Stentless Aortic Valve Reoperations: A Surgical Challenge

Prosthetic Heart Valves: More than Half a Century of Innovation-An Overview

Since Dr. Charles Hufnagel introduced the first ball-in-cage valve prosthesis in 1952 to treat a patient with aortic regurgitation, the field of valvular heart disease has undergone remarkable evolution in both prosthetic valve development and patient management. Over the past 73 years, a wide range of valvular prostheses have been developed, each offering distinct advantages in terms of durability, thrombogenicity, and hemodynamics. This review aims to provide a detailed discussion of commonly known and used valvular heart prostheses, along with a review of newer endovascular prostheses. As ongoing research and innovation continue to shape the field, we can expect further improvements in hemodynamics, clinical outcomes, cost, ease of operation, and patient quality of life.

Short- and mid-term outcomes after redo surgical valve replacement

BACKGROUND

While previous studies have indicated comparable outcomes for redo surgical valve replacement (SVR) and primary SVR, there is limited information regarding the long-term follow-up of these patients. Providing prognostic data on redo SVR is crucial for enhancing decision-making and medical care, as well as for identifying low-risk subsets of patients eligible for redo SVR. This study aimed to evaluate the short- and mid-term outcomes of patients who underwent their first and second redo SVR of a previously replaced valve.

METHODS

We included 118 consecutive patients with a history of first or second redo SVR. The participants had a mean age of 57.5 ± 14.4 years, with 71 (60%) being female. The median follow-up period was 69 months. Clinical, intraoperative, and laboratory data were analyzed to assess all-cause mortality, major adverse events (MAE), and a composite of prosthetic valve thrombosis, embolic events, and major hemorrhage (TEH), along with their predictors. Bayesian model averaging was used for statistical analysis.

RESULTS

The 30-day mortality rate was 11 patients (9.3%). Chronic kidney disease was identified as an independent predictor of 30-day mortality. The overall survival rates at one and five years were 86% (95% CI 80% to 93%) and 76% (95% CI 68% to 85%), respectively. Dyslipidemia, a history of major bleeding, chronic kidney disease, stroke, and transvalvular leakage in biological prostheses were all associated with all-cause mortality as independent predictors. The TEH-free survival rates at one and five years were 91% (95% CI 86% to 97%) and 79% (95% CI 71% to 88%), respectively. Diabetes, sex, a history of percutaneous coronary intervention, and baseline functional capacity were identified as independent predictors for the occurrence of TEH. The MAE-free survival rates at one and five years were 82% (95% CI 73% to 92%) and 61% (95% CI 49% to 75%), respectively. Hypertension and baseline functional class were independent predictors of MAE occurrence. The type and anatomical position of the valve were not predictors of mortality, THE, and MAE.

CONCLUSIONS

Our study demonstrated acceptable short- and mid-term outcomes for redo SVR, especially in patients without significant risk factors. Several potential predictors of adverse outcomes were identified.

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.

Interventional versus Surgical Treatment of Degenerated Freestyle Prosthesis

BACKGROUND

 Bioprosthetic stentless aortic valves may degenerate over time and will require replacement. This study aimed to evaluate early- and mid-term outcomes after isolated surgical redo aortic valve replacement (redo-SAVR) and transcatheter valve-in-valve implantation (TAVI-VIV) for degenerated stentless Freestyle bioprostheses.

METHODS

 We reviewed records of 56 patients at a single center. Overall, 37 patients (66.1%) received TAVI-VIV and 19 (33.9%) received redo-SAVR.

RESULTS

 Thirty-day survival was similar in both groups (100%). One-year survival was comparable between groups (97.3% in TAVI-VIV and 100% in redo-SAVR, p = 1.0). The difference in mid-term survival after adjusting for age and EuroScore II was not significant (p = 0.41). The incidence of pacemaker implantation after TAVI-VIV was higher than after redo-SAVR (19.4% vs. 0%, p = 0.08).

CONCLUSION

 The 30-day and 1-year survival rates after both procedures were outstanding, irrespective of baseline characteristics. Isolated redo-SAVR should be favored in young patients, as the pacemaker implantation rate is lower. TAVI-VIV for degenerated Freestyle prosthesis can be a method of choice in elderly patients and those with high operative risk.

Intermediate-term Outcomes Following a Case Series of Reoperations for Medtronic Freestyle Stentless Aortic Valves

Background

Data are limited on long-term outcomes in patients who have undergone a reoperation following failure of a stentless aortic valve.

Methods

Between 2006 and 2016, a retrospective analysis was performed on 24 patients who underwent open aortic valve replacement surgery for a failed stentless aortic valve prosthesis at Health Sciences North, Sudbury, Ontario, Canada. The primary outcome was a low mortality rate from cardiac-related deaths after 5 years.

Results

All patients underwent insertion of a Medtronic Freestyle bioprosthesis (Minneapolis, MN) implanted using the modified subcoronary technique for their initial operation. The interval from the first operation to the stentless redo surgery ranged from 6 to 13 years. Aortic valve reoperation was performed for structural valve deterioration in 96% (n = 23) of the cases. Reoperations involved a removal of the stented valve leaflets and standard aortic valve replacement within the stentless casing in 20% (n = 5) of the cases, with the remaining cases requiring complete removal of the stentless prosthesis and aortic valve replacement. In those in whom a complete removal of the stentless valve was possible (n = 19), no disruption of the native aortic root occurred, with a 0% rate of conversion to a Bentall procedure. No intraoperative mortality occurred. The 30-day and 10-year operative mortality rates were 4% and 16%, respectively.

Conclusions

Redo surgery for failing stentless valves can be done with relatively low risk and with acceptable long-term outcomes without resorting to root-replacement techniques.

Transcatheter aortic valve-in-valve implantation within stentless landing zones: Procedural insights from a single-center experience

BACKGROUND

Valve-in-valve (VIV) transcatheter aortic valve implantation (TAVI) is a less invasive therapeutic option compared with redo surgical valve replacement for high-risk patients. Relative to procedures within stented surgical valves, VIV-TAVI within stentless valves is associated with a higher complication rate due to challenging underlying anatomy and absence of fluoroscopic landmarks.

AIMS

We share a single-center experience with VIV-TAVI in stentless valves, discussing our procedural insights and associated outcomes.

METHODS

Our institutional database was queried, and 25 patients who had undergone VIV-TAVI within a stentless bioprosthesis, homograft, or valve-sparing aortic root replacement between 2013 and 2022 were found. Outcome endpoints were based on the Valve Academic Research Consortium-3 criteria.

RESULTS

The mean age of the cohort was 69.5 ± 13.6 years. VIV implantation was performed within a homograft in 11 patients, a stentless bioprothesis in 10 patients, and a valve-sparing aortic root replacement in 4 patients. Nineteen (76%) balloon-expandable valves, 5 (20%) self-expanding valves, and one mechanically-expandable (4%) valve were implanted with 100% procedural success, with no instances of significant paravalvular leak, coronary occlusion, or device embolization. There was one (4%) in-hospitality mortality after an emergency procedure; one (4%) patient experienced a transient ischemic attack; and two (8%) patients required permanent pacemaker implantation. The median length of hospital stay was 2 days. After a median follow-up time of 16.5 months, valve function was acceptable in all patients with available data.

CONCLUSION

VIV-TAVI within stentless valves can be safely performed with methodical procedural technique and can provide clinical benefit in patients at high reoperation risk.

Long-term outcomes of aortic root operations in the United States among Medicare beneficiaries

OBJECTIVE

The best method of aortic root repair in older patients remains unknown given a lack of comparative effectiveness of long-term outcomes data. The objective of this study was to compare long-term outcomes of different surgical approaches for aortic root repair in Medicare patients using The Society of Thoracic Surgeons Adult Cardiac Surgery Database-Centers for Medicare & Medicaid Services-linked data.

METHODS

A retrospective cohort study was performed by querying the Society of Thoracic Surgeons Adult Cardiac Surgery Database for patients aged 65 years or more who underwent elective aortic root repair with or without aortic valve replacement. Primary long-term end points were mortality, any stroke, and aortic valve reintervention. Short-term outcomes and long-term survival were compared among each root repair strategy. Additional risk factors for mortality after aortic root repair were assessed with a multivariable Cox proportional hazards model.

RESULTS

A total of 4173 patients aged 65 years or more underwent elective aortic root repair. Patients were stratified by operative strategy: mechanical Bentall, stented bioprosthetic Bentall, stentless bioprosthetic Bentall, or valve-sparing root replacement. Mean follow-up was 5.0 (±4.6) years. Relative to mechanical Bentall, stented bioprosthetic Bentall (adjusted hazard ratio, 0.80; confidence interval, 0.66-0.97) and stentless bioprosthetic Bentall (adjusted hazard ratio, 0.70; confidence interval, 0.59-0.84) were associated with better long-term survival. In addition, stentless bioprosthetic Bentall (adjusted hazard ratio, 0.64; confidence interval, 0.47-0.80) and valve-sparing root replacement (adjusted hazard ratio, 0.51; confidence interval, 0.29-0.90) were associated with lower long-term risk of stroke. Aortic valve reintervention risk was 2-fold higher after valve-sparing root replacement compared with other operative strategies.

CONCLUSIONS

In the Medicare population, there was poorer late survival and greater late stroke risk for patients undergoing mechanical Bentall and a higher rate of reintervention for valve-sparing root replacement. Bioprosthetic Bentall may be the procedure of choice in older patients undergoing aortic root repair, particularly in the era of transcatheter aortic valve replacement.

Early and mid-term outcomes after aortic valve intervention in patients with previous stentless or stented bioprostheses

BACKGROUND

Limited data are available concerning comparative outcomes of redo aortic valve interventions, including surgery after aortic valve replacement (AVR) with either stented or stentless bioprostheses. We investigated the comparative outcomes of redo aortic valve interventions, including surgery after AVR with either stented or stentless bioprostheses.

METHODS

The cohort consisted of 112 patients who underwent aortic valve intervention for infective endocarditis or structural valve deterioration between 2001 and 2020. One hundred patients received a stented valve (stented group) and 12 patients received a stentless valve (stentless group) during the initial surgery. Early and late outcomes were evaluated.

RESULTS

The mean [IQR] ages during the current interventions were 66 [54, 77] years in the stented group and 74 [67, 79] years in the stentless group (P = 0.13). In the stented group, aortic valve interventions included redo AVRs with stented valves (n = 54), mechanical valves (n = 26), stentless valves (n = 16), and transcatheter aortic valve implantations (n = 4). In the stentless group, redo AVRs were performed with stented valves (n = 4), mechanical valves (n = 2), stentless valves (n = 1), and transcatheter valve implantations (n = 5). Hospital mortality was observed in 2 (2%) patients in the stented group and 1 (8%) patients in the stentless group (P = 0.29). The 5-year survival was 80.8% [66.8, 88.5] in the stented group and 91.7% [53.9, 98.8] in stentless group. Statistically significant differences in thromboembolisms were observed between the groups.

CONCLUSIONS

No significant differences in early and mid-term outcomes (except thromboembolism) after aortic valve interventions were detected between patients with stented and stentless AVRs.

Transcatheter valve-in-valve implantation for degenerated stentless aortic bioroots

Background

Open surgical repair of a failed valve-sparing aortic root replacement (VSARR) or stentless bioroot aortic root replacement (bio-ARR) entails significant operative risks. Whether valve-in-valve transcatheter aortic valve replacement (ViV-TAVR) is feasible in patients with a previous VSARR or stentless bio-ARR remains unclear, given lingering concerns about the ill-defined aortic annulus in these patients and the potential for coronary obstruction. We present our experience with patients who had a previous VSARR or stentless bio-ARR and underwent ViV-TAVR to repair a degenerated aortic valve with combined valvular disease, aortic insufficiency and aortic stenosis.

Methods

In this retrospective data review, we identified and analyzed consecutive patients with a previous VSARR or stentless bio-ARR who underwent ViV-TAVR between December 1, 2014 and August 31, 2019.

Results

ViV-TAVR was performed in twelve high-risk patients with previous VSARR or bio-ARR during the study period. Of these, seven received Medtronic Freestyle porcine stentless bioprosthetic aortic roots, three received homograft aortic roots, one underwent a Ross procedure and one underwent VSARR. ViV-TAVR restored satisfactory valve function in all patients, and technical success was 100%. No patient had more than mild regurgitation after implantation. No thirty-day mortality was seen. One patient had major bleeding after transapical access, one patient had a transient ischemic stroke, and one patient needed permanent pacemaker implantation. At a median last follow-up of 21.5 months (interquartile range, 9.0-69.0 months), all patients remained alive and had satisfactory valve function.

Conclusions

In this study, ViV-TAVR was a clinically effective option for treating patients with a failed stentless bio-ARR or previous VSARR. Short-term and intermediate-term results after these procedures were favorable. These findings may have important implications for treating high-risk patients with structural aortic root deterioration and call for better transcatheter heart valves that are suitable for treating aortic insufficiency.

Propensity matched long-term analysis of mechanical versus stentless aortic valve replacement in the younger patient

OBJECTIVES

The choice of prosthesis for aortic valve replacement (AVR) in younger patients remains controversial. Stentless AVR was introduced 3 decades ago, with the aim of better haemodynamics and durability than stented xenografts. The objective of this analysis was to compare the long-term outcomes to mechanical prostheses in younger patients (age ≤60 years).

METHODS

All adult patients who underwent AVR due to aortic valve stenosis and/or insufficiency between 1993 and 2002 were identified. After the exclusion of patients with congenital heart defects, aortic dissections and Ross-procedures, 158 patients with stentless valves and 226 patients with bi-leaflet mechanical valves were finally included in this analysis. Sixty-six patient pairs could be included in a propensity matched analysis. Mortality and morbidity including stroke, bleeding, endocarditis and reoperation were analysed.

RESULTS

Group baseline characteristics and operative data did not differ significantly after propensity matching. Hospital mortality was 0.0% in the stentless and 1.5% in the mechanical group. Total patient years/median follow-up was 2029.1/15.4 years (completeness: 100.0%, range: 0-25 years). After 20 years, actuarial survival was 47.0 ± 6.4% in the stentless and 53.3 ± 6.6% in mechanical group (P = 0.69). Bleeding, endocarditis and stroke occurred rarely and did not differ significantly between groups. After 20 years, actuarial overall freedom-from-reoperation was 45.1 ± 8.2% in the stentless group and 90.4 ± 4.1% in the mechanical group (P < 0.001). Hospital mortality while reoperation was 7.4% in the stentless group and 0% in the mechanical group (P = 1.0).

CONCLUSIONS

Long-term morbidity and mortality of stentless and mechanical aortic valves were statistically not different besides a significantly higher reoperation rate after stentless AVR combined with a probably higher risk of in-hospital mortality. Thus, mechanical AVR should remain the procedure of choice in younger patients.

Redo-aortic valve replacement in prior stentless prosthetic aortic valves: Transcatheter versus surgical approach

OBJECTIVES

The objective was to compare outcomes of redo-aortic valve replacement (AVR) via surgical or transcatheter approach in prior surgical AVR with large percentage of prior stentless surgical AVR.

BACKGROUND

With the introduction of transcatheter aortic valve replacement (TAVR), patients with increased surgical risks now have an alternative to redo surgical AVR (SAVR), known as valve-in-valve (ViV) TAVR. Stentless prosthetic aortic valves present a more challenging implantation for ViV-TAVR given the lack of structural frame.

METHODS

We performed a retrospective study of 173 subjects who have undergone SAVR (N = 100) or ViV-TAVR (N = 73) in patients with prior surgical AVR at Wake Forest Baptist Medical Center from 2009 to 2019. Our study received the proper ethical oversight.

RESULTS

The average ages in redo-SAVR and ViV-TAVR groups were 58.03 ± 13.86 and 66.57 ± 13.44 years, respectively (p < 0.0001). The redo-SAVR had significantly lower STS (2.78 ± 2.09 and 4.68 ± 5.51, p < 0.01) and Euroscores (4.32 ± 2.98 and 7.51 ± 8.24, p < 0.05). The redo-SAVR group had higher percentage requiring mechanical support (8% vs. 0%, p < 0.05) and vasopressors (53% vs. 0%, p < 0.0001), longer length of stay (13.65 ± 11.23 vs. 5.68 ± 7.64 days, p < 0.0001), and inpatient mortality (16% vs. 2.78%, p < 0.005). At 30-day follow-up, redo-SAVR group had higher rates of acute kidney injury (10% vs. 0%, p < 0.01), however ViV-TAVR group had more new left bundle branch blocks (6.85% vs. 0%, p < 0.05). No significant differences regarding re-hospitalization rates, stroke, or death up to 1-year.

CONCLUSION

Although the ViV-TAVR group had higher risk patients, there were significantly fewer procedural complications, shorter length of stay, and similar mortality outcomes up to 1-year follow-up.

Fifty years of the pericardial valve: Long-term results in the aortic position

It is now 50 years since the development of the first pericardial valve in 1971. In this time significant progress has been made in refining valve design aimed at improving the longevity of the prostheses. This article reviews the current literature regarding the longevity of pericardial heart valves in the aortic position. Side by side comparisons of freedom from structural valve degeneration are made for the valves most commonly used in clinical practice today, including stented, stentless, and sutureless valves. Strategies to reduce structural valve degeneration are also discussed including methods of tissue fixation and anti-calcification, ways to minimise mechanical stress on the valve, and the role of patient prosthesis mismatch.

Valve-in-valve transcatheter aortic valve replacement versus redo surgical aortic valve replacement: A systematic review and meta-analysis

BACKGROUND/AIM

With the growing contemporary use of bioprosthetic valves, whose limited long-term durability has been well-documented, an increase in the need for reintervention is expected. We perform a meta-analysis to compare the current standard of care, redo surgical aortic valve replacement (Redo SAVR) with the less invasive alternative, valve-in-valve transcatheter aortic valve replacement (ViV TAVR) for treating structural valve deterioration.

METHODS

After a comprehensive literature search, studies comparing ViV TAVR to Redo SAVR were pooled to perform a pairwise meta-analysis using the random-effects model. Primary outcomes were 30-day and follow-up mortality.

RESULTS

A total of nine studies including 9127 patients were included. ViV TAVR patients were significantly older (mean difference [MD], 5.82; p = .0002) and more frequently had hypercholesterolemia (59.7 vs. 60.0%; p = .0006), coronary artery disease (16.1 vs. 16.1%; p = .04), periphery artery disease (15.4 vs. 5.7%; p = .004), chronic obstructive pulmonary disease (29.3 vs. 26.2%; p = .04), renal failure (30.2 vs. 24.0%; p = .009), and >1 previous cardiac surgery (23.6 vs. 15.9%; p = .004). Despite this, ViV TAVR was associated with decreased 30-day mortality (OR, 0.56; p < .0001). Conversely, Redo SAVR had lower 30-day paravalvular leak (OR, 6.82; p = .04), severe patient-prosthesis mismatch (OR, 3.77; p < .0001), and postoperative aortic valve gradients (MD, 5.37; p < .0001). There was no difference in follow-up mortality (HR, 1.02; p = .86).

CONCLUSIONS

Despite having patients with an increased baseline risk, ViV TAVR was associated with lower 30-day mortality, while Redo SAVR had lower paravalvular leak, severe patient-prosthesis mismatch, and postoperative gradients. Although ViV TAVR remains a feasible treatment option in high-risk patients, randomized trials are necessary to elucidate its efficacy over Redo SAVR.

Transcatheter valve-in-valve implantation versus surgical redo aortic root replacement in patients with degenerated freestyle aortic bioprosthesis

BACKGROUND

Transcatheter aortic valve-in-valve implantation (ViV TAVI) represents a new treatment option for patients with degenerated aortic bioprosthesis. Comparative data to redo surgical aortic valve replacement (redo SAVR) are limited.

OBJECTIVE

We investigated feasibility and outcome of ViV TAVI versus redo SAVR in patients with symptomatic degenerated Medtronic Freestyle aortic bioprosthesis (FSB).

METHODS

Between January 2002 and February 2020, 25 patients with failed FSB underwent ViV TAVI and 10 patients with failed FSB underwent redo SAVR. Endpoints were defined according to the Valve Academic Research Consortium-2 (VARC-2) criteria.

RESULTS

Age and logistic EuroSCORE II were higher in patients with ViV TAVI (75.4 ± 1.7 vs. 62.9 ± 5.1 years, p = .019; 11.5 ± 1.6 vs. 5.6 ± 5.6%, p = .007). Valve implantation was successful in all cases. Mean transvalvular pressure gradients were significantly lower in patients with redo SAVR than ViV TAVI (7.6 ± 1.0 vs. 10.3 ± 0.8 mmHg, p = .037). Aortic valve regurgitation was absent in 91% and 100% of patients with ViV TAVI and redo SAVR, respectively. Thirty-day mortality rates were 12% in the ViV TAVI cohort versus 0% in the redo SAVR cohort (p = .542). Within the first year after hospital discharge, one patient after ViV TAVI had redo surgical intervention.

CONCLUSIONS

ViV TAVI and redo SAVR lead to excellent functional results in patients with degenerated FSB. Post-procedural early complications must be considered particularly in patients with ViV TAVI because of higher clinical risk profiles.

Successful Reoperation in 3 Cases of Failed Sorin Freedom Stentless Aortic Valve Using the LivaNova Perceval Sutureless Prosthesis

Reoperations for deteriorated stentless bioprostheses are quite challenging procedures. Calcification of the aortic annulus and of the subcoronary root makes often impossible the removal of the failed valve, living a complex Bentall operation or a high-risk transcatheter aortic valve implantation valve-in-valve procedure as the only options, particularly in cases of small-size prostheses. The Perceval sutureless prosthesis (LivaNova PLC, London, UK) can be a valid alternative for failed stentless valve replacement. We report our experience with 3 complex cases of degenerated Sorin Pericarbon Freedom prosthesis treated successfully by means of Perceval sutureless implantation and demonstrating the reproducibility and the safety of this surgical approach.

Long-term clinical outcomes of the Toronto stentless porcine valve: 15-year results from dual centers

BACKGROUND AND AIM OF THE STUDY

The purpose of this study is to examine the long-term durability of the Toronto stentless porcine valve (SPV) in the aortic position (St Jude Medical, Minneapolis, MN).

METHODS

We assessed the long-term clinical outcomes of 515 patients with aortic valve replacement (AVR) with the Toronto SPV from 1987 to 2001 at two centers, excluding early (<30 days) death. Median follow-up was 11.5 years (maximum 19.0 years).

RESULTS

Average age was 64.2 ± 10.8 years, and females were 34% (173/515). The incidence of prosthesis-patient mismatch was low, 10.9%. Overall survival was 90.7 ± 1.3%, 75.4 ± 2.0%, and 56.8 ± 3.2% at 5, 10, and 15 years, respectively after surgery. Over the follow-up duration, 116 patients (23%) underwent repeated AVR: 90 for structural valve deterioration (SVD), 12 for endocarditis, 10 nonstructural valve dysfunction (10 aortic regurgitation due to aorta dilatation), and four for other reasons. The cumulative incidence of repeated AVR with death as a competing risk was 1.4% (95% confidence interval [CI], 0.6-2.7), 11.1% (95% CI, 8.4-14.2), and 34.4% (95% CI, 28.8-40.2) at 5, 10, and 15 years, respectively. Reoperative mortality was 5.2% (6/116). In SVD, the regurgitation type was dominant (82%).

CONCLUSIONS

The Toronto SPV is associated with excellent survival and durability during the first decade of follow-up. However, regurgitation type of SVD increases from 10 years after operation with acceptable reoperative mortality. These findings may assist with prosthesis selection and reintervention strategy for failing stentless bioprosthesis.

Reinterventions after freestyle stentless aortic valve replacement: an assessment of procedural risks

OBJECTIVES

Repeat aortic valve interventions after previous stentless aortic valve replacement (AVR) are considered technically challenging with an increased perioperative risk, especially after full-root replacement. We analysed our experience with reinterventions after stentless AVR.

METHODS

A total of 75 patients with previous AVR using a Freestyle stentless bioprosthesis (31 subcoronary, 15 root-inclusion and 29 full-root replacement) underwent reintervention in our centre from 1993 until December 2018. Periprocedural data were retrospectively collected from the department database and follow-up data were prospectively collected.

RESULTS

Median age was 62 years (interquartile range 47-72 years). Indications for reintervention were structural valve deterioration (SVD) in 47, non-SVD in 13 and endocarditis in 15 patients. Urgent surgery was required in 24 (32%) patients. Reinterventions were surgical AVR in 16 (21%), root replacement in 51 (68%) and transcatheter AVR in 8 (11%) patients. Early mortality was 9.3% (n = 7), but decreased to zero in the past decade in 28 patients undergoing elective reoperation. Per indication, early mortality was 9% for SVD, 8% for non-SVD and 13% for endocarditis. Aortic root replacement had the lowest early mortality rate (6%), followed by surgical AVR (13%) and transcatheter AVR (25%, 2 patients with coronary artery obstruction). Pacemaker implantation rate was 7%. Overall survival rate at 10 years was 69% (95% confidence interval 53-81%).

CONCLUSIONS

Repeat aortic valve interventions after stentless AVR carry an increased, but acceptable, early mortality risk. Transcatheter valve-in-valve procedures after stentless AVR require careful consideration of prosthesis leaflet position to prevent obstruction of the coronary arteries.

Rapid-deployment aortic valve replacement after aortic root replacement: A safe alternative to redo root replacement

Reoperative aortic root replacement, following prior biologic or mechanical valved conduit aortic root prosthesis, presents a technical challenge. The rapid-deployment aortic valve prosthesis is an approved alternative to traditional bioprosthetic aortic valve replacement. We present three clinical cases in which rapid-deployment aortic valve prostheses were utilized in lieu of reoperative full aortic root replacement. All three patients recovered uneventfully. The rapid-deployment valve insertion in a prior surgical aortic root prosthesis is a safe option to avoid reoperative full aortic root replacement.

The Use of Biological Heart Valves

BACKGROUND

Biological heart-valve prostheses have undergone continuous devel- opment up to the present, and technological advances have been made in catheter- assisted valve systems (transcatheter aortic valve implantation, TAVI) and minimally invasive routes of application. These parallel trends have led to major changes in therapeutic strategies, widening the spectrum of patients who are candidates for biological aortic valve implantation.

METHODS

This review is based on pertinent publications retrieved by a systematic search in PubMed employing the search terms "conventional biological aortic pros- thesis," "rapid deployment prosthesis," and "transcatheter aortic valve implantation/ replacement."

RESULTS

Among biological heart-valve prostheses, a distinction is drawn between stented (conventional, rapid-deployment, and catheter-assisted) and non-stented types. The long-term durability of conventional, surgically implantable biological valve protheses is by far the best documented: the reported 5-year reoperation rates range from 13.4% to 36.6%, and the pacemaker implantation rate is ca. 4%. Rapid-deployment prostheses combine the advantages of conventional and ca- theter-assisted techniques and facilitate minimally invasive approaches. The TAVI method is currently recommended for high- and intermediate-risk patients, while conventional valve replacement remains the method of choice for those at low risk. Rapid-deployment and TAVI prostheses is associated with a higher pacemaker im- plantation rate than conventional prostheses: these rates are 8.5-15.3% for TAVI and 6.0-8.8% for rapid-deployment valves. The intermediate-term durability of catheter-assisted and rapid-deployment prostheses appears promising, but their long-term durability is still unclear.

CONCLUSION

The further development of biological heart-valve prostheses in the form of improved conventional, transcatheter, and rapid-deployment prostheses now enables individualized treatment. Before any such procedure is performed, the car- diac team must assess the patient's risk profile and the advantages and disadvan- tages of each type of prosthesis to determine which is best.

A comparison of valve-in-valve transcatheter aortic valve replacement in failed stentless versus stented surgical bioprosthetic aortic valves

Objectives

The objectives of this study were to compare short‐ and intermediate‐term clinical outcomes, procedural complications, TAVR prosthesis hemodynamics, and paravalvular leak (PVL) in stentless and stented groups.

Background

Valve‐in‐valve (ViV) transcatheter aortic valve replacement (TAVR) is an alternative to surgical redo for bioprosthetic valve failure. There have been limited data on ViV in stentless surgical valves.

Methods

We retrospectively analyzed 40 patients who underwent ViV TAVR in prior surgical bioprosthetic valves at Wake Forest Baptist Medical Center from October 2014 to September 2017. Eighty percent (32/40) ViV TAVRs were in stentless, while 20% (8/40) were in stented bioprosthetic valves.

Results

The primary mode of bioprosthetic valve failure for ViV implantation in the stentless group was aortic insufficiency (78%, 25/32), while in the stented group was aortic stenosis (75%, 6/8). The ViV procedure success was 96.9% (31/32) in stentless group and 100% in stented group (8/8). There were no significant differences in all‐cause mortality at 30 days between stentless and stented groups (6.9%, 2/31 versus 0%, 0/8, P = 0.33) and at 1 year (0%, 0/25 versus 0%, 0/5). In the stentless group, 34.4% (11/32) required a second valve compared to the stented group of 0% (0/8). There was a significant difference in the mean aortic gradient at 30‐day follow‐up (12.33 ± 6.33 mmHg and 22.63 ± 8.45 mmHg in stentless and stented groups, P < 0.05) and at 6‐month follow‐up (9.75 ± 5.07 mmHg and 24.00 ± 11.28 mmHg, P < 0.05), respectively.

Conclusions

ViV in the stentless bioprosthetic aortic valve has excellent procedural success and intermediate‐term results. Our study shows promising data that may support the application of TAVR in stentless surgical aortic valve. However, further and larger studies need to further validate our single center's experience.

Stented versus Stentless Aortic Valve Replacement in Patients with Small Aortic Root

Objective

The aim of the study was to compare hemodynamic and perioperative outcomes of stented against stentless aortic valve replacement in patients with small aortic root (21 mm or less).

Methods

A comprehensive search was undertaken among the four major databases (PubMed, Embase, Scopus, and Ovid) to identify all randomized and nonrandomized controlled trials comparing stentless to stented bioprosthetic valves in small aortic root patients. Odds ratios, weighted mean differences, or standardized mean differences and their 95% confidence intervals were analyzed.

Results

A total of seven studies with a total of 965 patients fulfilled the inclusion criteria. There was no significant difference in preoperative baselines including mean age between both groups ( P = 0.08), peak aortic valve gradient ( P = 0.06), and effective orifice area ( P = 0.28), whereas higher mean aortic valve gradient in the stented group ( P = 0.007). No difference in cardiopulmonary bypass time ( P = 0.74), aortic cross-clamp times ( P = 0.88), intensive care unit stay ( P = 0.13), and stroke rate ( P = 0.56) were noted. However, stented group of patients showed higher rate of patient prosthesis mismatch ( P = 0.0001) and longer total hospital stay ( P = 0.002). Postoperatively, stentless group showed lower peak and mean aortic valve gradient ( P = 0.003 and P = 0.008, respectively) with a better effective orifice area ( P < 0.00001) at 6 months of follow-up. Mortality rates while in-hospital and at 1 year were similar in both groups ( P = 0.94 and P = 0.86, respectively).

Conclusions

Stentless aortic valves offer superior short-term hemodynamic outcomes in patients with small aortic root when compared with stented aortic valves. Although both groups have similar perioperative complications rates, stentless valves bring about a shorter hospital stay. A further large multicenter randomized controlled trial should address the longer-term benefit of stentless aortic valve over stented valve.

Hemi-Cabrol Aortic Root Replacement in Complex Aortic Reconstructions

The Cabrol aortic root replacement with subsequent modifications remains an extremely useful technique within the armamentarium of the aortic surgeon. The technical considerations detailed here allow for the uncompromised creation of a hemi-Cabrol anastomosis in complex aortic reconstructions.

Morphometrical and biomechanical analyses of a stentless bioprosthetic valve: an implication to avoid potential primary tissue failure

OBJECTIVES

Stentless bioprosthetic valves provide hemodynamic advantages over stented valves as well as excellent durability. However, some primary tissue failures in bioprostheses have been reported. This study was conducted to evaluate the morphometrical and biomechanical properties of the stentless Medtronic Freestyle™ aortic root bioprosthesis, to identify any arising problem areas, and to speculate on a potential solution.

METHODS

The three-dimensional heterogeneity of the stentless bioprosthesis wall was investigated using computed tomography. The ascending aorta and the right, left, and non-coronary sinuses of Valsalva were resected and examined by an indentation test to evaluate their biomechanical properties.

RESULTS

The non-coronary sinus of Valsalva was significantly thinner than the right sinus of Valsalva (p < 0.01). Young's modulus, calculated as an indicator of elasticity, was significantly greater at the non-coronary sinus of Valsalva (430.7 ± 374.2 kPa) than at either the left (190.6 ± 70.6 kPa, p < 0.01) or right sinuses of Valsalva (240.0 ± 56.5 kPa, p < 0.05).

CONCLUSIONS

Based on the morphometrical and biomechanical analyses of the stentless bioprosthesis, we demonstrated that there are differences in wall thickness and elasticity between each sinus of Valsalva. These differences suggest that the non-coronary sinus of Valsalva is the most vulnerable and at greater risk of tissue failure. The exclusion of the non-coronary sinus of Valsalva may be beneficial to mitigate the long-term risks of tissue failure in the stentless bioprosthesis.

Meta-Analysis of Transcatheter Valve-in-Valve Implantation Versus Redo Aortic Valve Surgery for Bioprosthetic Aortic Valve Dysfunction

Transcatheter valve-in-valve implantation (ViV-TAVI) has evolved as an alternative to redo surgical valve replacement (redo-SAVR) for high-risk patients with aortic bioprosthetic valve (BPV) dysfunction. The differences in procedural success and outcomes in a large number of patients who underwent ViV-TAVI compared with redo-SAVR for aortic BPV dysfunction are not known. We conducted a meta-analysis of the previously reported studies to determine outcomes after ViV-TAVI and redo-SAVR. PubMed, MEDLINE, and Google Scholar databases were searched for studies that reported comparative outcomes of patients who underwent either ViV-TAVI or redo-SAVR. Four observational studies met the inclusion criteria, with a total of 489 patients, 227 of whom underwent ViV-TAVI and 262 underwent redo-SAVR. Thirty-day mortality was similar in 2 groups (5% vs 4%; odds ratio [OR] = 1.08, 95% confidence interval [CI] = 0.44 to 2.62) despite the higher operative risk in the ViV-TAVI cohort as evidenced by significantly higher EuroSCORE I or II. There were similar rates of stroke (2% vs 2%; OR = 1.00, 95% CI = 0.28 to 3.59), myocardial infarction (2% vs 1%; OR = 1.08, 95% CI = 0.27 to 4.33), and acute kidney injury requiring dialysis (7% vs 10%; OR = 0.80, 95% CI = 0.36 to 0.1.77) between 2 groups but a lower rate of permanent pacemaker implantation in the ViV-TAVI group (9% vs 15%; OR = 0.44, 95% CI = 0.24 to 0.81). This meta-analysis of nonrandomized studies with modest number of patients suggested that ViV-TAVI had similar 30-day survival compared with redo-SAVR for aortic BPV dysfunction.

A standardized approach to treat complex aortic valve endocarditis: a case series

Background

Surgical treatment of complicated aortic valve endocarditis often is challenging, even for experienced surgeons. We aim at demonstrating a standardized surgical approach by stentless bioprostheses for the treatment of aortic valve endocarditis complicated by paravalvular abscess formation.

Methods

Sixteen patients presenting with aortic valve endocarditis (4 native and 12 prosthetic valves) and paravalvular abscess formation at various localizations and to different extents were treated by a standardized approach using stentless bioprostheses. The procedure consisted of thorough debridement, root replacement with reimplantation of the coronary arteries and correction of accompanying pathologies (aortoventricular and aortomitral dehiscence, septum derangements, Gerbode defect, total atrioventricular conduction block, mitral and tricuspid valve involvement).

Results

All highly complex patients included (14 males and 2 females; median age 63 years [range 31–77]) could be successfully treated with stentless bioprostheses as aortic root replacement. Radical surgical debridement of infected tissue with anatomical recontruction was feasible. Although predicted operative mortality was high (median logarithmic EuroSCORE I of 40.7 [range 12.8–68.3]), in-hospital and 30-day mortality rates were favorable (18.8 and 12.5% respectively).

Conclusions

Repair of active aortic valve endocarditis complicated by paravalvular abscess formation and destruction of the left ventricular outflow tract with stentless bioprosthesis is a valuable option for both native and prosthetic valves. It presents a standardized approach with a high success rate for complete debridement, is readily available, and yields comparable clinical outcomes to the historical gold standard, repair by homografts. Additionally, use of one type of prosthesis reduces logistical issues and purchasing costs.

Aortic Valve Reoperation After Stentless Bioprosthesis: Short- and Long-Term Outcomes

BACKGROUND

Limited data are available regarding outcomes for stentless aortic valve reoperation. The reported reoperative mortality has been unacceptably high.

METHODS

Between 1997 and 2017, a retrospective analysis was performed on 143 patients who underwent open aortic valve reoperations for failed stentless aortic valve bioprostheses. We evaluated both short-term and long-term outcomes on this cohort of patients.

RESULTS

Bicuspid aortic valve was present in 107 of 143 patients (75%) at the time of the initial Freestyle (Medtronic, Minneapolis, MN) procedure, and 120 of 143 patients (84%) underwent a modified inclusion aortic root replacement procedure. The interval from first operation to reoperation was 9 years (range, 5.4 to 11.8), which was significantly shorter for patients with infectious endocarditis (4.1 years; range, 1.8 to 7.1) compared with patients with structural valvular deterioration (10.4 years; range, 8.1 to 12.4, p < 0.001). The median age at the time of reoperation was 59 years (range, 50 to 67). Aortic valve reoperation was performed for structural valve deterioration in 68% cases compared with 32% for infectious prosthetic valve endocarditis. Concomitant surgery included coronary artery bypass (13%), mitral valve surgery (4%), and ascending aorta and arch replacement (42%). The 30-day and inhospital mortality was 1% and 2%, respectively. The composite outcome including myocardial infarction, stroke, new-onset renal failure on hemodialysis, and operative mortality was 4%. The 5-year and 10-year Kaplan-Meier survival after reoperation for failed stentless valve was 83% (95% confidence interval: 73% to 89%) and 57% (95% confidence interval: 36% to 74%).

CONCLUSIONS

Aortic valve reoperation after stentless valve implantation can be performed with low operative mortality and favorable long-term survival.

Those who do not remember the past are condemned to repeat it

Transcatheter aortic valve replacement (TAVR) for aortic valve stenosis has rapidly progressed from its initial application in the inoperable or high-risk patients to those determined to be intermediate and low risk. It is our concern this has occurred without adequate knowledge or examination of the long-term durability of TAVR valves and the impact on subsequent aortic valve surgery, should it be required. In this editorial, we provide insight and reflect upon lessons learned from past surgical techniques and their subsequent abandonment.

Perceval valve-in-valve implant for full root xenograft failure

Aortic root replacement with a biological conduit results in excellent hemodynamics but has limited durability. We report a series of six patients who underwent successful Perceval-S surgical aortic valve implantation following surgical deterioration of a biological valve composite conduit and discuss the technical details and the importance of appropriate valve sizing for this procedure.

Current indications for stentless aortic bioprostheses

The best aortic prostheses have been debated for decades. The introduction of stentless aortic bioprostheses was aimed at improving hemodynamics and potentially the durability of aortic bioprostheses. Despite the good short- and long-term outcomes after implantation of stentless aortic bioprostheses, their use remains limited owing to the technically demanding implantation techniques. Nevertheless, stentless aortic bioprostheses might be of special benefit in certain indications, where they could be a valuable addition to the surgical armamentarium.

Risks and Challenges of Surgery for Aortic Prosthetic Valve Endocarditis

BACKGROUND

Prosthetic valve endocarditis is the most severe form of infective endocarditis. This study assessed the risks and challenges of surgery for aortic prosthetic valve endocarditis.

METHODS

In total, 116 consecutive patients (98 males, age 65.2±12.7years), who underwent redo-surgery for active aortic prosthetic valve endocarditis between 2000 and 2014, were reviewed. Cox regression analysis was used to identify factors for aortic root destructions as well as for morbidity and mortality. Median follow-up was 3.8 years (0-13.9 years).

RESULTS

Aortic root destructions (42 limited and 29 multiple lesions) were associated with early prosthetic valve endocarditis and delayed diagnosis (≥14 d), but not with mortality. There were 16 (13.8%) early (≤30 d) and 32 (27.6%) late (>30 days) deaths. Survival at 1, 5, and 10 years was 72±4.3%, 56±5.4%, and 46±6.4%, respectively. The cumulative incidence of death, reinfection, and reoperation was 19.0% at 30days and 36.2% at 1year. Delayed diagnosis, concomitant procedures, and EuroSCORE II >20% were predictors for early mortality and need for mechanical circulatory support, age >70years, and critical preoperative state were predictors for late mortality. In their absence, survival at 10 years was 70±8.4%. Reinfections and reoperations occurred more frequently if ≥1 risk factor for endocarditis and aortic root destructions were present. At 10 years, freedom from reinfection and reoperation was 89±4.2% and 91±4.0%.

CONCLUSIONS

The risks of death, reinfection, and reoperation are significant within the first year after surgery for aortic prosthetic valve endocarditis. Early diagnosis and aortic root destructions are the most important challenges, but advanced age, critical preoperative state, and the need for mechanical circulatory support determine long-term survival.

Ascending Aortic Replacement and Sutureless Valve in a Failed Stentless Aortic Prosthesis: A Bailout Option

Aortic valve replacement with a Perceval sutureless bioprosthesis is a viable rescue option for a failed aortic stentless prosthesis. However, a dilated sinotubular junction and ascending aorta are reported as a contraindication for this technique. We describe an aortic sutureless valve implantation in a patient with a dilated ascending aorta and small aortic root after Dacron graft replacement of the ascending aorta in a failed aortic stentless bioprosthesis.

High-risk Trans-Catheter Aortic Valve Replacement in a Failed Freestyle Valve with Low Coronary Height: A Case Report

A 55-year-old male with a history of two prior cardiac surgeries presented with decompensated heart failure due to severe bioprosthetic aortic valve insufficiency. A third operation was viewed prohibitively high risk and valve-in-valve trans-catheter aortic valve replacement was considered. There were however several high-risk features and technically challenging aspects including low coronary ostia height, poor visualization of the aortic sinuses, and difficulty in identification of the coplanar view due to severe aortic insufficiency, and a highly mobile aortic valve mass. After meticulous peri-procedural planning, trans-catheter aortic valve replacement was carried out with a SAPIEN 3 balloon-expandable valve without any complication. Strategies undertaken to navigate the technically challenging aspects of the case are discussed.

Perceval S Valve Solution for Degenerated Freestyle Root in the Presence of Chronic Aortic Dissection

Aortic root replacement with porcine xenograft is a valuable treatment option in acute aortic dissection, but conduits are often prone to degeneration. Reoperation is still associated with high operative mortality, and it usually requires root removal and repetition of the Bentall procedure, or a less radical option limited to valve replacement. We describe two cases of Freestyle root degeneration in patients with chronic aortic dissection, in whom we performed a valve-in-valve procedure with the Perceval S prosthesis (Sorin Group, Saluggia, Italy).

Surgical management of destructive aortic endocarditis: left ventricular outflow reconstruction with the Sorin Pericarbon Freedom stentless bioprosthesis†

OBJECTIVES

The treatment of complicated aortic endocarditis with periannular abscesses and root disarrangement is a surgical challenge, and includes left ventricular outflow tract (LVOT) reconstruction with the patch technique or homograft implantation. The results of a simplified technique to reconstruct the LVOT in destructive endocarditis of either the aortic native valve or valve prosthesis with the Sorin Pericarbon Freedom stentless valve are reported.

METHODS

Since August 2007, 40 patients with destructive endocarditis (mean age: 69 ± 12, 75% males, European System for Cardiac Operative Risk Evaluation II (EuroSCORE II): 19 ± 13, New York Heart Association (NYHA) class: ≥3 in all cases) have undergone LVOT reconstruction with a Sorin Pericarbon Freedom stentless bioprosthesis. Seven patients (17.5%) were in septic or cardiogenic shock preoperatively, and 18 patients (45%) suffered from moderate or severe aortic regurgitation. Eleven patients (27.5%) experienced preoperative systemic embolizations. Thirty-six cases (90%) were valve redos and 9 patients (22.5%) had concomitant procedures. The mean follow-up was 26 ± 25 months.

RESULTS

One patient (2.5%) died early (<30 days) and another 3 patients never discharged died due to multiorgan failure and septic shock. Actuarial survival rate was 85 ± 6% at 1 year, and 76 ± 8% at 3 and 5 years, respectively. Twelve patients (30%) required pacemaker implantation because of atrioventricular block and 20 patients (50%) developed or showed a progression of renal failure. One patient (2.5%) had an endocarditis relapse, and 1 (2.5%) showed a mild paraprosthetic aortic leak. No patient needed reoperation. At the last echocardiographic evaluation, mean gradient, peak gradient and left ventricular ejection fraction were 7.9 ± 5.0 mmHg, 15.1 ± 7.2 mmHg and 63.3 ± 9.3%, respectively.

CONCLUSIONS

The Sorin Pericarbon Freedom stentless prosthesis, with the modified technique herein described, seems to be a good option in most of cases of destructive aortic valve endocarditis. It is promptly available in different sizes, easy to implant and, due to its pericardial inflow skirt, ideal for extensive reconstruction of the LVOT with good haemodynamic performance and low risk of relapse.

Early hemodynamic performance of the third generation St Jude Trifecta aortic prosthesis: A systematic review and meta-analysis

OBJECTIVE

The Trifecta aortic prosthesis is a latest-generation trileaflet stented pericardial valve designed for supra-annular placement in the aortic position. Robust clinical evidence and long-term follow-up data for this new prosthesis are lacking; a systematic review was conducted to assess current evidence.

METHODS

A comprehensive search from 6 electronic databases was performed, with time period parameters dating from database inception to January 2014. Results utilizing Trifecta prosthesis for aortic valve replacement (AVR) were identified.

RESULTS

A total of 13 studies with 2549 patients undergoing AVR with this prosthesis were included in this review. The mean proportion of patients with aortic stenosis was 82.4%, with a mean gradient of 47.4 mm Hg, and a pooled effective orifice area (EOA) of 0.74 cm(2). Valve sizes of 21 mm and 23 mm were implanted in 71.3% of patients. The pooled rates of 30-day mortality, cerebrovascular accidents, and acute kidney injuries were 2.7%, 1.9%, and 2.6%, respectively. After implantation, the pooled mean gradient decreased to 9.2 mm Hg, whereas discharge EOA increased to 1.8 cm(2), compared with preoperative parameters. Among included studies with significant heterogeneity detected, most patients had satisfactory patient-prosthesis mismatch, with 2.7% having severe mismatch.

CONCLUSIONS

The present systematic review demonstrated that short-term AVR with this prosthesis provided excellent early safety and hemodynamic outcomes with acceptable mean gradients and EOA. Long-term follow-up and randomized controlled trials are warranted to confirm the early results.

Commissural detachment and Valsalva sinus dilatation after implantation of Prima Plus stentless valve with full root technique

The stentless aortic bioprosthesis has been used because of its excellent hemodynamics and few valve-related complications. We report a case of redo aortic root replacement for severe aortic regurgitation and dilatation of the Valsalva sinus 7 years after the implantation of a Prima Plus aortic root bioprosthesis (Edwards LifeScience, Irvine, CA, USA) using a full root technique. Intraoperative findings showed the complete detachment of the commissure between the left and non-coronary cusps, and Valsalva sinus dilatation of the porcine aortic root bioprosthesis. Redo aortic root replacement with a 23-mm porcine bioprosthesis and 28-mm straight graft was performed. There were no findings of intimal tear, suture dehiscence, degeneration, and perforation of the bioprosthesis. Such complications associated with the Edwards Prima Plus aortic root bioprosthesis were rarely reported. Commissural detachment of a porcine stentless aortic bioprosthesis can occur; thus, careful follow-up involving echocardiography and computed tomography is necessary.