TAVI) is a minimally invasive procedure, which is used frequently in patients with symptomatic severe aortic valve stenosis. Most patients undergoing TAVI are over 80 years of age with a high bleeding as well as thrombotic risk. Despite the increasing safety of the procedure, thromboembolic events [stroke, (subclinical) valve thrombosis] remain prevalent. As a consequence, antithrombotic prophylaxis is routinely used and only recently new data on the efficacy and safety of antithrombotic drugs has become available. On the other hand, these antithrombotic drugs increase bleeding in a population with unique aortic stenosis-related bleeding characteristics (such as acquired von Willebrand factor defect and angiodysplasia). In this review, we discuss the impact of thromboembolic and bleeding events, the current optimal antithrombotic therapy based on registries and recent randomized controlled trials, as well as try to give a practical guide how to treat these high-risk patients. Finally, we discuss knowledge gaps and future research needed to fill these gaps.

Polyphenol based hybrid nano-aggregates modified collagen fibers of biological valve leaflets to achieve enhanced mechanical, anticoagulation and anti-calcification properties

Glutaraldehyde (Glut)-crosslinked porcine pericardium and bovine pericardium are mainly consisted of collagen and widely used for the preparation of heterogenous bioprosthetic heart valves (BHV), which play an important role in the replacement therapy of severe valvular heart disease, while their durability is limited by degeneration due to calcification, thrombus, endothelialization difficulty and prosthetic valve endocarditis. Herein, we develop a novel BHV, namely, TPly-BP, based on natural tannic acid and polylysine to improve the durability of Glut crosslinked bovine pericardium (Glut-BP). Impressively, tannic acid and polylysine could form nanoaggregates via multiple hydrogen bonds and covalent bonds, and the introduction of nanoaggregates not only improved the mechanical properties and collagen stability but also endowed TPly-BP with good biocompatibility and hemocompatibility. Compared to Glut-BP, TPly-BP showed significantly reduced cytotoxicity, improved endothelial cell adhesion, a low hemolysis ratio and obviously reduced platelet adhesion. Importantly, TPly-BP exhibited great antibacterial and in vivo anti-calcification ability, which was expected to improve the in vivo durability of BHVs. These results suggested that TPly-BP would be a potential candidate for BHV.

Graphical abstract

Inhibition of advanced glycation end product formation and serum protein infiltration in bioprosthetic heart valve leaflets: Investigations of anti-glycation agents and anticalcification interactions with ethanol pretreatment

Bioprosthetic heart valves (BHV) fabricated from heterograft tissue, such as glutaraldehyde pretreated bovine pericardium (BP), are the most frequently used heart valve replacements. BHV durability is limited by structural valve degeneration (SVD), mechanistically associated with calcification, advanced glycation end products (AGE), and serum protein infiltration. We investigated the hypothesis that anti-AGE agents, Aminoguanidine, Pyridoxamine [PYR], and N-Acetylcysteine could mitigate AGE-serum protein SVD mechanisms in vitro and in vivo, and that these agents could mitigate calcification or demonstrate anti-calcification interactions with BP pretreatment with ethanol. In vitro, each of these agents significantly inhibited AGE-serum protein infiltration in BP. However, in 28-day rat subdermal BP implants only orally administered PYR demonstrated significant inhibition of AGE and serum protein uptake. Furthermore, BP PYR preincubation of BP mitigated AGE-serum protein SVD mechanisms in vitro, and demonstrated mitigation of both AGE-serum protein uptake and reduced calcification in vivo in 28-day rat subdermal BP explants. Inhibition of BP calcification as well as inhibition of AGE-serum protein infiltration was observed in 28-day rat subdermal BP explants pretreated with ethanol followed by PYR preincubation. In conclusion, AGE-serum protein and calcification SVD pathophysiology are significantly mitigated by both PYR oral therapy and PYR and ethanol pretreatment of BP.

Functional performance of eight small surgical aortic valve bioprostheses: An in vitro study

OBJECTIVES

Selection of a surgical aortic valve bioprosthesis (SAV) model for treatment of aortic valve disease remains controversial. The aim of this study was to characterize the functional performance of eight SAV models in a standardized in vitro setting.

METHODS

The hydrodynamic performance of eight SAVs with labelled size 21 mm (Avalus™, Hancock® II, Mosaic® UltraTM, Perimount®, Perimount® Magna Ease, EpicTM Supra, Trifecta™ GT; Freestyle®) was investigated in a pulse duplicator. Transvalvular pressure gradients and effective orifice area (EOA) were recorded. The geometrical orifice area (GOA) and physical dimensions of the valves were determined, and new functional dimensions were introduced.

RESULTS

Mean pressure gradient (MPG) and EOA differed significantly between the analyzed SAVs. The Epic presented with the lowest EOA and highest MPG, while the Trifecta showed the highest EOA and the lowest MPG. We introduce a useful way to determine the minimal internal diameter and a new measure termed 'relative orifice area' to characterize a valve's performance.

CONCLUSIONS

SAVs showed significant differences in their hydrodynamic performance despite the same label size. This finding was related to the construction of the valves. We introduce a new measure that characterizes the functional performance of a valve model and size for treatment of an aortic annulus of a specific size. Our data emphasize that SAV selection should carefully be done using an individual patient approach and that future research is necessary to improve the current generation of SAVs.

Bioprosthetic Aortic Valve Hemodynamics: Definitions, Outcomes, and Evidence Gaps: JACC State-of-the-Art Review

A virtual workshop was organized by the Heart Valve Collaboratory to identify areas of expert consensus, areas of disagreement, and evidence gaps related to bioprosthetic aortic valve hemodynamics. Impaired functional performance of bioprosthetic aortic valve replacement is associated with adverse patient outcomes; however, this assessment is complicated by the lack of standardization for labelling, definitions, and measurement techniques, both after surgical and transcatheter valve replacement. Echocardiography remains the standard assessment methodology because of its ease of performance, widespread availability, ability to do serial measurements over time, and correlation with outcomes. Management of a high gradient after replacement requires integration of the patient's clinical status, physical examination, and multimodality imaging in addition to shared patient decisions regarding treatment options. Future priorities that are underway include efforts to standardize prosthesis sizing and labelling for both surgical and transcatheter valves as well as trials to characterize the consequences of adverse hemodynamics.

In-Hospital Outcomes and Predictors of Mortality for Redo Surgical Mitral Valve Replacement Versus Transcatheter Mitral Valve-in-Valve Replacement

Durability is a major limitation with bioprosthetic heart valves. For mitral valve prosthesis dysfunction, redo surgical mitral valve replacement (rSMVR) has been the mainstay of treatment; however, transcatheter mitral valve-in-valve replacement (mViV) has emerged as a viable alternative. Data comparing these procedures remains limited; therefore, we sought to compare the real-world in-hospital mortality, likelihood of adverse peri-operative outcomes, and predictors of mortality between rSMVR versus mViV using the National Inpatient Sample. During the study period, a weighted total of 1,890 patients (78%) underwent rSMVR, and 520 (22%) underwent mViV. After propensity matching, there were 310 patients in each cohort. There was no statistically significant difference in mortality with these procedures (odds ratio 1.53; 95% confidence interval 0.67 to 3.45; p = 0.31). rSMVR was associated with increased length of hospitalization (13 vs 7.5 days; p <0.001), increased medical costs ($324,124 vs $241,147; p <0.001), and increased peri-operative complications compared with mViV. Predictors of mortality unique to rSMVR were age >75 years, cirrhosis, sleep apnea, malnourishment/low body mass index, and obesity, signalizing greater suitability for mViV in these populations.

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.

A Novel Crosslinking Method for Improving the Anti-Calcification Ability and Extracellular Matrix Stability in Transcatheter Heart Valves

More than 200,000 patients with aortic diseases worldwide undergo surgical valve replacement each year, and transcatheter heart valves (THV) have been more widely used than ever before. However, THV made by the glutaraldehyde (Glut) crosslinking method has the disadvantage of being prone to calcification, which significantly reduces the durability of biomaterials. In this study, we applied a novel crosslinking method using ribose in THV for the first time, which can decrease calcification and increase the stability of the extracellular matrix (ECM). We incubated the bovine pericardium (BP) in ribose solution at 37°C by shaking for 12 days and confirmed that the structure of the BP was more compact than that of the Glut group. Moreover, the ribose method remarkably enhanced the biomechanical properties and provided reliable resistance to enzymatic degradation and satisfactory cellular compatibility in THV. When the BP was implanted subcutaneously in vivo, we demonstrated that ECM components were preserved more completely, especially in elastin, and the immune-inflammatory response was more moderate than that in the Glut treatment group. Finally, the ribose-cross-linked materials showed better anti-calcification potential and improved durability of THV than Glut-cross-linked materials.

Impact of postoperative patient-prosthesis mismatch as a risk factor for early structural valve deterioration after aortic valve replacement with Trifecta bioprosthesis

BACKGROUND

Several studies have reported high rates of structural valve deterioration (SVD) in the Trifecta valves. Herein, we analyzed the midterm results of the Trifecta valve and risk factors for early SVD.

METHODS

We retrospectively reviewed the records of 110 patients who had undergone Trifecta implantation between January 2012 and December 2017.

RESULTS

We encountered seven cases of Trifecta valve failure. We performed a redo aortic valve replacement in five patients and a transcatheter aortic valve replacement in two patients. The SVD rate was 4.8% at 5 years and 6.6% at 7 years. The mean pressure gradient and peak velocity on the first postoperative echocardiogram in patients with SVD were higher than those in patients without SVD. The SVD rates with and without patient-prosthesis mismatch (PPM) were 2.8% and 12.6% at 5 years and 2.8% and 20.0% at 7 years. PPM is a risk factor for SVD. Noncoronary cusp tears were observed in all patients who had undergone redo surgery.

CONCLUSIONS

The most common cause of SVD was noncoronary cusp tear. Patients with PPM are at high risk of developing SVD.