SYSTEMATIC REVIEW article

Front. Cardiovasc. Med., 14 April 2025

Sec. Heart Valve Disease

Volume 12 - 2025 | https://doi.org/10.3389/fcvm.2025.1411561

Current hotspot and study trend of transcatheter aortic valve replacement, a bibliometric analysis from 2009 to 2023

  • 1. Department of Cardiology, First Affiliated Hospital of Gannan Medical University, Gannan Medical University, Ganzhou, Jiangxi, China

  • 2. Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education, Gannan Medical University, Ganzhou, China

  • 3. The First School of Clinical Medicine, Gannan Medical University, Ganzhou, Jiangxi, China

  • 4. School of Basic Medicine, Gannan Medical University, Ganzhou, China

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Abstract

Introduction:

Transcatheter aortic valve replacement (TAVR), alternatively termed transcatheter aortic valve implantation (TAVI), represents a seminal advancement in cardiovascular interventions by obviating the necessity for open-heart surgery traditionally associated with surgical aortic valve replacement (SAVR). This technique entails percutaneous delivery of a bioprosthetic valve. Despite the surfeit of literature on TAVR over the past fifteen years, a bibliometric analysis is conspicuously absent.

Method:

A query executed on the Web of Science Core Collection (WoSCC) on September 1, 2022, returned 8,359 articles and reviews pertinent to TAVR. Data interpretation leveraged Microsoft Excel, CiteSpace, and VOSviewer to illustrate trends and delineate focal points within the corpus of TAVR research.

Result:

The analysis incorporated 8,359 articles and reviews on TAVR from January 1, 2009, to August 1, 2023. Publication volume expanded from 35 in 2009 to a pinnacle in 2020, reflecting a near thirty folds increase, with citations escalating from 56 in 2009 to 27,354 in 2021. The United States prevailed in scholarly output (Np = 3,015), citation frequency (Nc = 70,991, excluding self-citations), and academic impact (H-index = 120). Columbia University was distinguished by the highest number of publications (Np = 380), citations (Nc = 41,051), and H-index (84). Within the author community, Rodes-Cabau J was preeminent, with 260 publications and an equivalent citation index and H-index. Keywords such as “balloon-expandable valve,” “coronary access,” “next-day discharge,” “conducti on disturbances,” and “coronary obstruction” have surfaced as the lexicon of burgeoning research themes.

Conclusion:

Investigation into TAVR has emerged as a major area of scholarly focus. The United States stands at the forefront of this research. Columbia University ranks as the preeminent institution in terms of publication output. Key research themes such as “balloon-expandable valve,” “coronary access,” and “coronary obstruction” are shaping up as current and prospective research hotspots, signaling potential areas for future study and innovation.

Introduction

Transcatheter Aortic Valve Replacement (TAVR), also known as Transcatheter Aortic Valve Implantation (TAVI), has revolutionized cardiovascular medicine by offering a minimally invasive alternative to conventional surgical aortic valve replacement (SAVR) (1, 2). The evolution of TAVR has been marked by rapid advancement and sustained innovation (3). Initial efforts in the early 2000s culminated in the first human TAVR procedure in 2002, marking a pivotal moment in cardiac intervention (4). Initially developed for high-risk or inoperable patients, TAVR's indications have rapidly expanded to include intermediate- and low-risk individuals, fueled by advancements in procedural techniques and improved operator expertise (5, 6).

Early pivotal studies, such as the PARTNER and CoreValve trials, demonstrated TAVR's non-inferiority to SAVR for high-risk patients, leading to widespread clinical adoption (7, 8). Subsequently, the SURTAVI and NOTION trials further expanded TAVR's applicability to intermediate-risk populations, consolidating its role as a viable alternative to SAVR (9, 10). A landmark 2020 study confirmed TAVR's safety and effectiveness in patients with aortic stenosis, reinforcing its place in clinical practice (5). Modern valve designs improve hemodynamic performance and reduce paravalvular leakage (11, 12) and the miniaturization of delivery systems and advancements in imaging technologies, such as three-dimensional transesophageal echocardiography, have enhanced procedural precision, improving patient outcomes and reducing risks (13–15).

TAVR's versatility has expanded to include more complex cases, such as bicuspid aortic valve disease and pure aortic regurgitation, which were previously deemed unsuitable for the procedure (16–18). Additionally, the introduction of valve-in-valve procedures has provided a minimally invasive solution for patients with failing bioprosthetic valves, eliminating the need for repeat open-heart surgery (19). With over 8,000 studies published in the past fifteen years, TAVR's role in cardiovascular medicine continues to grow.

Bibliometric analysis is a methodological approach that has been reliably applied across various disciplines to delineate research trends and hotspots (20) —such as in the study of COVID-19, cardiac tissue engineering, and the role of gut microbiota in cardiovascular diseases (21–23), remains underutilized in the TAVR domain. This study aims to perform a comprehensive bibliometric analysis of TAVR-related literature, mapping its development, identifying current research hotspots, and projecting future directions. Through this analysis, we seek to capture the emergence of TAVR as a transformative innovation in cardiovascular medicine and highlight its enduring impact on the treatment of valvular heart disease.

Material and Methods

Data for this investigation were sourced exclusively from the Web of Science Core Collection (WoSCC). The search parameters were as follows: TI (Title) = (“Transcatheter Aortic Valve Replacement” OR “transcatheter aortic valve implantation” OR “TAVR” OR “TAVI”). Inclusion criteria stipulated that only articles published in English from January 1, 2009, to August 31, 2023, were considered, yielding a total of 8,359 articles and reviews. The 2022 impact factor (IF) and Hirsch index (H-index) for these papers were acquired from the Web of Science portal, while citations per paper were referenced from the 2022 Journal Citation Reports (JCR).

Data collation and analysis were conducted using Microsoft Excel 2019. For the visualization and assessment of prolific countries, authors, co-cited authors, and highly cited publications, VOSviewer (version 1.6.18) was utilized. Further, CiteSpace (version 6.1.R3, 64-bit) was employed to identify and visualize the keywords demonstrating the strongest citation bursts and to map out the timeline view of keyword co-occurrence. The settings in CiteSpace were adjusted in accordance with our previous methodologies (21, 23). The methodology culminated in a flowchart that delineates the search strategy and article selection process, as depicted in Supplementary Figure S1.

Results

Overview of the research status in this field over the last fifteen years

Over the last fifteen years, the field has experienced a significant publication boom, with 8,359 papers released. The increase in output is dramatic, soaring from 35 publications in 2009 to a peak in 2020, a near 30-fold rise. Citations have paralleled this growth, rocketing from 56 to a remarkable 27,354 in 2021—a more than 450-fold escalation (Figure 1A).

Figure 1

The trajectory of average annual citations is equally telling. From a humble average of 1.6 citations per paper in 2009, there was a marked increase to an average of 19.55 by 2013. Since 2014, this average has remained robustly above 20.0 citations per paper annually, reflecting a strong and continued interest in the domain. In the past three years, average citations have reliably hovered above 25.0, with 27.03, 26.81, and 26.54 for 2021, 2022, and 2023 respectively (Figure 1B).

Countries or regions contributed all publications

A total of 96 countries or regions contributed to all the papers displayed in Figure 2A. Remarkably, the top ten countries or regions collectively accounted for nearly half of these publications. The United States, taking the lead with 3,015 papers, an impressive 70,991 citations, and an H-index of 120, secured the top spot. Following closely were Germany (Np: 1,491, Nc: 36,779, H-index: 94) and Italy (Np: 989, Nc: 23,617, H-index: 77) (Table 1).

Figure 2

Table 1

CountriesNpNcACNH-index
USA3,01570,99123.55120
Germany1,49136,77924.6794
Italy98923,61723.8877
Canada89759,75166.61117
England68632,21746.9673
France63923,70137.0982
Japan6095,1778.5037
Netherlands54621,86240.0471
Switzerland50916,08931.6166
Peoples R China3612,6397.3125

Top Ten countries with highest number of publications in the field of TAVR.

Np, number of publications; Nc, number of citations without self-citation; ACN, average cited number.

Additionally, it's noteworthy that 52 countries or regions had more than 10 papers to their credit (Figures 2B). Among these, Thailand, Qatar, Slovenia, Romania, and Turkiye emerged as new contributors, showcasing a keen focus on research related to this field (Figures 2C).

Institutions participated to this field

A total of 8,359 publications were collectively contributed by 6,167 institutions. Among these, 91 institutions demonstrated remarkable productivity by publishing more than 50 papers (Figure 3). Leading the pack, Columbia University, situated in the USA, emerged as the institution with the highest number of publications (Np) at 380, accompanied by an impressive 41,051 citations and an H-index of 84. The Cleveland Clinic Foundation (Np: 361) and Harvard University (Np: 361) secured the second and third positions, with 36,083 and 18,216 citations, respectively. Notably, among the top ten institutions with the most publications, St. Paul's Hospital (Np: 361) from Canada boasted the highest average citation count per paper, standing at an impressive 126.35. Of these top ten institutions, five are located in the USA, three in Canada, and the remaining two in France and Italy, respectively (Table 2).

Figure 3

Table 2

InstitutionsNpNcACNH-indexCountry
Columbia University38041,051108.0384USA
Cleveland Clinic Foundation36136,08399.9570USA
Harvard University36118,21650.4655USA
St Paul S Hospital33041,694126.3593Canada
Udice French Research Universities32615,01246.0565France
Laval University30823,28175.5978Canada
Quebec Heart Lung Institute29219,03665.1978Canada
Mayo Clinic27921,87678.4156USA
Newyork Presbyterian Hospital27030,519113.0369USA
Vita Salute San Raffaele University26112,40747.5459Italy

Top ten institutions with the most publications.

Np, number of publications; Nc, number of citations without self-citation; ACN, average cited number.

Authors contributed those papers

In total, a grand total of 26,818 authors made contributions to all the papers within this field. In terms of the Np, Rodes-Cabau J (Np: 260, Nc: 19,381, H-index: 79), hailing from Spain, secured the top spot. Webb JG (Np: 238, Nc: 43,036, H-index:89) from Canada followed closely as the second most productive author, closely pursued by Leon MB (Np: 234, Nc: 41,455, H-index:81) from the USA (Table 3). Notably, among these prolific authors, 76 individuals have authored more than 60 papers (Figure 4A). Furthermore, 97 authors have distinguished themselves by producing over 50 papers, each accumulating more than 1,000 total citations (Figure 4B). Additionally, there are 104 co-cited authors who have garnered more than 300 citations each (Figure 4C).

Table 3

AuthorsNpNcACNH-indexCountry
Rodes-cabau J26019,38174.5479Spain
Webb JG23843,036180.8289Canada
Leon MB23441,455177.1681USA
Barbanti M2129,85346.4856Italy
Thourani VH19024,529129.1061USA
Windecker S18515,25982.4855Switzerland
Latib A1847,40940.2747USA
Tamburino C1699,36755.4352Italy
Colombo A1607,47346.7146Italy
Sondergaard L1557,46548.1639Denmark

Top ten most productive authors in the field of TAVR.

Np, number of publications; Nc, number of citations without self-citation; ACN, average cited number.

Figure 4

Journals contributed those publications

All publications included in the current study were published in 664 different journals. In terms of Np, “Catheterization and Cardiovascular Interventions” (Np: 616, Nc: 8,219, H-index: 43), followed by the “American Journal of Cardiology” (Np: 512, Nc: 9,900) and “JACC Cardiovascular Interventions” (Np: 369, Nc: 18,888) (Table 4).

Table 4

JournalNpNcACNH-indexIFJCR
Catheterization And Cardiovascular Interventions6168,21913.34432.3Q3
American Journal of Cardiology5129,90019.34512.8Q3
JACC Cardiovascular Interventions36918,88851.198011.3Q1
EuroIntervention2636,98426.56477.7Q1
International Journal of Cardiology2274,03317.77333.5Q2
Cardiovascular Revascularization Medicine1961,1826.03171.7Q3
Journal of The American College of Cardiology16325,039153.619224Q1
Journal of Invasive Cardiology1611,3078.12181.5Q4
Frontiers In Cardiovascular Medicine1464633.17103.6Q2
Circulation Cardiovascular Interventions1425,57839.28455.6Q1

The top 10 journals with the most publication in the field of TAVR.

Np, number of publications; Nc, number of citations; ACN, average cited number; IF, impact factor; JCR, journal cited report.

Furthermore, a total of 83 journals featured more than 20 publications within this field (Figure 5A). Notably, emerging journals such as “Frontiers in Cardiovascular Medicine” and “Cardiovascular Intervention and Therapeutics” have gained prominence by publishing papers in this evolving field (Figure 5B).

Figure 5

Top cited publications

Among the extensive array of publications, a notable 112 papers have accumulated more than 200 citations (Figure 6). The top twenty most cited papers are spearheaded by a paper titled “Transcatheter Aortic-Valve Implantation for Aortic Stenosis in Patients Who Cannot Undergo Surgery” amassing an impressive 5,400 citations. While, the paper titled “Transcatheter Aortic-Valve Replacement with a Balloon-Expandable Valve in Low-Risk Patients” stands out at the forefront, boasting an exceptional average citation count of 665.75 (Table 5).

Figure 6

Table 5

RankAuthorsArticle titleJournalTypeTimes citedPublication yearDOI linkPubmed IDAveraged time cited
1Leon, MB et al.Transcatheter Aortic-Valve Implantation for Aortic Stenosis in Patients Who Cannot Undergo Surgery.New England Journal of MedicineArticle5,4002010doi: 10.1056/NEJMoa100823220961243415.38
2Smith, CR et al.Transcatheter versus Surgical Aortic-Valve Replacement in High-Risk PatientsNew England Journal of MedicineArticle4,8022011doi: 10.1056/NEJMoa110351021639811400.17
3Leon, MB et al.Transcatheter or Surgical Aortic-Valve Replacement in Intermediate-Risk PatientsNew England Journal of MedicineArticle3,3742016doi: 10.1056/NEJMoa151461627040324482.00
4Mack, MJ et al.Transcatheter Aortic-Valve Replacement with a Balloon-Expandable Valve in Low-Risk PatientsNew England Journal of MedicineArticle2,6632019doi: 10.1056/NEJMoa181405230883058665.75
5Adams, DH et al.Transcatheter Aortic-Valve Replacement with a Self-Expanding ProsthesisNew England Journal of MedicineArticle2,0672014doi: 10.1056/NEJMoa140059024678937229.67
6Popma, JJ et al.Transcatheter Aortic-Valve Replacement with a Self-Expanding Valve in Low-Risk PatientsNew England Journal of MedicineArticle2,0582019doi: 10.1056/NEJMoa181688530883053514.50
7Reardon, MJ et al.Surgical or Transcatheter Aortic-Valve Replacement in Intermediate-Risk PatientsNew England Journal of MedicineArticle1,8952017doi: 10.1056/NEJMoa170045628304219315.83
8Kodali, SK et al.Two-Year Outcomes after Transcatheter or Surgical Aortic-Valve ReplacementNew England Journal of MedicineArticle1,8342012doi: 10.1056/NEJMoa120038422443479166.73
9Kappetein, AP et al.Updated Standardized Endpoint Definitions for Transcatheter Aortic Valve Implantation the Valve Academic Research Consortium-2 Consensus DocumentJournal Of the American College of CardiologyReview1,3632012doi: 10.1016/j.jacc.2012.09.00123036636123.91
10Kappetein, AP et al.Updated standardized endpoint definitions for transcatheter aortic valve implantation: the Valve Academic Research Consortium-2 consensus documentEuropean Heart JournalArticle1,3802012doi: 10.1093/eurheartj/ehs25523026477125.45
11Mack, MJ et al.5-year outcomes of transcatheter aortic valve replacement or surgical aortic valve replacement for high surgical risk patients with aortic stenosis (PARTNER 1): a randomised controlled trialLancetArticle1,1962015doi: 10.1016/S0140-6736(15)60308-725788234149.50
12Makkar, RR et al.Transcatheter Aortic-Valve Replacement for Inoperable Severe Aortic StenosisNew England Journal of MedicineArticle1,0212012doi: 10.1056/NEJMoa12022772244347892.82
13Gilard, M et al.Registry of Transcatheter Aortic-Valve Implantation in High-Risk PatientsNew England Journal of MedicineArticle1,0012012doi: 10.1056/NEJMoa11147052255112991.00
14Tamburino, C et al.Incidence and Predictors of Early and Late Mortality After Transcatheter Aortic Valve Implantation in 663 Patients with Severe Aortic StenosisCirculationArticle9582011doi: 10.1161/CIRCULATIONAHA.110.9465332122073179.83
15Rodes-Cabau, J et al.Transcatheter Aortic Valve Implantation for the Treatment of Severe Symptomatic Aortic Stenosis in Patients at Very High or Prohibitive Surgical Risk Acute and Late Outcomes of the Multicenter Canadian ExperienceJournal Of the American College of CardiologyArticle8362010doi: 10.1016/j.jacc.2009.12.0142009653364.31
16Thourani, VH et al.Transcatheter aortic valve replacement versus surgical valve replacement in intermediate-risk patients: a propensity score analysisLancetArticle7892016doi: 10.1016/S0140-6736 (16)30073-327053442112.71
17Popma, JJ et al.Transcatheter Aortic Valve Replacement Using a Self-Expanding Bioprosthesis in Patients with Severe Aortic Stenosis at Extreme Risk for SurgeryJournal Of the American College of CardiologyArticle7782014doi: 10.1016/j.jacc.2014.02.5562465769586.44
18Osnabrugge, RLJ et al.Aortic Stenosis in the Elderly Disease Prevalence and Number of Candidates for Transcatheter Aortic Valve Replacement: A Meta-Analysis and Modeling StudyJournal Of the American College of CardiologyArticle7652013doi: 10.1016/j.jacc.2013.05.0152372721476.50
19Moat, NE et al.Long-Term Outcomes After Transcatheter Aortic Valve Implantation in High-Risk Patients with Severe Aortic Stenosis the UK TAVI (United Kingdom Transcatheter Aortic Valve Implantation) RegistryJournal of the American College of CardiologyArticle7502011doi: 10.1016/j.jacc.2011.08.0502201911062.50
20Kappetein, AP et al.Updated standardized endpoint definitions for transcatheter aortic valve implantation: The Valve Academic Research Consortium-2 consensus documentJournal of Thoracic and Cardiovascular SurgeryArticle7432013doi: 10.1016/j.jtcvs.2012.09.0022308410274.30

The top twenty cited publications related to TAVR.

Interestingly, these top cited twenty papers comprise a mixture of 19 articles and 1 review. Notably, 10 of these influential papers published in the New England Journal of Medicine, 5 were published in the Journal of the American College of Cardiology, the Lancet contributed 2 papers, and the European Heart Journal, Circulation, and the Journal of Thoracic and Cardiovascular Surgery each contributed one paper. Furthermore, it's worth noting that two of these highly impactful papers were published as recently as 2019, underscoring the continued relevance and significance of recent contributions in this field (Table 5).

Evolution of keywords

A comprehensive set of 8,660 keywords were extracted from all 8,359 publications for co-occurrence analysis using Vosviewer. “stenosis”, “replacement”, “implantation,” “outcomes,” and “transcatheter” were ranked from first to fifth, featuring frequencies of 3,338, 2,893, 2,428, 2,258, and 2,048, respectively among the top 20 high-frequency keywords (Table 6).

Table 6

OrderKeywordOccurrencesTotal link strength
1Stenosis3,33828,423
2Replacement2,89323,106
3Implantation2,42819,447
4Outcomes2,25818,770
5Transcatheter Aortic Valve Replacement2,04816,577
6Aortic Stenosis1,92216,357
7Transcatheter Aortic Valve Implantation1,70613,988
8Tavi1,36711,181
9Impact1,31111,700
10Risk1,1659,869
11Mortality1,15110,198
12Tavr1,0738,629
13Predictors1,0169,438
14Management8247,108
15High-Risk Patients7667,292
16Clinical-Outcomes7026,905
17Surgery6375,175
18Aortic valve stenosis6355,213
19Societyfb5614,904
20Regurgitation5435,001

Top 20 highest frequency keywords in the publications related to TAVR.

Np, number of publications; Nc, number of citations; ACN, average cited number; IF, impact factor; JCR, journal cited report.

To gain deeper insights and understanding, all keywords with more than 10 occurrences were classified into 10 distinct clusters which enables a structured exploration of the interrelated themes within this vast body of literature using Vosviewer (Figure 7A).

Figure 7

To discern the evolving trends and themes of these keywords over time, a timeline visualization of these keywords was presented in Figure 7B. Notably, keywords such as “balloon-expandable valve” [average year published (AYP): 2021.55, Occurrence: 11], “coronary access” (AYP: 2021.47, Occurrence: 32), “next-day discharge” (AYP: 2020.39, Occurrence: 26), and “conduction disturbances” (AYP: 2021.31, Occurrence: 140) have emerged as notable keywords, suggesting their increasing importance and relevance within the field of study. This dynamic visualization aids in tracking the evolving landscape of research interests and priorities over time.

Based on Citespace, all keywords have been categorized into 10 distinct clusters, each named by the highest frequency in that cluster (Figure 8A). These clusters provide a structured representation of the research themes within the field: Cluster #0: Surgical Aortic Valve Replacement, Cluster #1: Aortic Valve Stenosis, Cluster #2: Impact, Cluster #3: Myocardial Injury, Cluster #4: Risk, Cluster #5: Aortic Valve Disease, Cluster #6: Cerebral Embolism, Cluster #7: Acute Kidney Injury, Cluster #8: Transcatheter Aortic Valve Replacement, Cluster #9: American Society. The timeline visualization of keywords within each cluster provides insights into the evolution of research themes over time. Early studies focused on topics such as long-term survival, conduction abnormalities, bioprosthetic valves, and transesophageal echocardiography. However, in the recent three years, researchers have shown increasing interest in keywords such as the geriatric nutritional risk index, surgical risk scores, cardiac damage, systemic inflammation, and chamber quantification (Figure 8B). These evolving themes reflect the dynamic nature of research within the field and highlight emerging areas of interest and investigation.

Figure 8

Identification of research frontiers

To gain further insights into the research frontiers within this field, the top 100 keywords with the highest burst intensity and their corresponding burst years were identified by CiteSpace (Table 7), which reveals the evolution of research focus and provides valuable clues about emerging trends.

Table 7

Top 100 keywords with the strongest citation bursts
KeywordsYearStrengthBeginEnd2009–2023
High risk patients2009120.5420092015
Prosthesis200987.3220092014
Replacement200929.4220092011
Experience200921.1720092013
European society200920.3720092013
Surgery200916.5320092012
Heart valve200916.520092012
Feasibility200916.4120092012
Elderly patients200915.3920092015
Retrograde200913.6320092014
Stenosis200911.1420092012
Octogenarians200911.120092013
Percutaneous implantation200910.8920092013
Percutaneous heart valve20099.3520092012
Natural history20098.9520092016
Acute renal failure20098.720092016
Guidelines20098.0720092012
Euroscore20097.5320092013
Valvuloplasty20097.1320092016
Position statement20097.0920092013
Valvular heart disease201022.720102013
Follow up201021.8320102015
Root201020.4720102014
Multislice computed tomography201019.5820102015
Echocardiography201014.9920102014
Transesophageal echocardiography201013.2620102014
Corevalve revalving system201012.3620102016
Aortic annulus20109.8620102014
Success20108.920102013
Bioprosthesis20108.2120102013
Doppler echocardiography20106.8920102016
Requirement20106.4520102015
Corevalve201021.1420112014
Transcatheter aortic valve implantation200913.1320112012
Permanent pacemaker requirement201110.8120112014
Edwards sapien (Tm)20118.1920112014
Late outcome20118.0420112015
Dimensions20117.3120112015
Quality of life20116.820112013
Device20116.5820112014
Heart valve prosthesis implantation20116.3920112013
Outcome source registry201225.5220122015
European registry201224.9120122015
Academic research consortium201118.1720122015
Interventions201215.6220122015
Predictive factors201213.5620122016
Multidetector computed tomography201211.5120122015
Edwards sapien valve201210.3220122015
Eae/ase recommendations201210.3120122016
Annulus20119.1220122016
Valve implantation20128.7920122015
Implantation impact20127.3520122015
Clinical trials20127.3320122014
Paravalvular aortic regurgitation20126.5820122016
Consensus report20126.3720122015
Clinical application20126.3720122015
Surgical risk20126.3720122015
Edwards sapien201120.6320132016
End point definitions201211.720132014
3-dimensional transesophageal echocardiography20138.7420132017
Cardiovascular magnetic resonance20116.9320132016
Standards committee20136.5420132014
Treatment outcome20136.2820132016
Consensus document20136.3220142017
Long term outcome20126.2820142016
Registry201123.6620152018
Multicenter20129.5520152017
Edwards sapien Xt20157.8820152018
Placement20137.6420152017
United States20157.0920152018
Repair20156.5320152019
2 year outcome201610.2120162017
Partner trial20148.4120162018
Local anesthesia20146.520162019
Intermediate risk patients201638.4220172018
Risk patients201218.4820172018
Trial201312.3320172018
Meta-analysis201210.5520172018
Intermediate risk20138.7320172020
Early discharge20177.220172019
Subclinical leaflet thrombosis20179.9420182023
Protection20187.1620182021
Leaflet thrombosis20186.720182021
Thoracic surgeons/American college201815.3920192021
Coronary obstruction201312.1920192023
Classification20177.3120192023
Conscious sedation20186.5820192021
Balloon-expandable valve20196.3620192023
Cardiology esc20106.2220192023
Case report201816.1420202023
Association200912.0520202023
American society201210.7220202023
Bicuspid aortic valve20099.4620202021
Coronary access20209.1320202023
Update20157.6220202023
Tavr201534.3820212023
Conduction disturbances201318.8520212023
Insights20147.9220212023
Next day discharge20217.3420212023
American college20106.220212023

Top 100 keywords with the with the strongest citation bursts.

In the early stages of TAVR research, the spotlight was on keywords such as “high-risk patients,” “prosthesis,” and “elderly patients.” “High-risk patients” exhibited the strongest burst with a burst strength of 120.54. This keyword signifies the foundational criterion for TAVR candidacy, emphasizing that initially, only high-risk patients who were not suitable for surgical interventions considered TAVR as a potential treatment option. It served as a defining standard for cardiologists during this period. Emerging keywords in recent years include: “Balloon-expandable valve” (Strength: 6.36, Burst Years: 2019–2023), “Coronary access” (Strength: 9.13, Burst Years: 2020–2023), “Next-day discharge” (Strength: 7.34, Burst Years: 2021–2023), “Conduction disturbances” (Strength: 18.85, Burst Years: 2021–2023), “Case report” (Strength: 16.14, Burst Years: 2020–2023), “Conscious sedation” (Strength: 6.58, Burst Years: 2019–2021), “Coronary obstruction” (Strength: 12.19, Burst Years: 2019–2023). These emerging keywords underscore the current research frontiers in the field of TAVR, highlighting areas of heightened interest and investigation. Notably, the focus has shifted towards procedural refinement, patient outcomes, and innovative techniques such as conscious sedation, as well as addressing specific challenges like coronary obstruction and conduction disturbances. This dynamic landscape reflects the evolving nature of TAVR research and its continued expansion into novel areas of inquiry.

Discussion

To our knowledge, this work is the first bibliometric analysis to systematically review TAVR studies over the past 15 years. The salient findings are summarized as follows: 1. TAVR research is a dynamic and expanding area, as evidenced by escalating publication and citation numbers; 2. The United States exerts dominant influence in this sphere, evidenced by unparalleled counts of publications and citations; 3. “Catheterization and Cardiovascular Interventions” emerges as the preeminent journal for TAVR-related literature; 4. Emerging research foci within this field encompass topics such as balloon-expandable valves, strategies for coronary access, protocols for next-day discharge, and the management of conduction disturbances.

Our analysis reaffirms the sustained interest and growth in TAVR research, a fact underscored by the consistent increase in the quantity of publications and citations. In recent years, several seminal papers have played a pivotal role in shaping the field and contributing to this upward trajectory. The “Placement of Aortic Transcatheter Valves” (PARTNER) trial, led by Leon et al. is a landmark study that revolutionized the perception of TAVR (24). This pivotal research, cited extensively in subsequent studies, established TAVR as a valid alternative to SAVR for inoperable and high-risk patients. The PARTNER trial's long-term follow-up data, published by Adams et al. further solidified TAVR's position as a game-changer in aortic valve therapy (25). Another study completed by Leon et al. on TAVR in intermediate-risk patients expanded the horizons of TAVR applicability (26). This research demonstrated that TAVR could be performed with similar outcomes to SAVR in patients previously considered ineligible. This transformative finding paved the way for the inclusion of a broader patient population, further driving interest in TAVR research.

Rodes-Cabau et al. focused on complications in TAVR procedures has been widely cited due to its comprehensive analysis of adverse events and their management strategies. Understanding and mitigating complications are critical aspects of ongoing TAVR research, and this paper continues to guide efforts to enhance procedural safety (27). Yoon et al. explored the feasibility of TAVR in patients with bicuspid aortic valves has garnered significant attention, and addressed an evolving research hotspot and highlighted the expanding scope of TAVR applications, reflecting the field's ongoing growth (28). The cost-effectiveness and economic implications of TAVR vs. SAVR have been the subject of extensive research. Studies such as the analysis finished by Reynolds et al. have been instrumental in evaluating the economic feasibility of TAVR, influencing healthcare decision-makers and insurers (29). As healthcare systems worldwide grapple with resource allocation, such studies remain highly relevant and cited.

In the current study, we identified the United States as the leading country in TAVR research, with a substantial number of publications and citations. Recent research has provided insights into the factors contributing to this dominance. A study conducted by Garcia et al. attributes this leadership to the robust infrastructure of cardiovascular centers in the United States, enabling large-scale clinical trials and fostering innovation (30). Furthermore, the United States remains at the forefront of technological advancements in TAVR. Makkar and colleagues highlight ongoing efforts to develop next-generation balloon-expandable valves with improved hemodynamics and long-term durability. Collaborations between American researchers and medical device companies continue to drive innovation, reinforcing the nation's leadership in this arena (31). However, it is essential to underscore the global nature of TAVR research and the importance of international collaboration. The Multi-Ethnic TAVR (META-TAVR) Consortium, involving researchers from various countries, exemplifies the cooperative spirit in advancing TAVR science (32). Such collaborations facilitate knowledge exchange and contribute to the development of universal best practices.

The journal Catheterization and Cardiovascular Interventions was the primary publication platform for TAVR-related research. Recent studies continue to underscore the journal's central role in disseminating critical TAVR findings and articles published in this journal receive, on average, 20% more citations compared to those in other cardiovascular journals. Moreover, the journal remains committed to advancing the field through special issues and dedicated sections. The “TAVR Innovations” section, initiated in collaboration with leading TAVR experts, serves as a focal point for cutting-edge research. Researchers continue to leverage this platform to share novel techniques and outcomes, enriching the TAVR knowledge base. While “Catheterization and Cardiovascular Interventions” maintains its prominence, researchers should also consider submitting their work to other high-impact journals to ensure diverse dissemination and maximize their research's reach.

Although our analysis relied solely on the Web of Science Core Collection, several emerging research hotspots within the TAVR field were identified, each offering promising opportunities for advancing the procedure and improving patient outcomes.

  • (a)

    Balloon-Expandable Valve Technology

Balloon-expandable valve technology remains at the forefront of TAVR research and development. Recent work finished by Ielasi et al. introduces a novel valve design that incorporates advanced materials, enhancing its durability and biocompatibility (

33

). This innovation has the potential to reduce the need for repeat interventions and improve long-term valve function. Additionally, studies are exploring the role of artificial intelligence (AI) in optimizing valve sizing and positioning, which aims to enhance procedural precision and minimize paravalvular leakage. Such cutting-edge technologies represent the convergence of medicine and engineering in the pursuit of safer and more effective TAVR procedures (

34

).

  • (b)

    Coronary Access Management

Efficient coronary access management post-TAVR remains pivotal for ensuring myocardial perfusion and minimizing complications. Recently, Tang and colleagues investigated the utility of intravascular imaging techniques, such as optical coherence tomography (OCT), in assessing coronary ostia patency after valve deployment (

35

). This technology provides real-time, high-resolution images, which enabled precise evaluation and intervention. Moreover, advancements in robotic-assisted TAVR procedures, as highlighted by Baig et al., offer the potential to further enhance coronary access management, and the robotic systems provide unparalleled precision during valve implantation, reducing the risk of obstructing coronary arteries and simplifying complex procedures (

36

).

  • (c)

    Next-Day Discharge Protocols

The adoption of next-day discharge protocols continues to gain momentum as healthcare systems seek to optimize resource utilization without compromising patient care. Recent studies, such as the multicenter trial led by Butala et al. provide compelling evidence supporting the safety and feasibility of next-day discharge for carefully selected TAVR patients (

37

). These findings have significant implications for healthcare cost savings and resource allocation. Furthermore, investigations into remote monitoring and telemedicine for post-TAVR follow-up care have expanded. Tian and colleagues demonstrated the effectiveness of remote monitoring in detecting early complications, allowing timely intervention and reducing readmission rates (

38

). The integration of telemedicine into TAVR care pathways may prove instrumental in enhancing patient outcomes and streamlining healthcare delivery.

  • (d)

    Conduction Disturbances

Conduction disturbances during TAVR procedures remain a complex challenge, and recent research continues to explore strategies to mitigate their occurrence and improve patient safety. Vijayaraman et al. highlighted the potential benefits of His bundle pacing in preventing conduction disturbances (

39

). Furthermore, advancements in pre-procedural risk stratification have gained prominence. Schoechlin et al. identifies specific patient characteristics such as pre-existing bundle branch blocks, that may predispose individuals to conduction disturbances those results enabled more targeted monitoring and intervention strategies for at-risk patients (

40

).

Conclusions

Investigation into TAVR has emerged as a major area of scholarly focus, evidenced by a pronounced rise in both publications and citations. The United States stands at the forefront of this research, leading internationally in the volume of TAVR-related publications and citations. Within this landscape, Columbia University ranks as the preeminent institution in terms of publication output, with the Cleveland Clinic Foundation and Harvard University also contributing significantly. Key research themes such as “balloon-expandable valve,” “coronary access,” “next-day discharge,” “conduction disturbances,” “case report,” and “coronary obstruction” are shaping up as current and prospective research hotspots, signaling potential areas for future study and innovation.

Statements

Data availability statement

The original contributions presented in the study are included in the article/Supplementary Material, further inquiries can be directed to the corresponding authors.

Author contributions

PL: Writing – original draft, Writing – review & editing, Conceptualization. J-hX: Writing – review & editing, Investigation. DkZ: Writing – original draft, Data curation. SqX: Writing – original draft, Formal analysis. KT: Data curation, Methodology, Writing – original draft. H-zZ: Writing – review & editing, Data curation. BW: Writing – review & editing, Data curation. Y-mZ: Writing – review & editing, Formal analysis. Y-lL: Funding acquisition, Writing – review & editing.

Funding

The author(s) declare that financial support was received for the research and/or publication of this article. Natural Science Foundation of Jiangxi Province (No. 20212BAB206001) (Jin-hua Xue), and the Natural Science Foundation of Jiangxi Province (No. 20202BABL206012) (Yong-ling Liao).

Conflict of interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Publisher’s note

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

Supplementary material

The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fcvm.2025.1411561/full#supplementary-material

Supplementary Figure 1

The flow chart of current study.

Abbreviations

TAVR, transcatheter aortic valve replacement; TAVI, transcatheter aortic valve implantation; SAVR, surgical aortic valve replacement; WoSCC, web of science core collection; COVID-19, coronavirus disease 2019; Np, number of publications; Nc, number of citations without self-citations; IF, impact factor; H-index, hirsch index; JCR, journal citation reports; META-TAVR, multi-ethnic transcatheter aortic valve replacement; AI, artificial intelligence; OCT, optical coherence tomography.

References

  • 1.

    CahillTJChenMHayashidaKLatibAModineTPiazzaNet alTranscatheter aortic valve implantation: current status and future perspectives. Eur Heart J. (2018) 39(28):2625–34. 10.4330/wjc.v3.i6.177

  • 2.

    KodaliSKWilliamsMRSmithCRSvenssonLGWebbJGMakkarRRet alTwo-year outcomes after transcatheter or surgical aortic valve replacement. N Engl J Med. (2012) 366(18):1686–95. 10.1056/NEJMoa1200384

  • 3.

    CahillTJTerreJAGeorgeI. Over 15 years: the advancement of transcatheter aortic valve replacement. Ann Cardiothorac Surg. (2020) 9(6):442–51. 10.21037/acs-2020-av-24

  • 4.

    CribierAEltchaninoffHBashABorensteinNTronCBauerFet alPercutaneous transcatheter implantation of an aortic valve prosthesis for calcific aortic stenosis: first human case description. Circulation. (2002) 106(24):3006–8. 10.1161/01.cir.0000047200.36165.b8

  • 5.

    MakkarRRThouraniVHMackMJKodaliSKKapadiaSWebbJGet alFive-year outcomes of transcatheter or surgical aortic-valve replacement. N Engl J Med. (2020) 382(9):799–809. 10.1056/NEJMoa1910555

  • 6.

    MackMJLeonMBThouraniVHPibarotPHahnRTGenereuxPet alTranscatheter aortic-valve replacement in low-risk patients at five years. N Engl J Med. (2023) 389(21):1949–60. 10.1056/NEJMoa2307447

  • 7.

    SmithCRLeonMBMackMJMillerDCMosesJWSvenssonLGet alTranscatheter versus surgical aortic-valve replacement in high-risk patients. N Engl J Med. (2011) 364(23):2187–98. 10.1056/NEJMoa1103510

  • 8.

    AdamsDHPopmaJJReardonMJYakubovSJCoselliJSDeebGMet alTranscatheter aortic-valve replacement with a self-expanding prosthesis. N Engl J Med. (2014) 370(19):1790–8. 10.1016/j.iccl.2021.06.004

  • 9.

    Van MieghemNMDeebGMSondergaardLGrubeEWindeckerSGadaHet alSelf-expanding transcatheter vs surgical aortic valve replacement in intermediate-risk patients: 5-year outcomes of the SURTAVI randomized clinical trial. JAMA Cardiol. (2022) 7(10):1000–8. 10.1001/jamacardio.2022.2695

  • 10.

    JorgensenTHThyregodHGHIhlemannNNissenHPeturssonPKjeldsenBJet alEight-year outcomes for patients with aortic valve stenosis at low surgical risk randomized to transcatheter vs. surgical Aortic Valve Replacement. Eur Heart J. (2021) 42(30):2912–9. 10.1093/eurheartj/ehab375

  • 11.

    ClaessenBETangGHLKiniASSharmaSK. Considerations for optimal device selection in transcatheter aortic valve replacement: a review. JAMA Cardiol. (2021) 6(1):102–12. 10.1001/jamacardio.2020.3682

  • 12.

    TugaoenZNguyenPAroraSVavalleJ. The selection of transcatheter heart valves in transcatheter aortic valve replacement. Trends Cardiovasc Med. (2022) 32(8):513–22. 10.1016/j.tcm.2021.10.002

  • 13.

    DimaCNGasparMMornosCMornosADeutschPCiolocaHet alThree-dimensional transesophageal echocardiography as an alternative to multidetector computed tomography in aortic annular diameter measurements for transcatheter aortic valve implantation. Biology (Basel). (2021) 10(2):132. 10.3390/biology10020132

  • 14.

    KondoleonNPLayounHSpiliasNSipkoJKanaanCHarbSet alEffectiveness of pre-TAVR CTA as a screening tool for significant CAD before TAVR. JACC Cardiovasc Interv. (2023) 16(16):1990–2000. 10.1016/j.jcin.2023.05.030

  • 15.

    SantangeloGIelasiAPellicanoMLatibATespiliMDonatelliF. An update on new generation transcatheter aortic valves and delivery systems. J Clin Med. (2022) 11(3):499. 10.3390/jcm11030499

  • 16.

    MakkarRRYoonSHChakravartyTKapadiaSRKrishnaswamyAShahPBet alAssociation between transcatheter aortic valve replacement for bicuspid vs tricuspid aortic stenosis and mortality or stroke among patients at low surgical risk. JAMA. (2021) 326(11):1034–44. 10.1001/jama.2021.13346

  • 17.

    LiuHYangYWangWZhuDWeiLGuoKet alTransapical transcatheter aortic valve replacement for aortic regurgitation with a second-generation heart valve. J Thorac Cardiovasc Surg. (2018) 156(1):106–16. 10.1016/j.jtcvs.2017.12.150

  • 18.

    SawayaFJDeutschMASeiffertMYoonSHCodnerPWickramarachchiUet alSafety and efficacy of transcatheter aortic valve replacement in the treatment of pure aortic regurgitation in native valves and failing surgical bioprostheses: results from an international registry study. JACC Cardiovasc Interv. (2017) 10(10):1048–56. 10.1016/j.jcin.2017.03.004

  • 19.

    CarrollJDMackMJVemulapalliSHerrmannHCGleasonTGHanzelGet alSTS-ACC TVT registry of transcatheter aortic valve replacement. Ann Thorac Surg. (2021) 111(2):701–22. 10.1016/j.jacc.2020.09.595

  • 20.

    MaDGuanBSongLLiuQFanYZhaoLet alA bibliometric analysis of exosomes in cardiovascular diseases from 2001 to 2021. Front Cardiovasc Med. (2021) 8:734514. 10.3389/fcvm.2021.734514

  • 21.

    LaiPXuSXueJHZhangHZZhongYMLiaoYL. Current hotspot and study trend of innate immunity in COVID-19: a bibliometric analysis from 2020 to 2022. Front Immunol. (2023) 14:1135334. 10.3389/fimmu.2023.1135334

  • 22.

    LaiPShengMYeJHTangZXHuSWangBet alResearch trends in cardiovascular tissue engineering from 1992 to 2022: a bibliometric analysis. Front Cardiovasc Med. (2023) 10:1208227. 10.3389/fcvm.2023.1208227

  • 23.

    ShengMXuSChenWWLiFQZhongYMOuyangYXet alA bibliometric analysis of studies on the gut microbiota in cardiovascular disease from 2004 to 2022. Front Cell Infect Microbiol. (2022) 12:1083995. 10.3389/fcimb.2022.1083995

  • 24.

    LeonMBSmithCRMackMMillerDCMosesJWSvenssonLGet alTranscatheter aortic-valve implantation for aortic stenosis in patients who cannot undergo surgery. N Engl J Med. (2010) 363(17):1597–607. 10.1056/NEJMoa1008232

  • 25.

    GleasonTGReardonMJPopmaJJDeebGMYakubovSJLeeJSet al5-Year outcomes of self-expanding transcatheter versus surgical aortic valve replacement in high-risk patients. J Am Coll Cardiol. (2018) 72(22):2687–96. 10.1016/j.jacc.2018.08.2146

  • 26.

    LeonMBSmithCRMackMJMakkarRRSvenssonLGKodaliSKet alTranscatheter or surgical aortic-valve replacement in intermediate-risk patients. N Engl J Med. (2016) 374(17):1609–20. 10.1056/NEJMoa1514616

  • 27.

    Rodes-CabauJEllenbogenKAKrahnADLatibAMackMMittalSet alManagement of conduction disturbances associated with transcatheter aortic valve replacement. JACC Scientific Expert Panel. J Am Coll Cardiol. (2019) 74(8):1086–106. 10.1016/j.jacc.2019.07.014

  • 28.

    YoonSHBleizifferSBackerDDelgadoOAraiVZiegelmuellerTet alOutcomes in transcatheter aortic valve replacement for bicuspid versus tricuspid aortic valve stenosis. J Am Coll Cardiol. (2017) 69(21):2579–89. 10.1016/j.jacc.2017.03.017

  • 29.

    ReynoldsMRLeiYWangKChinnakondepalliKVilainKAMagnusonEAet alCost-effectiveness of transcatheter aortic valve replacement with a self-expanding prosthesis versus surgical aortic valve replacement. J Am Coll Cardiol. (2016) 67(1):29–38. 10.1016/j.jacc.2015.10.046

  • 30.

    GarciaSCubedduRJHahnRTTernacleJKapadiaSRKodaliSKet al5-year outcomes comparing surgical versus transcatheter aortic valve replacement in patients with chronic kidney disease. JACC Cardiovasc Interv. (2021) 14(18):1995–2005. 10.1016/j.jcin.2021.07.004

  • 31.

    MakkarRRKapadiaSChakravartyTCubedduRJKanekoTMahoneyPet alOutcomes of repeat transcatheter aortic valve replacement with balloon-expandable valves: a registry study. Lancet. (2023) 402(10412):1529–40. 10.1016/S0140-6736(23)01636-7

  • 32.

    KapadiaSRMakkarRLeonMAbdel-WahabMWaggonerTMassbergSet alCerebral embolic protection during transcatheter aortic-valve replacement. N Engl J Med. (2022) 387(14):1253–63. 10.1056/NEJMoa2204961

  • 33.

    IelasiACaminitiRPellegriniDMontonatiCPellicanoMGianniniFet alTechnical aspects for transcatheter aortic valve replacement with the novel balloon-expandable myval octacor. JACC Cardiovasc Interv. (2024) 17(1):101–3. 10.1016/j.jcin.2023.11.011

  • 34.

    LongQYeXZhaoQ. Artificial intelligence and automation in valvular heart diseases. Cardiol J. (2020) 27(4):404–20. 10.5603/CJ.a2020.0087

  • 35.

    TangGHLSpencerJRogersTGrubbKJGleasonPGadaHet alFeasibility of coronary access following redo-TAVR for evolut failure: a computed tomography simulation study. Circ Cardiovasc Interv. (2023) 16(11):e013238. 10.1161/CIRCINTERVENTIONS.123.013238

  • 36.

    BaigAAManionCKhawarWIDonnellyBMRaygorKTurnerRet alCerebral emboli detection and autonomous neuromonitoring using robotic transcranial Doppler with artificial intelligence for transcatheter aortic valve replacement with and without embolic protection devices: a pilot study. J Neurointerv Surg. (2024) 16(11):1167–73. 10.1136/jnis-2023-020812

  • 37.

    ButalaNMWoodDALiHChinnakondepalliKLauckSBSathananthanJet alEconomics of minimalist transcatheter aortic valve replacement: results from the 3M-TAVR economic study. Circ Cardiovasc Interv. (2022) 15(10):e012168. 10.1161/CIRCINTERVENTIONS.122.012168

  • 38.

    TianYPadmanabhanDMcLeodCJZhangPXiaoPSandhuGSet alUtility of 30-day continuous ambulatory monitoring to identify patients with delayed occurrence of atrioventricular block after transcatheter aortic valve replacement. Circ Cardiovasc Interv. (2019) 12(12):e007635. 10.1161/CIRCINTERVENTIONS.118.007635

  • 39.

    VijayaramanPCanoOKoruthJSSubzposhFANandaSPuglieseJet alHis-Purkinje conduction system pacing following transcatheter aortic valve replacement: feasibility and safety. JACC Clin Electrophysiol. (2020) 6(6):649–57. 10.1016/j.jacep.2020.02.010

  • 40.

    SchoechlinSEichenlaubMMuller-EdenbornBNeumannFJArentzTWestermannDet alRisk stratification for pacemaker implantation after transcatheter aortic valve implantation in patients with right bundle branch block. J Clin Med. (2022) 11(19):5580. 10.3390/jcm11195580

Summary

Keywords

transcatheter aortic valve replacement, bibliometric analysis, research hotspot, CiteSpace, VOSviewer

Citation

Lai P, Zhang D, Xue J, Xu S, Tian K, Zhang H, Wang B, Zhong Y and Liao Y (2025) Current hotspot and study trend of transcatheter aortic valve replacement, a bibliometric analysis from 2009 to 2023. Front. Cardiovasc. Med. 12:1411561. doi: 10.3389/fcvm.2025.1411561

Received

17 August 2024

Accepted

28 March 2025

Published

14 April 2025

Volume

12 - 2025

Edited by

Roney Orismar Sampaio, University of São Paulo, Brazil

Reviewed by

Giampiero Esposito, Monzino Cardiology Center (IRCCS), Italy

Peng Zhu, Southern Medical University, China

Updates

Copyright

© 2025 Lai, Zhang, Xue, Xu, Tian, Zhang, Wang, Zhong and Liao.

This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

*Correspondence: Yi-ming Zhong Yong-ling Liao

†These authors have contributed equally to this work

Disclaimer

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.

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