Durability and Clinical Outcomes of Transcatheter Aortic Valve Replacement for Failed Surgical Bioprostheses

Valve-in-Valve Transcatheter Aortic Valve Replacement Versus Redo-Surgical Aortic Valve Replacement in Patients With Aortic Stenosis: A Systematic Review and Meta-analysis

Aortic stenosis is a common and significant valve condition requiring bioprosthetic heart valves with transcatheter aortic valve replacement (TAVR) being strongly recommended for high-risk patients or patients over 75 years. This meta-analysis aimed to pool existing data on postprocedural clinical as well as echocardiographic outcomes comparing valve-in-valve (ViV)-TAVR to redo-surgical aortic valve replacement to assess the short-term and medium-term outcomes for both treatment methods. A systematic literature search on Cochrane Central, Scopus, and Medline (PubMed interface) electronic databases from inception to August 2023. We used odds ratios (OR) for dichotomous outcomes and mean differences (MD) for continuous outcomes. Twenty-four studies (25,216 patients) were pooled with a mean follow-up of 16.4 months. The analysis revealed that ViV-TAVR group showed a significant reduction in 30-day mortality (OR 0.50, 95% confidence interval [CI] 0.43 to 0.58, p <0.00001), new-onset atrial fibrillation (OR 0.34, 95% CI 0.17 to 0.67, p = 0.002), major bleeding event (OR 0.28, 95% CI 0.17 to 0.45, p <0.00001) and lower rate of device success (OR 0.25, 95% CI 0.12 to 0.53, p = 0.0003). There were no significant differences between either group when assessing 1-year mortality, stroke, myocardial infarction, postoperative left ventricular ejection fraction, and effective orifice area. ViV-TAVR cohort showed a significantly increased incidence of paravalvular leaks, aortic regurgitation, and increased mean aortic valve gradient. ViV-TAVR is a viable short-term option for older patients with high co-morbidities and operative risks, reducing perioperative complications and improving 30-day mortality with no significant cardiovascular adverse events. However, both treatment methods present similar results on short-term to medium-term complications assessment.

Aortic Valve-in-Valve Procedures: Challenges and Future Directions

Aortic valve-in-valve (ViV) procedures are increasingly performed for the treatment of surgical bioprosthetic valve failure in patients at intermediate to high surgical risk. Although ViV procedures offer indisputable benefits in terms of procedural time, in-hospital length of stay, and avoidance of surgical complications, they also present unique challenges. Growing awareness of the technical difficulties and potential threats associated with ViV procedures mandates careful preprocedural planning. This review article offers an overview of the current state-of-the-art ViV procedures, with focus on patient and device selection, procedural planning, potential complications, and long-term outcomes. Finally, it discusses current research efforts and future directions aimed at improving ViV procedural success and patient outcomes.

Transcatheter or Surgical Replacement for Failed Bioprosthetic Aortic Valves

Importance

The use of valve-in-valve (ViV) transcatheter aortic valve replacement (TAVR) has been rapidly expanding as an alternative treatment to redo surgical aortic valve replacement (SAVR) for failed bioprosthetic valves despite limited long-term data.

Objective

To assess mortality and morbidity in patients undergoing intervention for failed bioprosthetic SAVR.

Design, Setting, and Participants

This was a retrospective population-based cohort analysis conducted between January 1, 2015, and December 31, 2020, with a median (IQR) follow-up time of 2.3 (1.1-4.0) years. A total of 1771 patients with a history of bioprosthetic SAVR who underwent ViV-TAVR or redo SAVR in California, New York, and New Jersey were included. Data were obtained from the California Department of Health Care Access and Information, the New York Statewide Planning and Research Cooperative System, and the New Jersey Discharge Data Collection System. Exclusion criteria included undergoing TAVR or redo SAVR within 5 years from initial SAVR, as well as infective endocarditis, concomitant surgical procedures, and out-of-state residency. Propensity matching yielded 375 patient pairs. Data were analyzed from January to December 2023.

Interventions

ViV-TAVR vs redo SAVR.

Main Outcomes and Measurements

The primary outcome was all-cause mortality. Secondary outcomes were stroke, heart failure hospitalization, reoperation, major bleeding, acute kidney failure, new pacemaker insertion, and infective endocarditis.

Results

From 2015 through 2020, the proportion of patients undergoing ViV-TAVR vs redo SAVR increased from 159 of 451 (35.3%) to 498 or 797 (62.5%). Of 1771 participants, 653 (36.9%) were female, and the mean (SD) age was 74.4 (11.3) years. Periprocedural mortality and stroke rates were similar between propensity-matched groups. The ViV-TAVR group had lower periprocedural rates of major bleeding (2.4% vs 5.1%; P = .05), acute kidney failure (1.3% vs 7.2%; P < .001), and new pacemaker implantations (3.5% vs 10.9%; P < .001). The 5-year all-cause mortality rate was 23.4% (95% CI, 15.7-34.1) in the ViV-TAVR group and 13.3% (95% CI, 9.2-18.9) in the redo SAVR group. In a landmark analysis, no difference in mortality was observed up to 2 years (hazard ratio, 1.03; 95% CI, 0.59-1.78), but after 2 years, ViV-TAVR was associated with higher mortality (hazard ratio, 2.97; 95% CI, 1.18-7.47) as well as with a higher incidence of heart failure hospitalization (hazard ratio, 3.81; 95% CI, 1.57-9.22). There were no differences in 5-year incidence of stroke, reoperation, major bleeding, or infective endocarditis.

Conclusions and Relevance

Compared with redo SAVR, ViV-TAVR was associated with a lower incidence of periprocedural complications and a similar incidence of all-cause mortality through 2 years' follow-up. However, ViV-TAVR was associated with higher rates of late mortality and heart failure hospitalization. These findings may be influenced by residual confounding and require adjudication in a randomized clinical trial.

Five-Year Follow-Up from the CoreValve Expanded Use Transcatheter Aortic Valve-in-Surgical Aortic Valve Study

Transcatheter aortic valve replacement (TAVR) provides an option for extreme-risk patients who underwent reoperation for a failed surgical aortic bioprosthesis. Long-term data on patients who underwent TAVR within a failed surgical aortic valve (TAV-in-SAV) are limited. The CoreValve Expanded Use Study evaluated patients at extreme surgical risk who underwent TAV-in-SAV. Outcomes at 5 years were analyzed by SAV failure mode (stenosis, regurgitation, or combined). Echocardiographic outcomes are site-reported. TAV-in-SAV was attempted in 226 patients with a mean age of 76.7 ± 10.8 years; 63.3% were male, the Society of Thoracic Surgeons predicted risk of mortality score was 9.0 ± 6.7%, and 87.5% had a New York Heart Association classification III or IV symptoms. Most of the failed surgical bioprostheses were stented (81.9%), with an average implant duration of 10.2 ± 4.3 years. The 5-year all-cause mortality or major stroke rate was 47.2% in all patients; 54.4% in the stenosis, 37.6% in the regurgitation, and 38.0% in the combined groups (p = 0.046). At 5 years, all-cause mortality was higher in patients with versus without 30-day severe prosthesis-patient mismatch (51.7% vs 38.3%, p = 0.026). The overall aortic valve reintervention rate was 5.9%; highest in the regurgitation group (12.6%). The mean aortic valve gradient was 14.1 ± 9.8 mm Hg and effective orifice area was 1.57 ± 0.70 at 5 years. Few patients had >mild paravalvular regurgitation at 5 years (5.5% moderate, 0.0% severe). TAV-in-SAV with supra-annular, self-expanding TAVR continues to represent a safe and lasting intermediate option for extreme-risk patients who have appropriate sizing of the preexisting failed surgical valve. Clinical and hemodynamic outcomes were stable through 5 years.

Outcomes of Surgical Bioprosthetic Aortic Valve Replacement in Patients Aged ≤65 and >65 Years

BACKGROUND

Implantation of a bioprosthetic valve is a reasonable choice for patients aged > 65 years. For middle-aged patients there is less certainty about whether a mechanical or bioprosthetic valve is best.

METHODS

The Pericardial Surgical Aortic Valve Replacement (PERIGON) Pivotal Trial is evaluating the safety and efficacy of the Avalus bioprosthesis (Medtronic). We evaluated clinical and echocardiographic outcomes through 5 years of follow-up, stratified by age ≤ 65 and >65 years.

RESULTS

Two hundred seventy-one patients (24.2%) were ≤65 years old and 847 (75.8%) >65 years old. Most patients in both groups were men (217 [80.1%] vs 623 [73.6%], respectively; P = .031). Younger patients had a lower Society of Thoracic Surgeons risk of mortality (1.1% ± 0.9% vs 2.2% ± 1.4%, P < .001), better baseline New York Heart Association class (P = .004), and fewer comorbidities than older patients. At 5 years mortality was lower among younger than older patients (5.3% vs 14.0%, P < .001) and no cases of structural valve deterioration occurred in either group. Effective orifice area was similar between age groups (P = .11), and mean gradient was 13.9 ± 5.4 vs 12.0 ± 4.1 mm Hg (P < .001). Multivariable linear regression identified several parameters associated with mean aortic gradient at 5 years, including baseline age and mean aortic gradient, discharge stroke volume index and EOA, and implanted valve size. Ninety-five percent of patients were in New York Heart Association class I/II through 5 years in both age groups (P = .85).

CONCLUSIONS

Findings from this analysis demonstrate satisfactory safety, hemodynamic performance, and durability of the Avalus bioprosthesis through a 5-year follow-up in patients aged ≤ 65 and >65 years.

Preoperative hypomagnesemia as a possible predictive factor for postoperative increase of transvalvular pressure gradient in hemodialysis patients treated with transcatheter aortic valve implantation

BACKGROUND

Patients undergoing maintenance hemodialysis (HD) with severe aortic stenosis are at a high risk for bioprosthetic valve dysfunction after transcatheter aortic valve implantation (TAVI). Currently, preoperative factors that predict the occurrence of valve dysfunction after TAVI on HD patients remain to be elucidated. The aim of this study is to analyze the association between preoperative clinical factors and valve stenosis after TAVI on HD patients.

METHODS

Twenty-four of HD patients who underwent TAVI at our institution between April 2012 and January 2016 were analyzed. The mean aortic transvalvular pressure gradient (MPG) and effective orifice area index (EOAi) were assessed by serial echocardiography. Associations between preoperative clinical factors and time-series changes in MPG were examined using mixed-effects linear regression model for repeated measures.

RESULTS

Three patients developed severe structural valve deterioration with calcific valve stenosis requiring reoperation. A multivariate linear mixed-effects model showed that lower serum magnesium (sMg) levels were associated with the increase of MPG after TAVI (beta-coefficient = 0.019, p = 0.03). No correlation was observed with serum calcium, phosphorus, or intact parathyroid hormone. Time-series changes of MPG and EOAi had significant difference between lower and higher sMg group. All 3 of the patients who underwent reoperation showed lower preoperative sMgs.

CONCLUSION

Among bone-mineral metabolism markers, preoperative hypomagnesemia was associated with the increase of MPG after TAVI, suggesting that hypomagnesemia could predict post-TAVI valve dysfunction in HD patients. Further studies with larger sample sizes are warranted.

Hemodynamic follow-up after valve-in-valve TAVR for failed aortic bioprosthesis

BACKGROUND

"valve-in-valve" TAVR (VIV-TAVR) is established and provides good initial clinical and hemodynamic outcomes. Lacking long-term durability data baffle the expand to lower risk patients. For those purposes, the present study adds a hemodynamic 3-years follow-up.

METHODS

A total of 77 patients underwent VIV-TAVR for failing aortic bioprosthesis during a 7-years period. Predominant mode of failure was stenosis in 87.0%. Patients had a mean age of 79.4 ± 5.8 years and a logistic EuroSCORE of 30.8 ± 15.7%. The Society of Thoracic Surgeons-PROM averaged 5.79 ± 2.63%. Clinical results and hemodynamic outcomes are reported for 30-days, 1-, 2-, and 3-years. Completeness of follow-up was 100% with 44 patients at risk after 3-years. Follow-up ranged up to 7.1 years.

RESULTS

Majority of the surgical valves were stented (94.8%) with a mean labeled size of 23.1 ± 2.3 mm and true-ID of 20.4 ± 2.6 mm. A true-ID ≤21 mm had 58.4% of the patients. Self-expanding valves were implanted in 68.8% (mean labeled size 24.1 ± 1.8 mm) and balloon-expanded in 31.2% (mean size 24.1 ± 1.8 mm). No patient died intraoperatively. Hospital mortality was 1.3% and three-years survival 57.1%. All patients experienced an initial significant dPmean-reduction to 16.8 ± 7.1 mmHg. After 3-years mean dPmean raised to 26.0 ± 12.2 mmHg. This observation was independent from true-ID or type of transcatheter aortic valve replacement (TAVR)-prosthesis. Patients with a true-ID ≤21 mm had a higher initial (18.3 ± 5.3 vs. 14.9 ± 7.1 mmHg; p = .005) and dPmean after 1-year (29.2 ± 8.2 vs. 13.0 ± 6.7 mmHg; p = .004). There were no significant differences in survival.

CONCLUSIONS

VIV-TAVR is safe and effective in the early period. In surgical valves with a true-ID ≤21 mm inferior hemodynamic and survival outcomes must be expected. Nonetheless, also patients with larger true-IDs showed steadily increasing transvalvular gradients. This raises concern about durability.

Surgical versus transcatheter aortic valve replacement: Impact of patient-prosthesis mismatch on outcomes

BACKGROUND

The hemodynamics of most prosthetic valves are often inferior to that of the normal native valve, and a significant proportion of patients undergoing surgical (SAVR) or transcatheter aortic valve replacement (TAVR) have high residual transaortic pressure gradients due to prosthesis-patient mismatch (PPM). As the experience with TAVR has increased and long-term outcomes are reported, a close look at the PPM literature is required in light of new evidence.

METHODS

For this review, we searched the Embase, Medline, and Cochrane databases from 2000 to 2022. Articles reporting PPM as an outcome following aortic valve replacements were identified and reviewed.

RESULTS

The impact of PPM on clinical outcomes in aortic valve replacement has not been clear as multiple studies failed to report PPM incidence. However, the PPM outcomes after SAVR vary more widely than after TAVR, ranging from 8% to 80% in SAVR and from 24% to 35% in TAVR. Incidence of severe PPM following redo SAVR ranges from 2% to 9% and following valve-in-valve TAVR is from 14% to 33%, however, while PPM is higher in valve-in-valve TAVR, patients had better survival rates.

CONCLUSIONS

The gap between valve performance and clinical outcomes in SAVR and TAVR could be reduced by carefully selecting patients for either treatment option. Understanding predictors of PPM can add to the safety, effectiveness, and increased survival benefit of both SAVR and TAVR.

Valve-in-valve transcatheter aortic valve replacement or re-surgical aortic valve replacement in degenerated bioprostheses: A systematic review and meta-analysis of short and midterm results

INTRODUCTION

Despite limited to short and midterm outcomes, valve-in-valve (ViV) transcatheter aortic valve implantation (TAVI) has emerged as a valid alternative to re-surgical aortic valve replacement (re-SAVR) for high- and intermediate-risk patients with degenerated surgical bioprosthesis.

METHODS

All studies comparing multivariate adjustment between ViV TAVI and re-SAVR were screened. The primary end-points were all-cause and cardiovascular (CV) mortality at 30 days and at Midterm follow-up. Short-term complications were the secondary endpoints.

RESULTS

We obtained data from 11 studies, encompassing 8570 patients, 4224 undergoing ViV TAVI, and 4346 re-SAVR. Four studies included intermediate-risk patients and seven high-risk patients. 30-day all-cause and CV mortality were significantly lower in ViV (odds ratio [OR] 0.43, 95% confidence intervals [CIs] 0.29-0.64 and OR 0.44, 0.26-0.73 respectively), while after a mean follow-up of 717 (180-1825) days, there was no difference between the two groups (OR 1.04, 0.87-1.25 and OR 1.05, 0.78-1.43, respectively). The risk of stroke (OR 1.03, 0.59-1.82), MI (OR 0.70, 0.34-1.44), major vascular complications (OR 0.92, 0.50-1.67), and permanent pacemaker implantation (OR 0.67, 0.36-1.25) at 30 days did not differ, while major bleedings and new-onset atrial fibrillation were significantly lower in ViV patients (OR 0.41, 0.25-0.67 and OR 0.23, 0.12-0.42, respectively, all 95% CIs).

CONCLUSIONS

In high- and intermediate-risk patients with degenerated surgical bioprostheses, ViV TAVI is associated with reduced short-term mortality, compared with re-SAVR. Nevertheless, no differences were found in all-cause and CV mortality at midterm follow-up. PROSPERO CRD42021226488.

Trans-Catheter Valve-in-Valve Implantation for the Treatment of Aortic Bioprosthetic Valve Failure

Aortic valve-in-valve (ViV) procedure is a valid treatment option for patients affected by bioprosthetic heart valve (BHV) degeneration. However, ViV implantation is technically more challenging compared to native trans-catheter aortic valve replacement (TAVR). A deep knowledge of the mechanism and features of the failed BHV is pivotal to plan an adequate procedure. Multimodal imaging is fundamental in the diagnostic and pre-procedural phases. The main challenges associated with ViV TAVR consist of a higher risk of coronary obstruction, severe post-procedural patient-prosthesis mismatch, and a difficult coronary re-access. In this review, we describe the principles of ViV TAVR.

Outcomes after transcatheter valve-in-valve implantation using a balloon-expandable Edwards Sapien valve in patients with degenerated Freestyle aortic bioprosthesis

Background

Transcatheter aortic valve-in-valve implantation (ViV TAVI) in degenerated Medtronic Freestyle aortic bioprosthesis (FSB) has been reported as being technically challenging. This study sought to evaluate procedural data and outcomes after ViV TAVI using a balloon-expandable Edwards valve in patients with failed FSB.

Methods

Between August 2014 and December 2020, twenty-seven consecutive patients underwent ViV TAVI for symptomatic FSB failure at our institution using a Sapien XT (n=1) and Sapien 3 (n=26) valve, respectively. Endpoints were defined according to the Valve Academic Research Consortium-2 (VARC-2) criteria and were retrospectively analyzed.

Results

Mean patient age was 75.7±8.2 years (female n=5, male n=22); Society of Thoracic Surgeons Predicted Risk of Mortality score was 7.3%±6.2%. ViV implantation with correct positioning of the Edwards Sapien valve within the FSB was successful in all cases. Intraprocedural transesophageal echocardiography revealed none/trace paravalvular regurgitation in twenty-five patients (92.6%), mild paravalvular regurgitation was present in two patients (7.4%). Neither of the patients had a mean gradient ≥20.0 mmHg excluding significant patient-prosthesis mismatch. Three early deaths (≤thirty days) occurred resulting in a device success rate of 88.8%. One-year and three-year survival rates for patients alive beyond day thirty after ViV TAVI were 95.8% and 70.0%, respectively.

Conclusions

ViV TAVI with Edwards Sapien valves lead to acceptable functional results in high-risk patients with degenerated FSB but early complications must be considered particularly during hospital stay.

Transcatheter valve-in-valve implantation in degenerated surgical aortic and mitral bioprosthesis: Current state and future perspectives

The use of bioprosthetic valves for treating patients with severe valve disease has increased over the last 2 decades, and, as a consequence, a growing number of patients with failing surgical bioprosthesis is expected in the near future. In this setting, valve-in-valve (ViV) transcatheter aortic/mitral valve replacement (TAVR and TMVR) has emerged as an alternative to redo surgery. Despite the increasing experience in ViV procedures, the development of these techniques faces several specific challenges, mainly related to the unique anatomical and physiological characteristics presented in ViV-TAVR/TMVR. Subsequently, various approaches have been proposed to overcome ViV-related complications and pitfalls. A growing body of evidence is currently available concerning early- and long-term clinical outcomes of patients undergoing ViV-TAVR/TMVR. These data should be comprehensively evaluated by the Heart Team in the decision-making process involving patients with failing surgical bioprostheses. In this review, we aimed to delineate the technical challenges and risks associated with ViV-TAVR and ViV-TMVR, provide an updated overview of the main clinical results, and summarize the future perspectives of this evolving field.

Predictors of Procedural Success in Patients With Degenerated Surgical Valves Undergoing Transcatheter Aortic Valve-in-Valve Implantation

Background: Valve-in-Valve transcatheter aortic valve implantation (ViV-TAVI) is a growing alternative for redo-surgery in patients with degenerated surgical valves. To our knowledge, data are lacking on the determinants on ViV-TAVI procedural success in patients with degenerated surgical valves.

Methods: All consecutive patients undergoing ViV-TAVI for degenerated surgical valves at the Cleveland Clinic were analyzed. Data were extracted from our patient registry on baseline patient characteristics, echocardiographic parameters, and procedural details. To identify possible predictors of ViV-TAVI procedural success, we employed a multivariate logistic regression model.

Results: A total of 186 patients who underwent ViV-TAVI were analyzed, with procedural success (VARC-2 device success and absence of periprocedural MACCE) reported in 165 (88.7%) patients. Patients with successful ViV-TAVI were significantly younger and had more frequent utilization of the transfemoral access than those with failed procedure. Other baseline and procedural characteristics were comparable between both groups. In terms of echocardiographic parameters, the procedural success group had a significantly lower AV peak pressure gradient (62.1 ± 24.7 vs. 74.1 ± 34.6 mmHg; p = 0.04) and lower incidence of moderate-to-severe aortic regurgitation [AR] (30.4 vs. 55%; p = 0.04). However, no significant differences between both groups were noted in terms of AV mean pressure gradient and left ventricular measurements. In multivariate analysis, lower AV peak pressure gradient (OR = 0.97, 95% CI: 0.95–0.99) and absence of moderate-to-severe AR (OR = 0.65, 95% CI: 0.44–0.95) at baseline emerged as independent predictors of ViV-TAVI procedural success.

Conclusion: Valve-in-Valve TAVI for degenerated surgical valves is a feasible approach with high success rates, especially in those with lower AV peak pressure gradient and absence of moderate-to-severe AR. Studies with larger sample size and longer follow-up are required to further characterize the predictors of ViV-TAVI success and other clinical outcomes.

Valve-in-Surgical-Valve With SAPIEN 3 for Transcatheter Aortic Valve Replacement Based on Society of Thoracic Surgeons Predicted Risk of Mortality

[Figure: see text].

Transcatheter Aortic Valve Implantation for Failed Surgical Aortic Bioprostheses Using a Self-Expanding Device (from the Prospective VIVA Post Market Study)

Patients with symptomatic aortic stenosis are often treated with a surgical valve replacement. Surgical bioprosthetic valves degenerate over time and therefore may necessitate a redo surgery. This analysis reports the 2-year clinical outcomes of the Valve-in-Valve study, which evaluated transcatheter aortic valve implantation using the CoreValve and Evolut R devices in patients with degenerated surgical aortic bioprostheses at high risk for surgery. The prospective Valve-in-Valve study enrolled 202 eligible patients with failing surgical aortic bioprostheses due to stenosis, regurgitation, or a combination of both. The Evolut R bioprosthesis was used in 90.5% of valve-in-valve transcatheter aortic valve implantation cases. Two-year all-cause and cardiovascular mortality rates were 16.5% and 11.1%, respectively. Other clinical events included stroke (7.9%), disabling stroke (1.7%), and new pacemaker implantation (10.1%). The 2-year all-cause mortality rate was significantly higher in patients with discharge mean gradients ≥20 mmHg vs. those with lower mean gradients (21.0% vs 7.6%, p = 0.025). Discharge mean gradients ≥20 mm Hg were associated with smaller surgical bioprostheses (OR, 7.2 [95% CI 2.3 to 22.1]. In patients with failing surgical aortic bioprostheses, valve-in-valve treatment using a supra-annular self-expanding bioprosthesis provides significant functional improvements with acceptable rates of complications, especially if a postprocedural mean gradient of <20 mmHg can be achieved.

Expansion of TAVR into Low-Risk Patients and Who to Consider for SAVR

Transcatheter aortic valve replacement (TAVR) has revolutionized the treatment of severe aortic stenosis (AS) over the last decade. The results of the Placement of Aortic Transcatheter Valves (PARTNER) 3 and Evolut Low Risk trials demonstrated the safety and efficacy of TAVR in low-surgical-risk patients and led to the approval of TAVR for use across the risk spectrum. Heart teams around the world will now be faced with evaluating a deluge of younger, healthier patients with severe AS. Prior to the PARTNER 3 and Evolut Low Risk studies, this heterogenous patient population would have undergone surgical aortic valve replacement (SAVR). It is unlikely that TAVR will completely supplant SAVR for the treatment of severe AS in patients with a low surgical risk, as SAVR has excellent short- and long-term outcomes and years of durability data. In this review, we outline the critical role that SAVR will continue to play in the treatment of severe AS in the post-PARTNER 3/Evolut Low Risk era.

In-Vitro Assessment of the Effects of Transcatheter Aortic Valve Leaflet Design on Neo-Sinus Geometry and Flow

Transcatheter aortic valve (TAV) leaflet thrombosis is a clinical risk with potentially fatal consequences. Studies have identified neo-sinus flow stasis as a cause of leaflet thrombosis. Flow stasis is influenced by the TAV leaflets, which affect the local fluid dynamics in the aortic sinus and neo-sinus. This study evaluated the effects of TAV leaflet features on the neo-sinus flow as a measure of leaflet thrombosis risk. Five TAVs of varied leaflet length and insertion height were tested in a simulator. Hydrodynamics and leaflet kinematics through en-phase imaging were quantified. Velocity fields were assessed using high-speed particle image velocimetry. Regions of flow stasis and particle residence times (PRTs) were quantified. TAVs with shorter leaflet length exhibited larger orifice areas and lower transvalvular pressure gradients. Shorter leaflet length and increased leaflet insertion TAVs additionally exhibited lower neo-sinus PRTs (0.44 ± 0.21 vs 2.83 ± 0.48 cycles, p < 0.05) and higher neo-sinus peak velocities (0.15 ± 0.009 vs 0.07 ± 0.005 m/s, p < 0.05) than TAVs with longer leaflet length and lower leaflet insertion. The average neo-sinus volume positively correlated with PRT(r = 0.810, p < 0.001), and extent of flow stasis (r = 0.682, p < 0.05). These results suggest that a small neo-sinus volume may reduce flow stagnation and particle residence, potentially reducing the risk of leaflet thrombosis. We propose that leaflet design features might be proactively controlled in the design of future transcatheter aortic valves.

Long-term outcomes after transcatheter aortic valve implantation in failed bioprosthetic valves

Aims

Due to bioprosthetic valve degeneration, aortic valve-in-valve (ViV) procedures are increasingly performed. There are no data on long-term outcomes after aortic ViV. Our aim was to perform a large-scale assessment of long-term survival and reintervention after aortic ViV.

Methods and results

A total of 1006 aortic ViV procedures performed more than 5 years ago [mean age 77.7 ± 9.7 years; 58.8% male; median STS-PROM score 7.3% (4.2–12.0)] were included in the analysis. Patients were treated with Medtronic self-expandable valves (CoreValve/Evolut, Medtronic Inc., Minneapolis, MN, USA) (n = 523, 52.0%), Edwards balloon-expandable valves (EBEV, SAPIEN/SAPIEN XT/SAPIEN 3, Edwards Lifesciences, Irvine, CA, USA) (n = 435, 43.2%), and other devices (n = 48, 4.8%). Survival was lower at 8 years in patients with small-failed bioprostheses [internal diameter (ID) ≤ 20 mm] compared with those with large-failed bioprostheses (ID &gt; 20 mm) (33.2% vs. 40.5%, P = 0.01). Independent correlates for mortality included smaller-failed bioprosthetic valves [hazard ratio (HR) 1.07 (95% confidence interval (CI) 1.02–1.13)], age [HR 1.21 (95% CI 1.01–1.45)], and non-transfemoral access [HR 1.43 (95% CI 1.11–1.84)]. There were 40 reinterventions after ViV. Independent correlates for all-cause reintervention included pre-existing severe prosthesis–patient mismatch [subhazard ratio (SHR) 4.34 (95% CI 1.31–14.39)], device malposition [SHR 3.75 (95% CI 1.36–10.35)], EBEV [SHR 3.34 (95% CI 1.26–8.85)], and age [SHR 0.59 (95% CI 0.44–0.78)].

Conclusions

The size of the original failed valve may influence long-term mortality, and the type of the transcatheter valve may influence the need for reintervention after aortic ViV.

Meta-analysis Comparing Valve-In-Valve Transcatheter Aortic Valve Implantation With Self-Expanding Versus Balloon-Expandable Valves

Valve-in-valve (ViV) transcatheter aortic valve implantation (TAVI) is an alternative to redo-surgery in patients with failed surgical bioprostheses. It remains unclear whether outcomes vary when using either self-expanding (SE) or balloon-expandable (BE) valves. The aim of this study was to compare outcomes between SE and BE transcatheter heart valves when used for ViV TAVI. A systematic review of PubMed, MEDLINE, and EMBASE was performed identifying studies reporting outcomes following ViV TAVI. Event rates were pooled for meta-analysis using a random-effects model. The primary outcome was all-cause mortality at 12 months. Secondary outcomes included 30-day and 3-year mortality in addition to standard safety outcomes after the procedure as per the Valve Academic Research Consortium criteria. Nineteen studies reporting outcomes for 1,772 patients were included: 924 in the SE group and 848 patients in the BE group. There was no significant difference in all-cause mortality at 12 months (SE 10.3% vs BE 12.6%, p = 0.165, I² = 0%), or 3 years (SE 21.2% vs BE 31.2%, p = 0.407, I² = 63.79). SE valves had lower transvalvular gradients after procedure and acute kidney injury, but higher rates of pacemaker insertion, moderate or severe paravalvular regurgitation and need for ≥2 valves (all p < 0.05). There were no differences in stroke, coronary obstruction, bleeding, or vascular complications. Despite significant differences in key procedural outcomes between SE and BE valves when used for ViV TAVI, we found no difference in 12-month mortality. Tailored device selection may further reduce the risk of adverse procedural outcomes, particularly over the longer term.

Transcatheter Aortic Valve Implantation Current Indications and Future Directions

Degenerative heart valve disease is associated with significant morbidity and mortality and healthcare expenditures. Transcatheter heart valve repair and replacement has introduced a fundamental change in the therapeutic management and transcatheter aortic valve replacement (TAVR) has gained substantial popularity. Favorable results from randomized trials and large real world registries lead to TAVR being considered a standard procedure with high rates of procedural success and low rates of peri-procedural complications. This article aims to review the past evolution, summarize the available evidence, discuss current indications and limitations and venture a glimpse into the future of percutaneous interventions for aortic valve disease.