Transcatheter Aortic Valve Replacement: Comprehensive Review and Present Status

The interventional care for patients undergoing transcatheter aortic valve replacement: Establishing indicators for optimal interventional care

OBJECTIVE

We evaluate the quality of interventional care for patients undergoing transcatheter aortic valve replacement (TAVR) using a set of quality indicators.

METHODS

We developed an initial list of quality indicators by incorporating current guidelines, observing practice discrepancies, and basing it on the Donabedian "structure, process, and outcome" three-dimensional quality evaluation model as the framework. The Delphi method was utilized in two rounds of consultation involving 31 experts to evaluate and revise indicators at all levels.

RESULTS

The response rate of expert questionnaires was 100% for both rounds, and the expert authority coefficients were 0.913 and 0.940, respectively. The Kendall harmony coefficients were 0.221 and 0.195, respectively, with P < 0.05. Eventually, a quality evaluation system of interventional care for patients undergoing TAVR was constructed, consisting of three structural indicators, nine process indicators, and 42 outcome indicators.

CONCLUSIONS

The quality evaluation system for interventional care of TAVR sought to establish specific, objective, and quantifiable criteria for assessing the quality of care. It is recommended to apply the set of quality indicators across hospitals to enhance the quality of care for TAVR.

Immune response following transcatheter aortic valve procedure

Aortic valve stenosis is the most common type of heart valve disease in the United States and Europe and calcific aortic stenosis (AS) affects 2-7% of people aged 65 years and older. Aortic valve replacement (AVR) is the only effective treatment for individuals with this condition. Transcatheter Aortic Valve Replacement (TAVR) has been widely accepted as a minimally invasive therapeutic approach for addressing symptomatic AS in patients who are considered to have a high risk for traditional surgical intervention. TAVR procedure may have a paradoxical effect on the immune system and inflammatory status. A major portion of these immune responses is regulated by activating or inhibiting inflammatory monocytes and the complement system with subsequent changes in inflammatory cytokines. TAVR has the potential to induce various concurrent exposures, including disruption of the native valve, hemodynamic changes, antigenicity of the bioprosthesis, and vascular damage, which finally lead to the development of inflammation. On the other hand, it is important to acknowledge that TAVR may also have anti-inflammatory effects by helping in the resolution of stenosis.The inflammation and immune response following TAVR are complex processes that significantly impact procedural outcomes and patient well-being. Understanding the underlying mechanisms, identifying biomarkers of inflammation, and exploring therapeutic interventions to modulate these responses are crucial for optimizing TAVR outcomes. Further research is warranted to elucidate the precise immunological dynamics and develop tailored strategies to attenuate inflammation and enhance post-TAVR healing while minimizing complications.

Artificial intelligence in cardiac computed tomography

Artificial Intelligence (AI) is a broad discipline of computer science and engineering. Modern application of AI encompasses intelligent models and algorithms for automated data analysis and processing, data generation, and prediction with applications in visual perception, speech understanding, and language translation. AI in healthcare uses machine learning (ML) and other predictive analytical techniques to help sort through vast amounts of data and generate outputs that aid in diagnosis, clinical decision support, workflow automation, and prognostication. Coronary computed tomography angiography (CCTA) is an ideal union for these applications due to vast amounts of data generation and analysis during cardiac segmentation, coronary calcium scoring, plaque quantification, adipose tissue quantification, peri-operative planning, fractional flow reserve quantification, and cardiac event prediction. In the past 5 years, there has been an exponential increase in the number of studies exploring the use of AI for cardiac computed tomography (CT) image acquisition, de-noising, analysis, and prognosis. Beyond image processing, AI has also been applied to improve the imaging workflow in areas such as patient scheduling, urgent result notification, report generation, and report communication. In this review, we discuss algorithms applicable to AI and radiomic analysis; we then present a summary of current and emerging clinical applications of AI in cardiac CT. We conclude with AI's advantages and limitations in this new field.

Plasma N-terminal pro-B-type natriuretic peptide in the detection of aortic valve stenosis

BACKGROUND

Systolic murmur suggestive of aortic valve origin is a common accidental finding, particularly in the elderly. Usually, it is due to aortic stenosis (AS) or aortic sclerosis (ASc). Currently, echocardiography is used to differentiate AS from ASc. Plasma N-terminal (NT)-prohormone BNP (NT-proBNP) is known to correlate with the severity of AS. We assessed whether NT-proBNP separates AS from ASc.

METHODS

The study population consisted of three groups: AS (n = 87, age 77 ± 7 years), ASc (n = 76, age 72 ± 10 years), and healthy controls (n = 101, age 55 ± 10 years). All subjects underwent transthoracic echocardiography and measurement of plasma NT-proBNP. Patients with diseases known to increase NT-proBNP were excluded.

RESULTS

The crude plasma NT-proBNP (median; IQR) in AS patients (413; 165-1055 ng/l) was significantly higher compared to ASc patients (96; 53-237 ng/l, p < 0.001) and healthy controls (50; 29-76 ng/l, p < 0.001). After adjusting for the confounding factors (age, coronary artery disease, renal function and diastolic blood pressure), plasma NT-proBNP remained significantly higher in AS patients as compared to ASc (p < 0.002) and controls (p < 0.0001). In the receiver-operating characteristic curve for NT-proBNP to identify AS from ASc and controls, the area under the curve was 0.878 with optimal cutoff of 115 ng/l. In addition, using 115 ng/l to separate AS from ASc yielded sensitivity of 0.885, and negative predictive value of 0.808.

CONCLUSIONS

NT-proBNP was sensitive to identify AS and useful to rule out AS in patients with systolic murmur in the left ventricular outflow tract provided the patient does not have coexisting disease known to impact NT-proBNP.

High-Flow Oxygen Therapy in the Perioperative Setting and Procedural Sedation: A Review of Current Evidence

High-flow oxygen therapy (HFOT) is a respiratory support system, through which high flows of humidified and heated gas are delivered to hypoxemic patients. Several mechanisms explain how HFOT improves arterial blood gases and enhances patients' comfort. Some mechanisms are well understood, but others are still unclear and under investigation. HFOT is an interesting oxygen-delivery modality in perioperative medicine that has many clinical applications in the intensive care unit (ICU) and the operating room (OR). The purpose of this article was to review the literature for a comprehensive understanding of HFOT in the perioperative period, as well as its uses in procedural sedation. This review will focus on the HFOT definition, its physiological benefits, and their mechanisms, its clinical uses in anesthesia, and when it is contraindicated.

Mortality Outcomes in Patients With Cardiac Implantable Electronic Devices Before and After Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR) carries a risk of high-grade AV block requiring cardiac implantable electronic device (CIED) implantation, which has been associated with a higher mortality rate. However, the outcomes of TAVR in patients with preexisting CIEDs are not well understood. We conducted a retrospective analysis of consecutive patients who underwent TAVR from December 2014 to December 2019 at our institution. Patients were categorized into 3 groups: preexisting CIED pre-TAVR (group 1), CIED implanted within 30 days after TAVR (group 2), and no CIED implanted (group 3). Cox proportional hazard was conducted to determine the primary end point of all-cause mortality. A total of 366 patients were included, of whom 93 (25.4%), 51 (13.9%), and 222 (60.7%) comprised group 1, 2, and 3, respectively. The median follow-up time was 2.3 years. The all-cause mortality rate was higher in group 1 than group 2 (hazard ratio [HR] 2.60, 95% confidence interval [CI] 1.09 to 6.18, p = 0.03) and group 3 (HR 1.96, 95% CI 1.24 to 3.08, p = 0.004). On the multivariate analysis, there was no statistically significant difference in mortality among the groups (group 1 vs group 2: HR 1.95, 95% CI 0.70 to 5.44, p = 0.20 and group 1 vs group 3: HR 1.27, 95% CI 0.66 to 2.43, p = 0.47). Preoperative hemoglobin ≤12 g/100 ml was an independent predictor of all-cause mortality (HR 1.75, 95% CI 1.10 to 2.80, p = 0.02). Group 1 had a higher 1 year congestive heart failure readmission rate (29%) than group 2 (17.6%) and group 3 (8.1%; p <0.0001). In conclusion, there was no difference in the adjusted long-term survival based on the CIED grouping. However, patients with preexisting CIEDs had higher all-cause mortality and 1-year congestive heart failure readmission rates owing to their higher co-morbidity burden, irrespective of their Society of Thoracic Surgeons score. This can be taken into account for preoperative risk stratification.

Where are we getting it wrong? Prevalence and causes of unplanned SAVR in a UK regional cardiac centre

Surgical aortic valve replacement (SAVR) prolongs life and improves its quality in patients with severe aortic stenosis (AS). Unplanned SAVR is a failure of AS screening and follow-up programmes. We identified all elective, first, isolated SAVRs performed between 1 January and 31 December 2019 in a Welsh tertiary cardiac centre, and documented the clinical and echocardiographic variables, and reasons for unplanned SAVR. Of 140 isolated SAVR, 37 (26%) were unplanned (16 female, mean age 72.3 ± 8.4 years). Twenty had been on the SAVR waiting list and had expedited operations because of concerns about the severity of the AS (12 patients), or because of acute (four patients) or chronic (four patients) left ventricular failure (LVF). Of the 17 not on the waiting list, AS was known in seven: three had acute pulmonary oedema while under follow-up with 'moderate AS', one had been referred but developed pulmonary oedema while waiting for a surgical outpatient appointment, one refused SAVR but was subsequently admitted with acute pulmonary oedema and accepted SAVR, one was admitted directly from home because concerns about worsening AS, and one had infective endocarditis with severe aortic regurgitation. Of 10 patients with a new diagnosis of AS, five presented with LVF, four with angina and in three there was a history of syncope (p=0.003 vs. known AS; multiple symptoms). Survival, age, Canadian Cardiovascular Society (CCS) and New York Heart Association (NYHA) class, number of risk factors, peak and mean aortic valve (AV) gradients, AV area, and stroke volume index were not different between patients who had planned versus unplanned SAVR, or with known or new AS. Patients with a new diagnosis of AS had longer pre-operative wait (22.3 ± 9.3 vs. 6.0 ± 10.3 days, p<0.001). In conclusion, a quarter of SAVRs are unplanned and half are in patients without a prior diagnosis of AS. Unplanned SAVR is associated with prolonged length of hospital stay and with a history of syncope, but other conventional clinical and echocardiographic parameters do not differ between patients undergoing planned versus unplanned SAVR.

All-cause procedural readmissions following transcatheter aortic valve replacement

Objective

With expanding eligibility criteria, transcatheter aortic valve replacement is being performed on patients with longer life expectancy, and subsequent procedures after index transcatheter aortic valve replacement are inevitable. This study examines the incidence and outcomes of patients undergoing subsequent procedural readmissions after transcatheter aortic valve replacement.

Methods

All patients who underwent index transcatheter aortic valve replacement and were discharged alive from January 2012 to December 2019 at a single institution were evaluated. Study end points were mortality and readmission for procedure with more than 1-day hospital stay. Effect on survival was evaluated by treating procedural readmission as a time-dependent variable by Cox proportional hazard model and competing risk analysis.

Results

A total of 1092 patients met inclusion criteria with a median follow-up time of 34 months. A total of 218 patients (20.0%) had 244 subsequent procedural readmissions. During the 244 procedural readmissions, there were 260 procedures; 96 (36.9%) were cardiac (most commonly pacemaker implantation, percutaneous coronary interventions, and surgical aortic valve replacements), and 164 (63.1%) were noncardiac (most commonly orthopedic and gastrointestinal procedures). The overall procedural readmission rates were 32%, 39%, and 42%, and all-cause mortality was 27%, 44%, and 54% at 20, 40, and 60 months, respectively. Procedural readmissions were not associated with a survival penalty in any surgical risk group or on Cox regression (hazard ratio, 1.25; 0.91-1.64, P = .17).

Conclusions

After transcatheter aortic valve replacement, procedural interventions are seen frequently, with most procedures occurring within the first year after transcatheter aortic valve replacement. However, subsequent procedural readmissions do not appear to have a survival penalty for patients after transcatheter aortic valve replacement. After transcatheter aortic valve replacement with resolution of aortic stenosis, subsequent procedures can and should be pursued if they are needed.

Economic Justification Analysis of Minimally Invasive versus Conventional Aortic Valve Replacement

There is no definitive consensus about the cost-effectiveness of minimally invasive aortic valve replacement (AVR) (MI-AVR) compared to conventional AVR (C-AVR). The aim of this study was to compare the rate of postoperative complications and total hospital costs of MI-AVR versus C-AVR overall and by the type of aortic prosthesis (biological or mechanical). Our single-center retrospective study included 324 patients over 18 years old who underwent elective isolated primary AVR with standard stented AV prosthesis at the Institute for Cardiovascular Diseases "Dedinje" between January 2019 and December 2019. Reintervention, emergencies, combined surgical interventions, and patients with sutureless valves were excluded. In both MI-AVR and C-AVR, mechanical valve implantation contributed to overall reduction of hospital costs with equal efficacy. The cost-effectiveness ratio indicated that C-AVR is cheaper and yielded a better clinical outcome with mechanical valve implantation (67.17 vs. 69.5). In biological valve implantation, MI-AVR was superior. MI-AVR patients had statistically significantly higher LVEF and a lower Euro SCORE than C-AVR patients (Mann-Whitney U-test, p = 0.002 and p = 0.002, respectively). There is a slight advantage to MI-AVR vs. C-AVR, since it costs EUR 9.44 more to address complications that may arise. Complications (mortality, early reoperation, cerebrovascular insult, pacemaker implantation, atrial fibrillation, AV block, systemic inflammatory response syndrome, wound infection) were less frequent in the MI-AVR, making MI-AVR more economically justified than C-AVR (18% vs. 22.1%).

Transcatheter aortic valve implantation in patients with anomalous coronary artery

OBJECTIVES

The aim of this review was to analyze literature and provide systematic algorithm to guide decision making during TAVI procedure.

BACKGROUND

Transcatheter aortic valve implantation (TAVI) is growing in popularity and expanding to younger patients with lower risk profiles. Currently, there is no concise guideline on the management strategy during TAVI in patients with anomalous coronary artery (ACA) anatomy undergoing this procedure.

METHODS

A systematic search was conducted for relevant case reports of TAVI in patients who had confirmed ACA anatomy. Twenty-four case reports, that met the criteria for this review, were identified and included in the final study size.

RESULTS

TAVI was successful in 23 out of 24 cases. Half of the cases (12) described performing balloon aortic valvuloplasty (BAV) before TAVI. The majority (15) reported using angiogram Postimplantation. Only one-third of cases (8) reported performing coronary protection (with either wire, wire and stent or wire and balloon). Two-third of case reports (16/24, 67%) mentioned using Edwards SAPIEN balloon expandable transcatheter heart valves (THV).

CONCLUSIONS

Preprocedural diagnostic imaging tests play important role in determining the ACA anatomy and its relation to the aortic valve. BAV with simultaneous coronary arteries angiography or aortography should be performed before implantation of THV, as it could potentially predict whether the ACA would be compressed. Using at least a coronary wire for ACA protection is recommended in case there is high risk of ACA obstruction. Management strategy should be individualized when performing TAVI in patients with ACA.

Association between periprocedural myocardial injury and long-term all-cause mortality in patients undergoing transcatheter aortic valve replacement: a systematic review and meta-analysis

Objective. The purpose of this meta-analysis was to investigate the effect of periprocedural myocardial injury (PPMI) on long-term all-cause mortality in patients undergoing transcatheter aortic valve replacement (TAVR) and to explore potential factors associated with mortality risk. Design. The PubMed, Embase, and Cochrane Library databases were searched up to April 2022. Studies reporting the effect of PPMI on the risk of long-term all-cause mortality were included. The summary odds ratio (OR) was calculated using a random effects model. Additionally, meta-regression and subgroup analyses were conducted according to specific research characteristics to explore sources of heterogeneity. Results. Fourteen studies involving 6,415 patients who underwent TAVR showed that the occurrence of PPMI was associated with a higher risk of long-term mortality. Subgroup analysis showed that in the group of aged ≥82 years, men accounted for less than 50%, coronary artery disease patients accounted for more than 50%, and the proportion of patients with chronic kidney disease accounted for more than 60%, the proportion of patients with atria fibrillation accounted for less than 30%, and the Society of Thoracic Surgeons predicted risk of mortality score was >8 points, patients with PPMI had higher long-term all-cause mortality than those without PPMI. Conclusions. Among the patients who underwent TAVR, those who developed PPMI had higher long-term all-cause mortality.

Intracardiac echocardiography Chinese expert consensus

In recent years, percutaneous catheter interventions have continuously evolved, becoming an essential strategy for interventional diagnosis and treatment of many structural heart diseases and arrhythmias. Along with the increasing complexity of cardiac interventions comes ever more complex demands for intraoperative imaging. Intracardiac echocardiography (ICE) is well-suited for these requirements with real-time imaging, real-time monitoring for intraoperative complications, and a well-tolerated procedure. As a result, ICE is increasingly used many types of cardiac interventions. Given the lack of relevant guidelines at home and abroad and to promote and standardize the clinical applications of ICE, the members of this panel extensively evaluated relevant research findings, and they developed this consensus document after discussions and correlation with front-line clinical work experience, aiming to provide guidance for clinicians and to further improve interventional cardiovascular diagnosis and treatment procedures.

Aetiology of chronic heart failure in patients from a super-aged society: the KUNIUMI registry chronic cohort

AIMS

With the rapidly increasing ageing population, heart failure is an urgent challenge, particularly in developed countries. The study aimed to investigate the main aetiologies of chronic heart failure in a super-aged society.

METHODS AND RESULTS

The KUNIUMI registry chronic cohort is a community-based, prospective, observational study of chronic heart failure in Awaji Island, Japan. Inhabitants of this island aged ≥65 years accounted for 36.3% of the population. In the present study, data from patients with symptomatic heart failure were extracted from the registry. A total of 1646 patients were enrolled from March 2019 to March 2021, accounting for ~1.3% of the inhabitants of Awaji Island. We analysed 852 patients with symptomatic heart failure. The mean age was high (78.7 ± 11.1 years), with 357 patients (41.9%) being female. The proportion of women increased significantly with advancing age and constituted more than half of the patients aged 85 years and older (P < 0.01). The prevalence of atrial fibrillation, and in particular long-standing persistent atrial fibrillation, increased at 70 years of age (P < 0.01). The proportion of patients with heart failure with preserved ejection fraction increased to ~60% when age was over 75 years. Although ischaemic heart disease accounted for 35.0% of chronic heart failure aetiologies, valvular heart disease was the most common cause of chronic heart failure (49.8%). The major types of valvular heart disease were mitral regurgitation and tricuspid regurgitation (27.2% and 21.7%, respectively), both of which increased significantly with age (P < 0.01). The incidence of aortic valve stenosis increased markedly over the age of 85 years (P < 0.01). Atrial functional mitral regurgitation increased with age and was the major cause of mitral regurgitation in patients aged >75 years. Patients with atrial functional mitral regurgitation had a higher prevalence of atrial fibrillation (especially long-standing persistent atrial fibrillation) and a larger left atrial volume index when compared with patients with other types of mitral regurgitation (P < 0.001, respectively).

CONCLUSIONS

The KUNIUMI registry chronic cohort showed a change in heart failure aetiology to valvular heart disease in a super-aged society. Effective and comprehensive countermeasures are required to prepare for the rapid rise in heart failure incidence in a super-aged society.

Silent Brain Infarction, Delirium, and Cognition in Three Invasive Cardiovascular Procedures: a Systematic Review

Silent brain infarctions (SBIs) are brain lesions noted on neuroimaging that are not associated with clinical symptoms. SBIs are associated with a number of vascular risk factors and are common following invasive cardiovascular procedures such as atrial fibrillation (AF) ablation, coronary artery bypass graft (CABG), and transcatheter aortic valve replacement (TAVR). Although not eliciting signs of clinical stroke, SBIs are associated with increased frailty, and motor and mood features. Less is known, however, about the relationship between SBI, cognition, and delirium following invasive cardiac procedures and most investigations into these relationships have been reported in large-scale epidemiological studies. In the current paper, we conducted a systematic review to evaluate evidence of a relationship between SBI, delirium, and cognitive decline following CABG, AF ablation, and TAVR. Twenty studies met inclusion criteria. In general, our review identified conflicting results for each cardiac procedure, with some studies suggesting a relationship between SBI, cognitive impairment, and delirium, whereas others showed no relationship between SBI, cognitive impairment, and delirium. Potential reasons for this discrepancy as well as suggestions for future research are discussed.

Examination of the most cited studies on transcatheter aortic valve replacement with bibliometric analysis

AIM

The aim of this study is to analyze the studies on TAVI with the bibliometric method and to perform a scientiometric analysis of the top 100 most cited articles for researchers.

METHODS

The Thomson Reuters Web of Science database was searched for all relevant articles using the terms "TAVR" and "TAVI". The results were ordered according to the number of citations. We also analyzed the 100 most cited articles (T100) by annual average citation count (ACpY), years, research methods, author, institution, journal, funding agencies, and keywords. Analyses were also performed between the total number of citations, ACpY, impact factors, and publication time.

RESULTS

The article titled "Transcatheter Aortic-Valve Implantation for Aortic Stenosis in Patients Who Cannot Undergo Surgery" was the most cited article (n = 4616). The article titled "Transcatheter Aortic-Valve Replacement with a Balloon-Expandable Valve in Low-Risk Patients" had the highest ACpY count (n = 497). The United States was the country that contributed the most to the T100 list. While the journal that contributed the most with 32 articles was "Journal of the American College Of Cardiology", the journal in which the top 10 most cited articles were published most frequently was the "New England Journal of Medicine". In addition, the most publications were made in 2012.

CONCLUSION

Although this bibliometric analysis study has some limitations, it allows the most cited publications on TAVI to be analyzed systematically and provides scientific contributions.

Artificial Intelligence-Based Spiral CT 3D Reconstruction in Transcatheter Aortic Valve Implantation

To evaluate the clinical application effect of spiral computed tomography (CT) three-dimensional (3D) reconstruction based on artificial intelligence in transcatheter aortic valve implantation (TAVI), a CT 3D reconstruction model based on deep convolutional neural networks (DCNN) was established in this research, which was compared with the model-based iterative reconstruction (MBIR) and used in clinical practice. Then, 62 patients with aortic stenosis (AS) who underwent TAVI surgery were recruited as the research objects. The accuracy, sensitivity, and specificity of the multislice spiral CT scan (MSCT) and transthoracic echocardiography (TTE) in predicting the type of TAVI surgical valve were compared and analyzed. The results showed that the mean absolute error (MAE) (0.01) and root mean square error (RMSE) (0.086) of the MBIR model were higher than the reconstruction model in this research. The structural similarity (SSIM) (0.831) and peak signal-to noise ratio (PSNR) (32.77 dB) of the MBIR model were lower than the reconstruction model, and the differences were considerable ( $P<0.05$ ). Of the valve models selected based on the TTE measurement results, 35 cases were accurately predicted and 27 cases were incorrectly predicted. The accuracy of MSCT was 87.1%, the specificity was 98.84%, and the sensitivity was 92.87%; all of which were significantly higher than TTE ( $P<0.05$ ). In summary, compared with the MBIR reconstruction model, the imaging results of the model established in this research were closer to the real image. Compared with TTE, MSCT had higher accuracy, sensitivity, and specificity and can provide more accurate preoperative predictions for patients undergoing TAVI surgery.

Transaxillary Versus Transaortic Transcatheter Aortic Valve Implantation in the Treatment of Aortic Stenosis: An Updated Systematic Review and Meta-Analysis

Transcatheter aortic valve replacement (TAVR) is a technique that can be performed through multiple approaches, and the benefits of one approach over another are still being evaluated to make sure patients receive the best possible care. Our meta-analysis aims to compare clinical and procedural outcomes of the transaxillary (TAx) and transaortic (TAo) approaches to validate the more optimal procedure.

The systematic literature search was done via PubMed/MEDLINE, Embase, and the Cochrane Central databases from inception to December 2021, to identify articles reporting data on both TAx TAVR and TAo TAVR. In addition, we checked ClinicalTrials.gov for more published or unpublished trials. Baseline patient characteristics, procedure results, and clinical results were extracted from the article and pooled for analysis. A quantitative meta-analysis was conducted using Review Manager (RevMan) version 5.3 (Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark). The outcomes extracted included blood transfusion, conversion to sternotomy, tamponade, contrast amount, procedure time, bleeding incidents (minor, major, or life-threatening), length of stay (LOS), vascular complications (minor or major), acute kidney injury (AKI), paravalvular leak (PVL), permanent pacemaker (PPM) implantation, 30-day mortality, one-year mortality, 30-day stroke, and device success.

The final analysis included 11 articles, consisting of 10 observational studies and a pivotal trial. Cumulative results revealed that the TAo approach had a significantly lower incidence of vascular complications (RR = 2.30; 95% CI = 1.22 to 4.35), and the need for implantation of a permanent pacemaker (RR = 1.82; 95% CI = 1.30 to 2.54) along with a lower amount of contrast (mean difference (MD) = 27.40; 95% CI = 3.73 to 51.08) needed to be used. The TAx group was associated with a significantly lower 30-day mortality (RR = 0.46; 95% CI = 0.31 to 0.69), AKI (RR = 0.47; 95% CI = 0.33 to 0.67), and length of hospital stay (MD = −1.95; 95% CI = −2.51 to −1.38). No significant difference was observed between the outcomes of 30-day stroke (RR = 1.38; 95% CI = 0.81 to 2.33), PVL (RR = 1.05; 95% CI = 0.50 to 2.18), tamponade (RR = 0.71; 95% CI = 0.12 to 4.03), conversion to sternotomy (RR = 0.51; 95% CI = 0.06 to 4.30), device success (RR = 0.97; 95% CI = 0.88 to 1.07), the incidence of bleeding (RR = 0.75; 95% CI = 0.51 to 1.10), and procedure time (MD = 4.44; 95% CI = −96.30 to 105.17).

Both the procedures were associated with their benefits and risks. Although most of the outcomes favored TAx transcatheter aortic valve implantation (TAVI), it is too early to say if it would be better than TAo TAVI. To authenticate the findings concluded in this meta-analysis and further improve our understanding of the efficacy, safety, and risk profile between TAx and TAo approaches for TAVI, large sample randomized clinical trials are required on a wide scale.

Endothelial Progenitor Cell-Based in vitro Pre-Endothelialization of Human Cell-Derived Biomimetic Regenerative Matrices for Next-Generation Transcatheter Heart Valves Applications

Hemocompatibility of cardiovascular implants represents a major clinical challenge and, to date, optimal antithrombotic properties are lacking. Next-generation tissue-engineered heart valves (TEHVs) made from human-cell-derived tissue-engineered extracellular matrices (hTEMs) demonstrated their recellularization capacity in vivo and may represent promising candidates to avoid antithrombotic therapy. To further enhance their hemocompatibility, we tested hTEMs pre-endothelialization potential using human-blood-derived endothelial-colony-forming cells (ECFCs) and umbilical vein cells (control), cultured under static and dynamic orbital conditions, with either FBS or hPL. ECFCs performance was assessed via scratch assay, thereby recapitulating the surface damages occurring in transcatheter valves during crimping procedures. Our study demonstrated: feasibility to form a confluent and functional endothelium on hTEMs with expression of endothelium-specific markers; ECFCs migration and confluency restoration after crimping tests; hPL-induced formation of neo-microvessel-like structures; feasibility to pre-endothelialize hTEMs-based TEHVs and ECFCs retention on their surface after crimping. Our findings may stimulate new avenues towards next-generation pre-endothelialized implants with enhanced hemocompatibility, being beneficial for selected high-risk patients.

Evolving Indications of Transcatheter Aortic Valve Replacement Compared to Surgical Valve Replacement: A Review of the Current Literature

Patients with severe symptomatic aortic stenosis (AS) are categorized into high risk, intermediate risk, and low risk. The identification of risk status is done using the Society of Thoracic Surgeons mortality score. Various factors are considered such as clinical symptoms, ejection fraction, age, left ventricle measurements, severity of AS, associated comorbid factors, and any other associated cardiac diseases. Surgery is still a standard practice in many countries. However, it has its own complications, especially in high-risk patients. Transcatheter intervention is getting precipitous recognition as an alternative mode of treatment in selected cases to mitigate complication rates and improve quality of life. In this article, transcatheter aortic valve replacement and surgical aortic valve replacement are compared in patients with different surgical risks. The impact of the cost of the procedure and quality of life are of paramount importance in choosing the type of intervention. Structural valve degeneration is an independent risk factor affecting patient outcomes. Modifications in valve designs are being constantly implemented as well. The standard analytical methods are in accordance with randomized clinical trials to determine the efficacy and outcome of procedures. Primary and secondary endpoints were considered to evaluate the data. The results were tabulated to derive statistical significance of the studies. In high-risk surgical patients, transcatheter intervention has been proven as the procedure of choice for valve replacement. However, intermediate-risk and low-risk categories need further studies.

Transfemoral Versus Subclavian Access for Transcatheter Aortic Valve Replacement

OBJECTIVE

This study sought to compare outcomes of transcatheter aortic valve replacement (TAVR) performed through subclavian access with those performed through transfemoral access.

METHODS

This was an observational study utilizing an institutional TAVR database from 2010 to 2018. All patients undergoing a TAVR via a transfemoral (TF-TAVR) or subclavian (SC-TAVR) approach were included in the study. The groups were analyzed for differences in operative mortality and postoperative outcomes. Multivariable Cox analysis was performed to identify variables associated with long-term survival after TAVR.

RESULTS

Of the 1,095 patients identified, 133 patients underwent SC-TAVR and 962 patients underwent TF-TAVR. Patients who underwent SC-TAVR were younger, more likely to have chronic lung disease and peripheral vascular disease, had higher Society of Thoracic Surgeons predicted risk of mortality scores, and were more likely to have self-expanding valves placed (P < 0.05). Operative mortality was similar between the TF-TAVR (2.7%) and SC-TAVR (3.8%) groups. There were no significant differences in stroke, length of stay, 30-day readmission, blood transfusions, acute kidney injury, need for permanent pacemaker, paravalvular leak, or major vascular complications between the groups (P > 0.05). The unadjusted Kaplan-Meier survival estimate for TF-TAVR was significantly higher than for SC-TAVR (P = 0.009, log-rank). However, on multivariable Cox analysis, subclavian access was not significantly associated with an increased hazard of death as compared with transfemoral access (P = 0.21).

CONCLUSIONS

Outcomes of SC-TAVR are comparable to those of TF-TAVR. Subclavian access may be a favorable alternative approach when TF-TAVR is contraindicated.

Current and future transcatheter aortic valve replacement valves

PURPOSE OF REVIEW

This review analyzes currently available commercial transcatheter aortic valve replacement (TAVR) valves as well as valves in investigational status and those in preclinical testing. The design features and clinical outcomes of the Edwards SAPIEN S3 and Medtronic Evolut PRO+ are described and compared with highlight clinical circumstances where one may be favoured over the other.

RECENT FINDINGS

Multiple randomized and nonrandomized trials have compared commercial and investigational TAVR valves. The results of these are summarized and discussed within this review with a focus on how the SAPIEN S3 and Evolut PRO+ both compare to each other as well as various valves in different investigational stages.

SUMMARY

TAVR is an innovative and ground-breaking technology that will forever have revolutionized the management of aortic stenosis. Though the technology and valves themselves have come a long way, further developments are necessary if we are to continue to expand its indications and achieve a safer perioperative experience with more durable valves.

Low-Risk Surgical Aortic Valve Replacement in the Era of Transcatheter Aortic Valve Implantation

Open surgical aortic valve replacement (SAVR) is a viable alternative to transcatheter implantation in low-risk patients. In this light, we evaluated the safety and effectiveness of SAVR performed through conventional and less invasive surgical approaches in a high-volume center.

We retrospectively reviewed the records of 395 consecutive patients who underwent open SAVR from January 2019 through December 2019 in our center. We evaluated and compared the operative results and postoperative major adverse outcomes of 3 surgical approaches: full median sternotomy (n=267), upper ministernotomy (ministernotomy) (n=106), and right anterior thoracotomy (minithoracotomy) (n=22).

Overall, the 30-day all-cause mortality rate was 0.8% (3 patients). Stroke occurred in 8 patients (2%), disabling stroke in 4 patients (1%), myocardial infarction in 1 (0.2%), and surgical site infection in 13 (3.2%). There was no difference in 30-day mortality rate or incidence of postoperative major adverse events among the 3 surgical groups. Stroke and surgical site infection occurred more frequently, but not significantly so, in the full-sternotomy group. The mean hospital stay was longer after full sternotomy (9.1 ± 5.5 d) than after ministernotomy (7.5 ± 2.9 d) or minithoracotomy (7.4 ± 1.9 d) (P=0.012).

Our findings suggest that open SAVR performed in a high-volume center is associated with a low early mortality rate and that less invasive approaches result in faster postoperative recovery and shorter hospital stays.

Radial versus femoral secondary access for transcatheter aortic valve replacement: A systematic review and meta-analysis

OBJECTIVES

We aimed to evaluate the risk of procedural complications after TAVR using secondary radial access (RA) versus femoral access (FA) through a systematic review and meta-analysis of the published literature.

BACKGROUND

Transcatheter aortic valve replacement (TAVR) entails both large-bore arterial access for device delivery and secondary arterial access for hemodynamic and imaging assessments. It is unknown whether RA versus FA for this secondary access reduces the risk of procedural complications.

METHODS

We searched PubMed, Embase, the Cochrane Library, and Web of Science for observational studies comparing TAVR procedural complications in RA versus FA. Event rates were compared via weighted summary odds ratios using the Mantel-Haenszel method.

RESULTS

Six manuscripts encompassing 6132 patients were included. Meta-analysis showed that RA reduced the risk of major vascular complications (OR 0.58, 95% CI 0.43-0.77, p < 0.001, I² 0%) and major/life-threatening bleeding (OR 0.46, 95% CI 0.36-0.59, p < 0.001, I² 0%) as compared to FA for secondary TAVR access. We also observed a reduction 30-day mortality (OR 0.55, 95% CI 0.38-0.79, p = 0.001, I² 0%), acute kidney injury (OR 0.45, 95% CI 0.34-0.60, p < 0.001, I² 0%), and stroke and transient ischemic attack (OR 0.43, 95% CI 0.27-0.67, p < 0.001, I² 0%).

CONCLUSIONS

RA reduced the risk of major vascular and bleeding complications when compared to FA for secondary access in TAVR. RA is associated with reduced risk of other adverse outcomes including mortality, but these associations may be related to selection bias and confounding given the observational study designs.

Inadequate Cardiac Unloading Following Transcatheter Aortic Valve Replacement

Background: Although many risk factors have been reported to be associated with poor clinical outcomes following transcatheter aortic valve replacement (TAVR), the implications of inadequate cardiac unloading following TAVR remain unknown. We investigated the prognostic impact of inadequate cardiac unloading following TAVR. Methods and Results: We retrospectively analyzed a cohort of patients with severe aortic stenosis who underwent invasive hemodynamic assessment following TAVR. The impact of inadequate cardiac unloading, defined as an elevated pulmonary capillary wedge pressure (PCWP), on the composite primary endpoint of cardiovascular mortality or heart failure readmission was investigated. Eighty-two patients (median age 86 years; 57 women) were included. Median PCWP following TAVR was 9 mmHg (interquartile range 7-13 mmHg). A higher PCWP tended to be associated with an increased risk of adverse cardiovascular events (adjusted hazard ratio 1.18; 95% confidence interval 0.99-1.41). A cut-off value of PCWP >12 mmHg, calculated by time-dependent receiver operating characteristics analysis, stratified the cumulative incidence of the primary endpoint (2-year incidence of 36% vs. 8%). Uptitration of the diuretic dose was associated with event freedom among those with PCWP >12 mmHg. Conclusions: Inadequate cardiac unloading following TAVR was associated with an increased risk of adverse clinical events. Uptitration of medical therapies to improve cardiac hemodynamics after TAVR may reduce this risk.

Detecting Aortic Valve Anomaly From Induced Murmurs: Insights From Computational Hemodynamic Models

Patients who receive transcatheter aortic valve replacement are at risk for leaflet thrombosis-related complications, and can benefit from continuous, longitudinal monitoring of the prosthesis. Conventional angiography modalities are expensive, hospital-centric and either invasive or employ potentially nephrotoxic contrast agents, which preclude their routine use. Heart sounds have been long recognized to contain valuable information about individual valve function, but the skill of auscultation is in decline due to its heavy reliance on the physician's proficiency leading to poor diagnostic repeatability. This subjectivity in diagnosis can be alleviated using machine learning techniques for anomaly detection. We present a computational and data-driven proof-of-concept analysis of a novel, auscultation-based technique for monitoring aortic valve, which is practical, non-invasive, and non-toxic. However, the underlying mechanisms leading to physiological and pathological heart sounds are not well-understood, which hinders development of such a technique. We first address this by performing direct numerical simulations of the complex interactions between turbulent blood flow in a canonical ascending aorta model and dynamic valve motion in 29 cases with healthy and stenotic valves. Using the turbulent pressure fluctuations on the aorta lumen boundary, we model the propagation of heart sounds, as elastic waves, through the patient's thorax. The heart sound may be recorded on the epidermal surface using a stethoscope/phonocardiograph. This approach allows us to correlate instantaneous hemodynamic phenomena and valve motion with the acoustic response. From this dataset we extract "acoustic signatures" of healthy and stenotic valves based on principal components of the recorded sound. These signatures are used to train a linear discriminant classifier by maximizing correlation between recorded heart sounds and valve status. We demonstrate that this classifier is capable of accurate prospective detection of anomalous valve function and that the principal component-based signatures capture prominent audible features of heart sounds, which have been historically used by physicians for diagnosis. Further development of such technology can enable inexpensive, safe and patient-centric at-home monitoring, and can extend beyond transcatheter valves to surgical as well as native valves.

Estimation of Aortic Valve Calcium Score Based on Angiographic Phase Versus Reduction of Ionizing Radiation Dose in Computed Tomography

The aim of the study was to evaluate the estimation efficacy of aortic valve calcium score (AVCS) based on the multislice computed tomography (MSCT) angiographic phase. The evaluation of the reduced amount of ionizing radiation dose was performed because of this estimation. The study included 51 consecutive patients who qualified for transcatheter aortic valve implantation (TAVI) (78.59 ± 5.72 years). All subjects underwent MSCT: in the native phase dedicated to AVCS as well as angiographic phases aimed to morphologically assess the aortic ostium and arterial accesses for TAVI. Based on the native phase, an AVCS assessment was performed for axial reconstructions at 3.0 mm and 2.0 mm slice thickness (AVCS_native3.0 and AVCS_native2.0). Based on the angiographic phase AVCS was estimated for axial reconstruction at 0.6 mm slice thickness with increased values of lesion density in aortic valve cusps/aortic valve annulus, which is considered a calcification, from a typical value of 130 HU to 500 HU and 600 HU (AVCS_{CTA0.6 500 HU} and AVCS_{CTA0.6 600 HU}). Mathematical formulations were developed, allowing for AVCS native calculation based on AVCS values estimated based on the angiographic phase: AVCS_native3.0 = 813.920 + 1.510 AVCS_{CTA0.6 500 HU}; AVCS_native3.0 = 1235.863 + 1.817 AVCS_{CTA0.6 600 HU}; AVCS_native2.0 = 797.471 + 1.393 AVCS_{CTA0.6 500 HU}; AVCS_native2.0 = 1228.310 + 1.650 AVCS_{CTA0.6 600 HU}. The amount of a potential reduction in dose length product (DLP) in the case of AVCS estimation was 4.45 ± 1.54%. In summary, relying solely on the angiographic phase of MSCT examination before TAVI, it is possible to conclusively estimate AVCS. This estimation results in a marked reduction in radiation dose in MSCT.

Acute Kidney Injury in Transcatheter Aortic Valve Replacement

Introduction

Transcatheter aortic valve replacement (TAVR) has been established as a standard of care for patients with severe aortic stenosis. We aim to study the predictors of acute kidney injury (AKI) after TAVR from a contemporary analysis using the National Inpatient Sample (NIS) database.

Methods

We performed a national analysis using the NIS database to evaluate predictors of acute kidney injury (AKI) after TAVR. Our study period was from 2015 to 2018, and we identified TAVR patients in all procedure fields. Patients aged less than 18 years were excluded from the study.

Results

We report data of 173,760 TAVR patients, of which 20,045 (11.5%) had AKI and 153,715 (88.4%) did not. There were three principal findings of our study. First, mortality was higher in patients with AKI compared to patients who did not have AKI (8% vs. 0.8%; p<0.01). Second, patients with chronic kidney disease, weight loss, liver disease, congestive heart failure, cerebrovascular disease, chronic obstructive pulmonary disease, metastatic cancer, and peripheral vascular disease had higher adjusted odds of AKI. Third, length of stay and cost of stay were significantly higher in patients who had AKI during the index admission. 

Conclusion

Patients with AKI had higher in-hospital mortality. We also report that at baseline, chronic kidney disease, weight loss, liver disease, congestive heart failure, cerebrovascular disease, chronic obstructive pulmonary disease, metastatic cancer, and peripheral vascular disease were important predictors of AKI in patients after TAVR. Length of stay and cost of stay were higher with AKI, which result in higher burden on the health care system due to increased resource utilization.

Predictors of Mortality in Patients With Transcatheter Aortic Valve Implantation: A National Inpatient Sample Database Analysis

Introduction

In recent decades, transcatheter aortic valve implantation (TAVI) has become a treatment of choice for aortic stenosis. The purpose of this study was to evaluate predictors of mortality in patients undergoing TAVI.

Methods

The National Inpatient Sample database from the year 2011 to 2018 was used to identify all patients undergoing TAVI during the study period.

Results

A total of 215,983 weighted hospitalizations for TAVI were included in the analysis. We report the following three main findings from our contemporary analysis of the NIS: (1) despite TAVI patients having a high comorbidity burden, mortality remains low at 2.2%, (2) in terms of baseline characteristics, end-stage renal disease, liver disease, congestive heart failure, chronic obstructive pulmonary disease, atrial fibrillation, and lung cancer remain significant predictors of mortality in patients undergoing TAVI, and (3) length of stay and cost of stay are significantly higher in patients who died during the hospitalization.

Conclusion

In conclusion, we report that at baseline, end-stage renal disease, liver disease, atrial fibrillation, and lung cancer are significant predictors of mortality in patients undergoing TAVI.

Transcatheter Aortic Valve Replacement Versus Surgical Aortic Valve Replacement: How Would You Manage This Patient With Severe Aortic Stenosis? : Grand Rounds Discussion From Beth Israel Deaconess Medical Center

Aortic stenosis (AS) is common, especially among the elderly. Left untreated, severe symptomatic AS is typically fatal. Surgical aortic valve replacement (SAVR) was the standard of care until transcatheter aortic valve replacement (TAVR) was shown to have lower mortality rates in patients at the highest surgical risk and was recommended for this group in the 2014 American Heart Association/American College of Cardiology (AHA/ACC) guidelines. In the 2017 AHA/ACC focused update, evidence of benefit and noninferiority extended the use of TAVR to intermediate-risk patients. More recent studies suggest potential benefit to low-risk patients, although no published guidelines yet recommend the use of TAVR for this population. An advantage of SAVR is a 30-year experience with valve durability, but SAVR may have higher rates of perioperative death and a slower return of quality of life. Although TAVR has less than 10-year experience with valve durability, it has lower or noninferior primary end points, such as mortality and stroke, and fewer periprocedural complications among anatomically permissive patients. Here, a cardiologist and a cardiothoracic surgeon debate the risks and benefits of TAVR versus SAVR for a patient with severe symptomatic AS who is at low risk for surgical death.

Recent trends in aortic valve interventions: Data of the Netherlands heart registration

BACKGROUND AND AIM OF THE STUDY

Transcatheter aortic valve implantation (TAVI) has evolved from bailout for inoperable patients to an alternative to surgical aortic valve replacement (SAVR) in higher-risk groups. The aim of this study is to describe these clinical trends in TAVI and SAVR in patients with aortic valve disease.

METHODS

We analyzed data of the Netherlands Heart Registration (NHR) up to 2018 to explore the trends in TAVI and SAVR among 14 cardiac centers in the Netherlands.

RESULTS

Between 2013 and 2017, a total of 7432 isolated SAVR and 5929 TAVI procedures have been performed. A 43.9% increase in the total number of procedures was observed, mainly due to the considerable increase in the number of TAVI procedures. In 2017, there was a decrease in the number of SAVR procedures. In the TAVI group, 30- and 120-day mortality decreased significantly from 7.2% and 10.6% in 2013 to 3.4% and 5.7% in 2017, respectively. In the SAVR group, 30- and 120-day mortality decreased from 1.7% and 2.9% in 2013 to 1.2% and 1.7% in 2017, respectively. Outcomes showed a significant decrease in vascular complications after TAVI. The risk profile of TAVI patients has changed over time.

CONCLUSIONS

The recent developments in TAVI have contributed to the increasing numbers of aortic valve interventions in the Netherlands. Mortality rates after SAVR and TAVI decreased as did the rate of complications after TAVI. Furthermore, a trend towards decrease of preoperative risk was observed.

Classification of Aortic Stenosis Before and After Transcatheter Aortic Valve Replacement Using Cardio-mechanical Modalities

This paper reports our study on the impact of transcatheter aortic valve replacement (TAVR) on the classification of aortic stenosis (AS) patients using cardio-mechanical modalities. Machine learning algorithms such as decision tree, random forest, and neural network were applied to conduct two tasks. Firstly, the pre- and post-TAVR data are evaluated with the classifiers trained in the literature. Secondly, new classifiers are trained to classify between pre- and post-TAVR data. Using analysis of variance, the features that are significantly different between pre- and post-TAVR patients are selected and compared to the features used in the pre-trained classifiers. The results suggest that pre-TAVR subjects could be classified as AS patients but post-TAVR could not be classified as healthy subjects. The features which differentiate pre- and post-TAVR patients reveal different distributions compared to the features that classify AS patients and healthy subjects. These results could guide future work in the classification of AS as well as the evaluation of the recovery status of patients after TAVR treatment.

Myval transcatheter heart valve system in the treatment of severe symptomatic aortic stenosis

The transcatheter aortic valve replacement (TAVR) is an established treatment for patients with severe symptomatic aortic stenosis (AS) at prohibitive risk for surgery. It is an alternative treatment to surgical aortic valve replacement in patients with AS at intermediate- and high-surgical risk. Although regulatory authorities extend the indications of TAVR to treat patients at low-surgical risk, the limitations of earlier-generation transcatheter heart valve (THV) systems accelerate the development of improved newer generation of THV systems. Myval™ THV (Meril Life Sciences Pvt. Ltd., Vapi, Gujarat, India) is a newer-generation, balloon-expandable TAVR system with features that facilitate accurate positioning of the bioprosthetic valve and favorable procedural and clinical outcomes. This review summarizes existing preclinical and clinical data on Myval THV for the intervention of symptomatic native AS and lays out the plan for future research program.

Use of Intracardiac Echocardiography to Differentiate Post–Transcatheter Aortic Valve Replacement Valve Insufficiency Masquerading as Paravalvular Leak

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TAVR has become a prevalent procedure.

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PVL is a complication of TAVR with increased risk for mortality.

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TEE, TTE, and angiography may misrepresent TAVR eccentric regurgitation for PVL.

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ICE may be used to distinguish TAVR regurgitation.

Ultrasound-Guided Percutaneous Balloon Aortic Valvuloplasty for Aortic Stenosis

Percutaneous balloon aortic valvuloplasty (PBAV), which is used to treat symptomatic aortic stenosis, requires ionizing radiation and contrast agent for imaging guidance. The aim of the study is to evaluate the feasibility and effectiveness of ultrasound-guided PBAV in patients with aortic stenosis. This case series included 30 patients (14 males; mean age, 61.5 ± 4.5 years) with moderate/severe aortic stenosis treated with ultrasound-guided PBAV at the Ultrasound Department, Fuwai Hospital, Beijing, China, between January 2016 and July 2019. Cardiac function (New York Heart Association grade) was assessed before PBAV and 1 month after the procedure. Aortic peak jet velocity, aortic valve orifice area (AVA), mean transvalvular pressure gradient (MTPG), left ventricular end-diastolic diameter (LVDD), left ventricular ejection fraction (LVEF), and left ventricular end-systolic diameter (LVESD) were determined before and immediately after PBAV using Doppler echocardiography. Preprocedural cardiac function was grade I in 3 cases, grade II in 9 cases, grade III in 10 cases, and grade IV in 8 cases. Postprocedural cardiac function was grade I in 22 cases, grade II in 4 cases, and grade III in 4 cases, suggesting that cardiac function was improved by PBAV. Ultrasound-guided PBAV resulted in significant improvements (P < 0.05) in aortic peak jet velocity (3.68 ± 0.811 m/s vs. 4.79 ± 0.63 m/s), MTPG (33.77 ± 13.85 mmHg vs. 54.54 ± 13.81 mmHg), AVA (1.96 ± 0.25 cm² vs. 0.98 ± 0.12 cm²), LVEDD (51.90 ± 3.21 mm vs. 65.60 ± 6.81 mm), LVEF (63.46 ± 11.29% vs. 56.31 ± 11.04%), and LVESD (35.50 2.62 mm vs. 45.20 ± 2.42 mm). Ultrasound-guided PBAV is feasible and achieves good short-term effects in patients with aortic stenosis.

Differential Leaflet Remodeling of Bone Marrow Cell Pre-Seeded Versus Nonseeded Bioresorbable Transcatheter Pulmonary Valve Replacements

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Bone marrow mononuclear cell pre-seeding of polycarbonate bisurea–based tissue-engineered heart valves has detrimental effects on long-term performance and in situ remodeling and, therefore, should be avoided.

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Leaflet-specific analysis revealed pronounced remodeling differences with regard to cell infiltration, scaffold resorption, and extracellular matrix deposition within the same valve explant.

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The heterogeneity in remodeling of polycarbonate bisurea–based tissue-engineered heart valves may have important safety implications in terms of clinical translation.

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An in-depth understanding of the mechanobiological mechanisms involved in the in situ remodeling is required to limit the risk of unpredictable (maladaptive) remodeling.

This study showed that bone marrow mononuclear cell pre-seeding had detrimental effects on functionality and in situ remodeling of bioresorbable bisurea-modified polycarbonate (PC-BU)-based tissue-engineered heart valves (TEHVs) used as transcatheter pulmonary valve replacement in sheep. We also showed heterogeneous valve and leaflet remodeling, which affects PC-BU TEHV safety, challenging their potential for clinical translation. We suggest that bone marrow mononuclear cell pre-seeding should not be used in combination with PC-BU TEHVs. A better understanding of cell–scaffold interaction and in situ remodeling processes is needed to improve transcatheter valve design and polymer absorption rates for a safe and clinically relevant translation of this approach.

TAVI and the future of aortic valve replacement

Aortic valve stenosis (AS) is the most common valvular pathology and has traditionally been managed using surgical aortic valve replacement (SAVR). A large proportion of affected patient demographics, however, are unfit to undergo major surgery given underlying comorbidities. Since its introduction in 2002, transcatheter aortic valve implantation (TAVI) has gained popularity and transformed the care available to different-risk group patients with severe symptomatic AS. Specific qualifying criteria and refinement of TAVI techniques are fundamental in determining successful outcomes for intervention. Given the successful applicability in high-risk patients, TAVI has been further developed and trialed in intermediate and low-risk patients. Within intermediate-risk patient groups, TAVI was shown to be noninferior to SAVR evaluating 30-d mortality and secondary endpoints such as the risk of bleeding, development of acute kidney injury, and length of admission. The feasibility of expanding TAVI procedures into low-risk patients is still a controversial topic in the literature. A number of trials have recently been published which demonstrate TAVI as noninferior and even superior over SAVR for primary study endpoints.

Preclinical Assessment of Cardiac Valve Substitutes: Current Status and Considerations for Engineered Tissue Heart Valves

Tissue engineered heart valve (TEHV) technology may overcome deficiencies of existing available heart valve substitutes. The pathway by which TEHVs will undergo development and regulatory approval has several challenges. In this communication, we review: (1) the regulatory framework for regulation of medical devices in general and substitute heart valves in particular; (2) the special challenges of preclinical testing using animal models for TEHV, emphasizing the International Standards Organization (ISO) guidelines in document 5840; and (3) considerations that suggest a translational roadmap to move TEHV forward from pre-clinical to clinical studies and clinical implementation.

Three-Dimensional Echocardiographic Imaging of a Gerbode Defect Complicating Transcatheter Aortic Valve Replacement

We describe a case of a 77-year-old male who underwent transcatheter aortic valve implantation (TAVR) with Edwards SAPIEN XT size 26 mm for severe aortic stenosis. Postprocedural transesophageal echocardiography (TEE) showed left-to-right shunt between the left ventricular outflow tract just below the bioprosthesis and the right atrium across the atrioventricular septum (Gerbode defect). Three-dimensional echocardiography (3DE) allowed a detailed anatomical imaging of the shape and the location of a small, circular, atrioventricular defect that was a type II, direct, supravalvular, Gerbode-type defect. This is the third report of a Gerbode defect after TAVR whose diagnosis has important implications on clinical decision-making. TEE plays a key role; its diagnostic ability is enriched by the additional value of 3DE.

A 3D Printed Aortic Arch Template to Facilitate Decision-Making Regarding the Use of an Externalized Transapical Wire during Thoracic Endovascular Aneurysm Repair

Thoracic endovascular aortic repair (TEVAR) is an established treatment option, although some anatomical challenges require a through-and-through wire technique, and subsequently transapical access via minithoracotomy can be required. It is clear that an objective tool to facilitate decision-making is needed. A 3D print of a severely angulated aortic arch was used as a template to advance a stent graft, and this was achieved after pulling the top of the wire. This simulation assisted in decision-making relating to transapical access with a wire externalization. A 3D aortic print could be used in advance to simulate the TEVAR procedure and facilitate any other decisions regarding additional transapical access.

Chest Radiographic Appearance of Minimally Invasive Cardiac Implants and Support Devices: What the Radiologist Needs to Know

Minimally invasive implantable cardiac devices used in valve repair and replacement, cardiovascular support, and partial chamber and appendageal occlusion represent a burgeoning area of both bioengineering and clinical innovation. In addition to familiarizing the reader with the radiographic appearance of the most commonly utilized and encountered newer devices, this review will also address the relevant clinical and pathophysiological indications for usage and deployment as well as potentially encountered complications.

Good enough…isn't

Mild PVR has been shown to increase all-cause and cardiovascular mortality after TAVR, especially in high surgical risk patients. Mechanistic and associative causes, as well imprecise ascertainment have been suggested as underlying etiologies of this association. Ongoing trials with newer valve technologies, broader patient inclusion and more systematic assessment of PVR may provide further insight into the prevalence, causality, and outcome of PVR.

Off-the-shelf tissue engineered heart valves for in situ regeneration: current state, challenges and future directions

INTRODUCTION

Transcatheter aortic valve replacement (TAVR) is continuously evolving and is expected to surpass surgical valve implantation in the near future. Combining durable valve substitutes with minimally invasive implantation techniques might increase the clinical relevance of this therapeutic option for younger patient populations. Tissue engineering offers the possibility to create tissue engineered heart valves (TEHVs) with regenerative and self-repair capacities which may overcome the pitfalls of current TAVR prostheses.

AREAS COVERED

This review focuses on off-the-shelf TEHVs which rely on a clinically-relevant in situ tissue engineering approach and which have already advanced into preclinical or first-in-human investigation.

EXPERT COMMENTARY

Among the off-the-shelf in situ TEHVs reported in literature, the vast majority covers pulmonary valve substitutes, and only few are combined with transcatheter implantation technologies. Hence, further innovations should include the development of transcatheter tissue engineered aortic valve substitutes, which would considerably increase the clinical relevance of such prostheses.