A cost-utility analysis of transcatheter versus surgical aortic valve replacement for the treatment of aortic stenosis in the population with intermediate surgical risk

A Systematic Review and Statistical Analysis of Factors Influencing the Cost-Effectiveness of Transcatheter Aortic Valve Implantation for Symptomatic Severe Aortic Stenosis

Objective

Transcatheter aortic valve implantation (TAVI) is a disruptive technology recommended for patients with symptomatic severe aortic stenosis (sSAS). Despite being available for over 15 years in Europe, with an extensive volume of clinical and economic evaluations across all surgical risk groups, there is little evidence on the identification of the key drivers of TAVI's cost-effectiveness. This study sought to identify these factors and quantify their role.

Methods

A systematic literature review was conducted to identify published economic evaluations of TAVI. This was supplemented by health technology assessment reports. The primary outcome was the likelihood of TAVI being found cost-effective. Secondary outcomes of TAVI being dominant, and the incremental health benefits of TAVI were also explored.

Results

Forty-two studies, reporting 65 unique analyses, were identified. TAVI was found to be cost-effective and dominant in 74% and 20% of analyses, respectively. The latest generation balloon-expandable TAVI device (SAPIEN 3) was more likely to be found cost-effective, as was TAVI use in low-risk populations and when performed via transfemoral access route. There was heterogeneity in the approach taken to economic modelling, which may also influence estimates of cost-effectiveness. Analyses that found TAVI to be dominant always compared it to surgery and usually considered the latest generation balloon-expandable TAVI device. Largest health benefits were observed for the inoperable risk group.

Conclusion

For patients with sSAS, TAVI is typically a cost-effective treatment option. There are important differences by device generation, risk group and access route. It is crucial to consider these differences when appraising the health economic evidence-base for TAVI.

Transcatheter aortic valve implantation in patients with severe symptomatic aortic valve stenosis: systematic review of cost-effectiveness analysis

BACKGROUND

Transcatheter aortic valve implantation (TAVI) is a less invasive and costly treatment for patients with severe aortic stenosis (AS). This study aimed to systematically review the published literature focusing on economic evaluation of TAVI compared with other alternative treatments in AS populations.

METHODS

A systematic review was conducted from inception until May 2021 using PubMed, Scopus, Web of science and Embase databases. The qualities of included studies were evaluated using Consolidated Health Economic Evaluation Reporting Standard (CHEERS) criteria. Data of costs, outcomes, incremental cost-effectiveness ratio (ICER) and willingness to pay were extracted. To compare results, ICERs were converted to the 2020 United States dollar (USD) rate.

RESULTS

Of the 29 included cost-effectiveness studies, TAVI was cost-effective in all studies in the low-risk group (3/3), 77% of studies (7/9) in the intermediate-risk group, half of the studies (6/12) in the high-risk group, and 83% of studies (10/12) in the inoperable group. When adjusted to USD 2020, ICERs ranged from USD 2741 to 1027,674 USD per quality-adjusted life-year gained. The overall quality of the studies ranged from moderate to high.

CONCLUSIONS

TAVI is potentially a cost-effective alternative to surgical aortic valve replacement (SAVR) for patients with operable AS with low, intermediate or high risk compared with medical management (MM) for patients with inoperable AS. TAVI was associated with a significant gain in quality-adjusted life-years in almost all studies compared to either SAVR or MM. TAVI is a costly procedure; therefore, justifying its cost-effectiveness depends on the acceptable threshold in each country.

Incorporating economic analysis in interventional cardiology research

Evaluative research in interventional cardiology has focused on clinical and technical outcomes. Inclusion of economic data can enhance evaluative research by quantifying the relative economic burden incurred by different therapies. When combined with clinical outcomes, cost data can provide a measure of value (e.g., marginal cost-effectiveness). In some select situations, cost data can also be used as surrogates for complexity of care and morbidity. In this narrative review, we aim to provide a framework for the application of cost data in clinical trials and observational research, detailing how to incorporate this kind of data into interventional cardiology research.

Outcome and Cost Comparisons Between Surgical and Transcatheter Aortic Valve Replacements

OBJECTIVE

Surgical aortic valve replacement (SAVR) has been the standard of care for severe aortic stenosis. In 2019, annual transcatheter aortic valve replacement (TAVR) implantations surpassed SAVR. We compared in-hospital costs and outcomes between these two procedures.

METHODS

A single-center retrospective review was performed of patients who underwent isolated SAVR or TAVR from October 2013 to December 2019. Baseline patient characteristics, operating room (OR) time, intensive care unit (ICU) length of stay (LOS), total LOS, cumulative cost, and complication rates were collected. Propensity matching was performed to identify differences in costs and outcomes between comparable groups.

RESULTS

There were 515 patients who met inclusion criteria. TAVR was performed in 402 patients, while SAVR was performed in 113. Propensity matching resulted in 82 matched pairs. The SAVR cohort more frequently spent >1 day in the ICU, had longer total hospital LOS, longer OR time, and higher hospitalization cost. However, TAVR was associated with higher mean OR cost and higher valve cost. The cumulative index admission costs were not significantly different between groups. TAVR patients had less postoperative atrial fibrillation but more frequent pacemaker placement. One-year mortality was similar between SAVR (2.4%) and TAVR (3.8%), but 3-year (5.8% vs 19.2%) and 5-year (5.8% vs 37.2%) mortality favored SAVR.

CONCLUSIONS

In propensity-matched groups, TAVR was associated with shorter ICU and hospital LOS and OR times but increased permanent pacemaker rates. In addition, while 1-year survival was similar between groups, SAVR had significantly improved 3-year and 5-year survival.

Monitored Anesthesia Care Versus General Anesthesia for Transcatheter Aortic Valve Replacement

OBJECTIVE

Monitored anesthesia care (MAC) has been increasingly used in lieu of general anesthesia (GA) for transcatheter aortic valve replacement (TAVR). We sought to compare outcomes and in-hospital costs between MAC and GA for TAVR at a Veterans Affairs Medical Center.

METHODS

A single-center retrospective review was performed of 349 patients who underwent transfemoral TAVR (MAC, n = 244 vs GA, n = 105) from January 2014 to December 2019. Baseline patient characteristics, operating room (OR) time, intensive care unit (ICU) length of stay (LOS), and cost, total LOS, hospital cost, total cost, and complication rates were collected. Propensity matching was performed and resulted in 83 matched pairs.

RESULTS

In the unmatched TAVR cohort, MAC TAVR was associated with reduced OR time (146 vs 198 min, P < 0.001), ICU LOS (1.4 vs 1.8 days, P < 0.001), total hospital LOS (3.4 vs 5.4 days, P < 0.001), and lower index total cost ($81,300 vs $85,400, P = 0.010). After propensity matching, MAC TAVR patients had reduced OR time (146 vs 196 min, P < 0.05), ICU LOS (1.2 vs 1.7 days, P = 0.006), total LOS (3.5 vs 5.1 days, P = 0.001), and 180-day mortality (2.4% vs 12%, P < 0.03). There was no difference in total hospitalization cost or total cost.

CONCLUSIONS

In propensity-matched groups, TAVR utilizing MAC is associated with improved OR time efficiency, decreased LOS, and a reduction in 180-day mortality but no significant difference in cost.

Cost-effectiveness of transcatheter aortic valve implantation in patients with severe symptomatic aortic stenosis of intermediate surgical risk in Singapore

Objective

The objective was to assess the cost-effectiveness of transcatheter aortic valve implantation (TAVI) in patients with severe aortic stenosis with intermediate surgical risk in Singapore.

Methods

A de novo Markov model with three health states – stroke with long-term sequelae, no stroke, and death – was developed and simulated using Monte Carlo simulations with 10,000 iterations over a five-year time horizon from the Singapore healthcare system perspective. A 3% annual discount rate for costs and outcomes and monthly cycle lengths were used. By applying the longest available published clinical evidence, simulated patients received either TAVI or surgical aortic valve replacement (SAVR) and were at risk of adverse events (AEs) such as moderate-to-severe paravalvular aortic regurgitation (PAR).

Results

When five-year PARTNER 2A data was applied, base-case analyses showed that the incremental cost-effectiveness ratio (ICER) for TAVI compared to SAVR was US$315,760 per quality-adjusted life year (QALY) gained. The high ICER was due to high incremental implantation and procedure costs of TAVI compared to SAVR, and marginal improvement of 0.10 QALYs as simulated mortality of TAVI exceeded SAVR at 3.75 years post-implantation. One-way sensitivity analysis showed that the ICERs were most sensitive to cost of PAR, utility values of SAVR patients, and cost of TAVI and SAVR implants and procedures. When disutilities for AEs were additionally applied, the ICER decreased to US$300,070 per QALY gained. TAVI was dominated by SAVR when the time horizon increased to 20 years. Clinical outcomes projected from one-year PARTNER S3i data further reduced the ICER to US$86,337 per QALY gained for TAVI, assuming early all-cause mortality benefits from TAVI continued to persist. This assumption was undermined when longer term data showed that TAVI’s early mortality benefits diminished at five years.

Limitations and conclusion

TAVI is unlikely to be cost-effective in intermediate surgical-risk patients compared to SAVR in Singapore.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-022-08369-5.

Economic Evaluation of Transcatheter Aortic Valve Replacement Compared to Surgical Aortic Valve Replacement in Chinese Intermediate-Risk Patients

Background

Aortic stenosis (AS) is a severe disease that causes heart failure and sudden death. Transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR) are both recommended for patients with intermediate surgical risk, but the cost-effectiveness of TAVR compared to SAVR in China has not been investigated.

Methods

A combined decision tree and Markov model were conducted to compare the cost-effectiveness of TAVR versus SAVR with a 5-year simulation. The primary outcome was the incremental cost-effectiveness ratio (ICER), a ratio of incremental costs to incremental quality-adjusted life-year (QALY). One-way sensitive analysis and probabilistic sensitivity analysis (PSA) were conducted to test the robustness of the model.

Results

After a simulation of 5 years, the costs of TAVR and SAVR were 54,573 and 35,002 USD, respectively, and the corresponding effectiveness was 2.826 versus 2.712 QALY, respectively. The ICER for the TAVR versus SAVR comparison was 170,056 USD/QALY, which was three times higher than the per capita gross domestic product (GDP) in China. One-way sensitive analysis showed that the cost of the TAVR device impacted the ICER. The TAVR could be cost-effective only in the case where its cost is lowered to 29,766 USD.

Conclusion

TAVR is currently not cost-effective in China, but it could be cost-effective with a reduction of costs to 29,766 USD, which is approximately 65% of the current price.

Financial Incentives for Transcatheter Aortic Valve Implantation in Ontario, Canada: A Cost-Utility Analysis

Background

Transcatheter aortic valve implantation (TAVI) is a minimally invasive therapy for patients with severe aortic stenosis, which has become standard of care. The objective of this study was to determine the maximum cost‐effective investment in TAVI care that should be made at a health system level to meet quality indicator goals.

Methods and Results

We performed a cost‐utility analysis using probabilistic patient‐level simulation of TAVI care from the Ontario, Canada, Ministry of Health perspective. Costs and health utilities were accrued over a 2‐year time horizon. We created 4 hypothetical strategies that represented TAVI care meeting ≥1 quality indicator targets, (1) reduced wait times, (2) reduced hospital length of stay, (3) reduced pacemaker use, and (4) combined strategy, and compared these with current TAVI care. Per‐person costs, quality‐adjusted life years, and clinical outcomes were estimated by the model. Using these, incremental net monetary benefits were calculated for each strategy at different cost‐effectiveness thresholds between $0 and $100 000 per quality‐adjusted life year. Clinical improvements over the current practice were estimated with all comparator strategies. In Ontario, achieving quality indicator benchmarks could avoid ≈26 wait‐list deaths and 200 wait‐list hospitalizations annually. Compared with current TAVI care, the incremental net monetary benefit for this strategy varied from $10 765 (±$8721) and $17 221 (±$8977). This would translate to an annual investment of between ≈$14 to ≈$22 million by the Ontario Ministry of Health to incentivize these performance measures being cost‐effective.

Conclusions

This study has quantified the modest annual investment required and substantial clinical benefit of meeting improvement goals in TAVI care.

Impact of Atrial Fibrillation on Outcomes of Aortic Valve Implantation

New or preexisting atrial fibrillation (AF) is frequent in patients undergoing aortic valve replacement. We evaluated whether the presence of AF during transcatheter aortic valve implantation (TAVI) or surgical aortic valve replacement (SAVR) impacts the length of stay, healthcare adjusted costs, and inpatient mortality. The median length of stay in the patients with AF increased by 33.3% as compared with those without AF undergoing TAVI and SAVR (5 [3 to 8] days vs 3 [2 to 6] days, p <0.0001 and 8 [6 to 12] days vs 6 [5 to 10] days, p <0.0001, respectively). AF increased the median value of adjusted healthcare associated costs of both TAVI ($46,754 [36,613 to 59,442] vs $49,960 [38,932 to 64,201], p <0.0001) and SAVR ($40,948 [31,762 to 55,854] vs $45,683 [35,154 to 63,026], p <0.0001). The presence of AF did not independently increase the in-hospital mortality. In conclusion, in patients undergoing SAVR or TAVI, AF significantly increased the length of stay and adjusted healthcare adjusted costs but did not independently increase the in-hospital mortality.

The cost-effectiveness of transcatheter aortic valve implantation: exploring the Italian National Health System perspective and different patient risk groups

OBJECTIVES

To assess the cost-effectiveness (CE) of transcatheter aortic valve implantation (TAVI) in Italy, considering patient groups with different surgical risk.

METHODS

A Markov model with a 1-month cycle length, comprising eight different health states, defined by the New York Heart Association functional classes (NYHA I-IV), with and without stroke plus death, was used to estimate the CE of TAVI for intermediate-, high-risk and inoperable patients considering surgical aortic valve replacement or medical treatment as comparators according to the patient group. The Italian National Health System perspective and 15-year time horizon were considered. In the base-case analysis, effectiveness data were retrieved from published efficacy data and total direct costs (euros) were estimated from national tariffs. A scenario analysis considering a micro-costing approach to estimate procedural costs was also considered. The incremental cost-effectiveness ratio (ICER) was expressed both in terms of costs per life years gained (LYG) and costs per quality adjusted life years (QALY). All outcomes and costs were discounted at 3% per annum. Univariate and probabilistic sensitivity analyses (PSA) were performed to assess robustness of results.

RESULTS

Over a 15-year time horizon, the higher acquisition costs for TAVI were partially offset in all risk groups because of its effectiveness and safety profile. ICERs were €8338/QALY, €11,209/QALY and €10,133/QALY, respectively, for intermediate-, high-risk and inoperable patients. ICER values were slightly higher in the scenario analysis. PSA suggested consistency of results.

CONCLUSIONS

TAVI would be considered cost-effective at frequently cited willingness-to-pay thresholds; further studies could clarify the CE of TAVI in real-life scenarios.

Transcatheter Aortic Valve Implantation (TAVI) Versus Surgical Aortic Valve Replacement for Aortic Stenosis (SAVR): A Cost-Comparison Study

BACKGROUND

Comparative costing studies using real-world data stratified by patient case-mix, are valuable to decision makers for making reimbursement decisions of new interventions. This study evaluated real-world hospital admissions and short-term costs of transcatheter aortic valve implantation (TAVI) and isolated surgical aortic valve replacement (SAVR) for patients with aortic stenosis, stratified by the Society of Thoracic Surgeons (STS) risk scores.

METHODS

Retrospective analysis of consecutive patients with a principal diagnosis of aortic stenosis who underwent isolated valve replacement at a single tertiary hospital, January 2012-December 2017. Patients were followed-up for 30 days post-procedure or until hospital discharge if index hospitalisation was greater than 30 days. Intensive care unit (ICU) and hospital length of stay (days), and costs in 2018 Australian dollars for the index procedure and 30-day follow-up were assessed. Multivariable generalised linear and two-part models with gamma distribution and log link function adjusting for Society of Thoracic Surgeons (STS) risk group and key sociodemographic characteristics were used.

RESULTS

Of 488 patients, 61% males, median age 78 years (IQR 14 years), 221 (45%) received transcatheter aortic valve replacement (TAVI) and 267 (55%) received surgical aortic valve replacement (SAVR). STS risk scores were low (28%), intermediate (46%) and high (26%) for TAVI patients, and low (85%), intermediate (12%) and high (3%) for SAVR patients. When adjusted, TAVI length of stay was 57% shorter than SAVR (95% CI 31-83%, p<0.001) for intensive care unit (ICU) admission, and 64% shorter (95% CI 47-81%, p<0.001) for hospital admissions. TAVI costs were 13% lower than SAVR (95% CI 4-22%, p=0.005).

CONCLUSION

This data suggests short-term health care costs are lower for patients with aortic stenosis undergoing TAVI than SAVR. A further roll-out of the TAVI program in hospitals across Australia may result in savings to the health system.

The Use of Decision Analytic Modeling in the Evaluation of Surgical Innovations: A Scoping Review

OBJECTIVES

The main objective of this review was to map how decision analytic models are used in surgical innovation (in which research phase, with what aim) and to understand how challenges related to the assessment of surgical interventions are incorporated.

METHODS

We systematically searched PubMed, Embase, and the Cochrane Library for studies published in 2018. We included original articles using a decision analytic model to compare surgical strategies. We included modeling studies of surgical innovations. General, innovation, and modeling characteristics were extracted, as were outcomes, recommendations, and handling of challenges related to the assessment of surgical interventions (learning curve, incremental innovation, dynamic pricing, quality variation, organizational impact).

RESULTS

We included 46 studies. The number of studies increased with each research phase, from 4% (n = 2) in the preclinical phase to 40% (n = 20) in phase 3 studies. Eighty-one studies were excluded because they investigated established surgical procedures, indicating that modeling is predominantly applied after the innovation process. Regardless of the research stage, the aim to determine cost-effectiveness was most frequently identified (n = 40, 87%), whereas exploratory aims (eg, exploring when a strategy becomes cost-effective) were less common (n = 9, 20%). Most challenges related to the assessment of surgical interventions were rarely incorporated in models (eg, learning curve [n = 1, 2%], organizational impact [n = 2, 4%], and incremental innovation [n = 1, 2%]), except for dynamic pricing (n = 10, 22%) and quality variation (n = 6, 13%).

CONCLUSIONS

In surgical innovation, modeling is predominantly used in later research stages to assess cost-effectiveness. The exploratory use of modeling seems still largely overlooked in surgery; therefore, the opportunity to inform research and development may not be optimally used.

Transcatheter aortic valve implantation in low-risk patients: A case of rational over exuberance. The time is not now

BACKGROUND

Review of evidence and concerns, relating to extension of transcatheter aortic valve implantation usage to low-risk patients.

METHODS

Comprehensive literature review was conducted identifying articles relating to transcatheter aortic valve implantation.

RESULTS

Transcatheter aortic valve implantation is effective in patients with aortic stenosis. Currently, long-term durability and cost-effectiveness are unproven, anticoagulation requirement undefined, permanent pacemaker implantation and paravalvular leak rates higher than following surgical aortic valve replacement.

CONCLUSIONS

Current evidence supporting transcatheter aortic valve implantation usage in low-risk patients is insufficient. Extending use now, to this large young patient population is premature, and should be delayed.

Real-World Health-Economic Considerations Around Aortic-Valve Replacement in a Publicly Funded Health System

Herein, we describe the unique interplay among biomedical ethics, principles of distributive justice, and economic theory to highlight the role of health technology assessments to compare therapeutic options for aortic valve replacement. From the perspective of the Canadian health care system, transcatheter aortic-valve implantation is associated with higher costs but also higher incremental health benefits compared with surgical aortic-valve replacement. At current willingness to pay thresholds, transcatheter aortic-valve replacement is likely cost effective across the spectrum of risk, from inoperable patients to those at low surgical risk. However, we highlight the nuances within each subgroup of surgical risk that merit careful consideration by the heart team. Moreover, incorporation of patients and their preferences in decision-making is key. In particular, in young, low-risk patients, there remains uncertainty regarding the optimal treatment, with unique concerns around valve durability, selection of valve prosthesis, and consideration for special procedures such as the Ross procedure. Nonetheless, current research suggests that, universally, patients prefer a less invasive approach compared with a more invasive approach. Finally, we highlight that there remain critical issues around timeliness of access to care and unacceptable geographic inequities across Canada. Further research into alternative funding mechanisms and integrated cross-sector care pathways is necessary to address these issues.

One-Year Costs Associated with Hospitalizations Due to Aortic Stenosis in Canada

Background

There is a lack of data on the burden of patients hospitalized with aortic stenosis (AS) in Canada. The primary study objective was to document the index and 1-year costs of hospitalized patients with AS in Canada. Secondary objectives were to explore results by treatment modality and Canadian provinces.

Methods

Hospitalized patients with a most responsible diagnosis (MRD) of AS during fiscal year 2014/2015 were identified using Canadian administrative databases. Costs were calculated for the index admission and for up to 1 year. For our secondary analyses, patients were classified according to the intervention received: surgical aortic valve replacement (SAVR), SAVR with coronary artery bypass graft, or transfemoral or transapical transcatheter aortic valve implantation. Hospitalized AS patients who did not undergo SAVR or transcatheter aortic valve implantation were classified as the untreated group. The data were also analyzed by Canadian provinces.

Results

During fiscal year 2014/15, a total of 7217 Canadians were hospitalized with an MRD of AS. The mean (standard deviation) age of our population was 74.2 (11.5) years, and 39% were female. The 1-year hospital costs associated with an MRD of AS in Canada were calculated at $393 million. Our secondary analyses suggest that patient demographics (mean age ranging from 69 to 82 years) and outcomes (median length of stay ranging from 6 to 12 days) differ among treatment modalities and Canadian provinces.

Conclusions

AS hospitalizations result in a significant cost burden in Canada. Future research is needed to better understand variation among treatment modalities and Canadian provinces.

Cost-Effectiveness of Transcatheter Versus Surgical Aortic Valve Replacement in Low-Risk Patients With Severe Aortic Stenosis

BACKGROUND

Recent studies have shown that transcatheter aortic valve implantation (TAVI) is non-inferior to surgical aortic valve replacement (SAVR) for treatment of low-risk patients with severe aortic stenosis (AS). However, the cost-effectiveness of TAVI in this population is unknown. We sought to evaluate the cost-effectiveness of both balloon-expandable and self-expanding TAVI compared to SAVR in patients with severe AS at low operative risk.

METHODS

We developed a Markov model comparing TAVI to SAVR over a lifetime horizon. Key data inputs were drawn from the Placement of AoRTic TraNscathetER Valve (PARTNER) 3 trial for balloon-expandable TAVI and the Evolut Low-Risk trial for self-expanding TAVI. Costs were obtained from Australian sources. The perspective was that of the Australian health care system.

RESULTS

Although procedural costs were higher for TAVI compared to SAVR, these were offset by a shorter length of hospitalisation and lower acute complication costs in the TAVI group. Over a lifetime horizon, balloon-expandable TAVI was associated with increased costs of A$702 compared to SAVR, and increased quality-adjusted survival by 0.20 years, yielding an incremental cost-effectiveness ratio of A$3,521 per quality-adjusted life year (QALY) saved. Self-expanding TAVI was associated with lower lifetime costs compared to SAVR, and increased quality-adjusted survival by 0.08 years, and was therefore economically dominant. In probabilistic sensitivity analyses, balloon-expandable TAVI was cost-effective in 78% of iterations (at a cost-effectiveness threshold of A$50,000 per QALY gained) and self-expanding TAVI was cost-effective in 70% of iterations.

CONCLUSIONS

Among low-risk AS patients, both balloon-expandable and self-expanding TAVI are likely to be cost-effective relative to SAVR.

Decision analysis and personalized clinical tool for cerebrospinal fluid drains in thoracoabdominal aortic aneurysms repair

BACKGROUND AND AIM

The routine use of cerebrospinal fluid (CSF) drainage in patients undergoing operative repair of thoracoabdominal aneurysms (TAAA) has been associated with decreased rates of spinal cord ischemia. The use of CSF drains is not without consequence, however with complications including subarachnoid hemorrhage, epidural hematoma, meningitis, and, in 1% of cases, death. To date, a decision analysis tool to help clinicians decide when to use and not to use a CSF drain does not exist. In this analysis, we set out to develop a decision analysis tool for CSF drain placement in patients undergoing operative repair of TAAA.

METHODS

A Markov state-transition cohort model that compared TAAA repair with adjunctive CSF drain insertion to TAAA repair without drain insertion for the outcome of life expectancy was developed in TreeAge 2020. The cycle length was 1 month and the time horizon was 60 months.

RESULTS

The use of a CSF drain was associated with improved 5-year life expectancy (3.21 ± 0.10 vs. 3.09 ± 0.11 life-years gained). In the sensitivity analysis that varied the effectiveness of a CSF drain (odds ratio closer to 1 = less effective), the use of a CSF drain resulted in higher life expectancy in almost all scenarios.

CONCLUSIONS

The routine use of a CSF drain in patients undergoing TAAA repair is safe and effective, with few exceptions. This decision analysis tool can be used by clinicians to develop a personalized approach.

Next-generation tissue-engineered heart valves with repair, remodelling and regeneration capacity

Valvular heart disease is a major cause of morbidity and mortality worldwide. Surgical valve repair or replacement has been the standard of care for patients with valvular heart disease for many decades, but transcatheter heart valve therapy has revolutionized the field in the past 15 years. However, despite the tremendous technical evolution of transcatheter heart valves, to date, the clinically available heart valve prostheses for surgical and transcatheter replacement have considerable limitations. The design of next-generation tissue-engineered heart valves (TEHVs) with repair, remodelling and regenerative capacity can address these limitations, and TEHVs could become a promising therapeutic alternative for patients with valvular disease. In this Review, we present a comprehensive overview of current clinically adopted heart valve replacement options, with a focus on transcatheter prostheses. We discuss the various concepts of heart valve tissue engineering underlying the design of next-generation TEHVs, focusing on off-the-shelf technologies. We also summarize the latest preclinical and clinical evidence for the use of these TEHVs and describe the current scientific, regulatory and clinical challenges associated with the safe and broad clinical translation of this technology.

The cost-effectiveness of transcatheter aortic valve replacement in low surgical risk patients with severe aortic stenosis

Aims

The economic value of transcatheter aortic valve replacement (TAVR) in low surgical risk patients with severe, symptomatic aortic stenosis is not known. Our objective was to determine the cost-effectiveness of balloon-expandable TAVR and self-expandable TAVR relative to surgical aortic valve replacement (SAVR) in low-risk patients.

Methods and results

A fully probabilistic Markov cohort model was constructed to estimate differences in costs and effectiveness [quality-adjusted life years (QALYs)] over the patient’s life-time time from the third-party payer’s perspective. Clinical outcomes modelled were alive/well (no complications), permanent stroke, ≥moderate paravalvular leak, new pacemaker, rehospitalization, and death. A network meta-analysis of the PARTNER 3 and Evolut Low Risk trial was performed to compare balloon-expandable TAVR, self-expandable TAVR, and SAVR for the efficacy inputs. Incremental-cost effectiveness ratios (ICER) were calculated. The total life-time costs in the balloon-expandable TAVR, self-expandable-TAVR, and SAVR arms were $37  330 ± 4724, $39 660 ± 4862, and $34 583 ± 6731, respectively, and total life-time QALYs gained were 9.15 ± 3.23, 9.13 ± 3.23, and 9.05 ± 3.20, respectively. The ICERs for balloon-expandable TAVR and self-expandable TAVR against SAVR were $27 196/QALY and $59 641/QALY, respectively. Balloon-expandable TAVR was less costly and more effective than self-expandable TAVR. There was substantial uncertainty, with 53% and 58% of model iterations showing balloon-expandable TAVR to be the preferred option at willingness-to-pay thresholds of $50 000/QALY and $100  000/QALY, respectively.

Conclusion

Compared with SAVR, TAVR, particularly with balloon-expandable prostheses may be a cost-effective option for patients with severe aortic stenosis at low surgical risk.

Relative Costs of Surgical and Transcatheter Aortic Valve Replacement and Medical Therapy

Background:

The number of patients treated for aortic valve disease in the United States is increasing rapidly. Transcatheter aortic valve replacement (TAVR) is supplanting surgical aortic valve replacement (SAVR) and medical therapy (MT). The economic implications of these trends are unknown. Therefore, we undertook to determine the costs, inpatient days, and number of admissions associated with treating aortic valve disease with SAVR, TAVR, or MT.

Methods:

Using the Nationwide Readmissions Database, we identified patients with aortic valve disease admitted 2012 to 2016 for SAVR, TAVR, and disease symptoms (congestive heart failure, unstable angina, non–ST-elevation myocardial infarction, syncope). Patients not undergoing SAVR or TAVR were classified as receiving MT. Beginning with the index admission, we estimated inpatient costs, days, and admissions over 6 months.

Results:

Among 190 563 patients with aortic valve disease, the average aggregate 6-month inpatient costs were $59 743 for SAVR, $64 395 for TAVR, and $23 460 for MT. Mean index admission was longer for SAVR (10.0 days) than for TAVR (7.0 day) or MT (5.3 days), but the average number of unplanned readmission inpatient days was 2.0 for SAVR, 3.0 for TAVR, and 4.3 for MT; the average number of total admissions was 1.3 for SAVR, 1.5 for TAVR, and 1.7 for MT ( P <0.01 for all). TAVR index admission costs decreased over time to become similar to SAVR costs by 2016.

Conclusions:

Aggregate costs were higher for TAVR than SAVR and were significantly more expensive than MT alone. However, TAVR costs decreased over time while SAVR and MT costs remained unchanged.

A Canadian cost-effectiveness analysis of SAPIEN 3 transcatheter aortic valve implantation compared with surgery, in intermediate and high-risk severe aortic stenosis patients

Background and objectives: The treatment of severe aortic stenosis requires replacement of the defective native valve. Traditionally, this has been done via surgery, but in the last 10 years, transcatheter techniques have emerged. Transcatheter aortic valve implantation (TAVI) is a less invasive option compared to surgical aortic valve replacement (SAVR), and this study evaluates the cost-effectiveness of TAVI versus SAVR in intermediate and high surgical risk patients in Canada. Methods: A Markov model was used to project the costs and quality-adjusted life years (QALYs) gained for TAVI using the SAPIEN 3 valve and SAVR over a 15-year time horizon. The PARTNER I and II studies were used to populate the model in terms of survival, clinical event rates and quality of life over time. The costs of TAVI with SAPIEN 3 and SAVR as well as the costs associated with events included in the model were derived from Canadian administrative and literature data. Costs were expressed in 2018 Canadian dollars and all future costs and QALYs were discounted at a rate of 1.5% annually. Probabilistic and one-way sensitivity analyses were conducted. Results: The incremental cost-effectiveness ratios of TAVI using the SAPIEN 3 valve compared to surgery were $28,154 per QALY gained in intermediate risk patients and $17,237 per QALY gained in high-risk patients. The results of the probabilistic analyses indicated that at willingness-to-pay threshold of $50,000 per QALY gained, the probability of TAVI to be cost-effective was greater than 0.9 in both intermediate-risk and high-risk patients. Sensitivity analyses showed the results were most sensitive to the time horizon used. Conclusion: TAVI using the SAPIEN 3 valve is highly likely to be cost-effective in Canadian patients with severe aortic stenosis who are at intermediate and high surgical risk.

Transcatheter versus surgical aortic valve replacement in low and intermediate risk patients with severe aortic stenosis: systematic review and meta-analysis of randomized controlled trials and propensity score matching observational studies

Background

To compare the outcome of transcatheter aortic valve replacement (TAVR) with surgical aortic valve replacement (SAVR) in low and intermediate risk patients with severe aortic stenosis (AS). Randomized controlled trials (RCT) and propensity score matching (PSM) studies compare TAVR with SAVR in patients at low and intermediate surgical risk.

Methods

Two authors searched relevant literature independently, then extracted data from the included studies, and assessed risk of bias and quality of study separately according to different study designs, besides that, the extracted data was analyzed via utilization of GRADE system to evaluate the quality of evidence separately.

Results

Overall 15 studies (5 RCTs, 10 PSM studies) with total 12,057 patients were selected. Mortality and disabling stroke during follow-up period were comparable between TAVR and SAVR (RR 1.09, 95% CI: 0.81 to 1.46; RR 0.7, 95% CI: 0.45 to 1.07, respectively), TAVR revealed to be superior to SAVR regarding acute kidney injury (AKI), and onset of new atrial fibrillation (AF) (RCT: high certainty; AKI in PSM: moderate certainty, AF in PSM: low certainty). These results of RCT and PSM studies are consistent. In RCT review, SAVR was better in the following aspects: aortic valve (AV) re-intervention (high certainty), vascular complications, pacemaker implantation (moderate certainty), but comparable in the following aspects: myocardial infarction (MI), aortic insufficient (AI) (moderate certainty), major bleeding (low certainty). In PSM review, SAVR revealed a better result in AI and vascular complications (high certainty), but in the aspects of AV re-intervention, pacemaker implantation, major bleeding and MI (low certainty), it was comparable.

Conclusions

TAVR is comparable to SAVR in terms of mortality and disabling stroke in severe AS patients at low and intermediate risk, but higher proportion of AV re-intervention observed in TAVR. Those results should encourage caution when extending the indications of TAVR into low risk patients, especially for young low risk patients.

Systematic review registration

PROSPERO CRD 42018112626.

Cost-effectiveness analysis of the SAPIEN 3 TAVI valve compared with surgery in intermediate-risk patients

OBJECTIVE

Transcatheter aortic valve implantation (TAVI) has become the therapy of choice for treating severe aortic stenosis in patients at high-risk for surgery or where it is considered too risky to attempt. This uptake varies across geographies however, and its cost or value has frequently been cited as the reason for this. We sought to evaluate the potential cost and clinical impact of TAVI in intermediate risk patients from a French collective perspective.

MATERIALS AND METHODS

The analysis was performed using a novel Markov model with data derived from the PARTNER II randomized controlled trial for survival, clinical event rates, and quality-of-life. The simulated time horizon was 15 years, costs were from French sources and presented in 2016 Euros. Discounting of all outcomes was at 4% annually and the effect of uncertainty in model parameters was explored by deterministic and probabilistic sensitivity analysis (PSA).

RESULTS

In comparison to surgery, TAVI resulted in improved clinical outcomes (life expectancy and quality-adjusted life expectancy) and lower costs over a lifetime time horizon. The base case results showed increases of 0.42 years and 0.41 QALYs with lifetime cost savings of €439 for TAVI compared to surgery. PSA results showed a >50% likelihood of cost-effectiveness at €0 willingness-to-pay and a 100% likelihood at ∼€15,000.

LIMITATIONS

Clinically, survival projections are based on limited follow-up data and introduce uncertainty into the outcomes from the model. Economically, procedure costs are derived from a heterogeneous mix of patient risk groups, although this is much more likely to bias against TAVI and under-estimate overall cost savings.

CONCLUSIONS

In our analyses of intermediate risk patients, TAVI is associated with superior clinical outcomes compared to surgery and is cost saving. It could be expected that cost savings are conservative and likely to increase over time.

A comparative profitability analysis of transcatheter versus surgical aortic valve replacement in a high-volume French hospital

BACKGROUND

Current scientific guidelines have extended the indication for transcatheter aortic valve replacement (TAVR) to patients who present an intermediate risk for surgery and have been so far considered for conventional surgery. We previously demonstrated that the TAVR procedure generated profits despite elevated costs, but comparison with surgery has not been performed. The objective of this study was to assess the profitability of the TAVR procedure compared with conventional surgery in a high-volume French hospital. Consecutive patients eligible for transfemoral TAVR or surgical aortic valve replacement (SAVR) were included retrospectively in this single-centre study between September 2014 and December 2015. The primary endpoint was the profitability of each procedure (defined as the ratio between the profit and total revenues), calculated for each patient. Secondary composite endpoints included major adverse events in the 30 days following procedure and breakdown of costs.

RESULTS

Two hundred and thirty-eight patients were included in the TAVR group and 341 in the SAVR group. TAVR patients presented higher operative risk scores and more comorbidities. Compared with SAVR, TAVR was associated with higher profits (€2732 ± 1768 per patient vs. €2177 ± 2437 per patient, P < 0.001) but also higher costs (€27,778 ± 4961 vs. €17,813 ± 6071, P < 0.001) resulting in lower profitability (9.3 ± 5.7% vs. 11.7 ± 10.1%, P < 0.001). The price of the bioprosthesis represented 70% of the TAVR total cost.

CONCLUSIONS

TAVR performed in carefully selected patients was associated with higher profits than SAVR, but also higher costs resulting in lower profitability.

Cost-utility of surgical sutureless bioprostheses vs TAVI in aortic valve replacement for patients at intermediate and high surgical risk

BACKGROUND

Meta-analyses of studies comparing transcatheter aortic valve implants (TAVIs) and sutureless aortic valve replacement (SU-AVR) show differing effectiveness and safety profiles. The approaches also differ in their surgical cost (including operating room and device).

OBJECTIVE

The objective of this study was to assess the incremental cost-utility of SU-AVR vs TAVIs for the treatment of intermediate- to high-risk patients in the US, Germany, France, Italy, UK, and Australia.

METHODS

A patient-level simulation compares in-hospital pathways of patients undergoing SU-AVR or TAVIs; later, patient history is modeled at the cohort level. Hospital outcomes for TAVIs reproduce data from recent series; in SU-AVR patients, outcomes are obtained by applying relative efficacy estimates in a recent meta-analysis on 1,462 patients. After discharge, survival depends on the development of paravalvular leak and the need for dialysis. A comprehensive third-party payer perspective encompassing both in-hospital and long-term costs was adopted.

RESULTS

Due to lower in-hospital (4.1% vs 7.0%) and overall mortality, patients treated with SU-AVR are expected to live an average of 1.25 years more compared with those undergoing TAVIs, with a mean gain of 1.14 quality-adjusted life-years. Both in-hospital and long-term costs were lower for SU-AVR than for TAVIs with total savings ranging from $4,158 (France) to $20,930 (US).

CONCLUSION

SU-AVR results dominant when compared to TAVIs in intermediate- to high-risk patients. Both in-hospital and long-term costs are lower for SU-AVR than for TAVI patients, with concomitant significant gains in life expectancy, both raw and adjusted for the quality of life.

Appraisal of key trials in aortic and mitral fields

Aortic stenosis and mitral regurgitation are increasingly treated by percutaneous interventions including transcatheter aortic valve implantation (TAVI) and several mitral valve repair techniques, changing the landscape of valvular therapies in which surgery was predominant. Several randomised studies on TAVI have led to the use of this procedure in patients at intermediate or higher operative risk and have set strong foundations for future trials aiming to expand indications or to overcome several residual issues with TAVI. On the other hand, randomised evidence for percutaneous mitral valve repair (PMVR) techniques is still limited, supporting restricted indications to patients with high surgical risk when medical therapy fails. However, in the mitral field, several ongoing trials comparing PMVR with medical therapy or surgery will help to define optimal mitral regurgitation management in this era of evolving catheter-based treatment options. The present review will summarise randomised trials comparing TAVI or PMVR with medical therapy or surgery across the risk spectrum which have set the basis for guideline recommendations and for clinical use of transcatheter interventions. Characteristics, results, implications, unresolved issues and cost-effectiveness analysis of those trials, grouped according to the surgical risk of enrolled patients, will be appraised.