TAVI and the future of aortic valve replacement

Pathological Mechanism and Treatment of Calcified Aortic Stenosis

Calcified aortic stenosis (AS) is one of the most common valvular heart diseases worldwide, characterized by progressive fibrocalcific remodeling and thickening of the leaflets, which ultimately leads to obstruction of blood flow. Its pathobiology is an active and complicated process, involving endothelial cell dysfunction, lipoprotein deposition and oxidation, chronic inflammation, phenotypic transformation of valve interstitial cells, neovascularization, and intravalvular hemorrhage. To date, no targeted drug has been proven to slow down or prevent disease progression. Aortic valve replacement is still the optimal treatment of AS. This article reviews the etiology, diagnosis, and management of calcified aortic stenosis and proposes novel potential therapeutic targets.

One-year initial efficacy and safety outcomes of the premounted dry-pericardium Vienna self-expandable transcatheter aortic valve system: A first-in-human VIVA feasibility study

BACKGROUND

The dry-pericardium Vienna transcatheter aortic valve system is repositionable and retrievable, already premounted on the delivery system, eliminating the need for assembly and crimping of the device before valve implantation.

METHODS

The VIVA first-in-human feasibility study, a prospective, nonrandomized, single-center trial, evaluated the Vienna aortic valve in 10 patients with severe symptomatic aortic stenosis, who were at intermediate or high surgical risk. This study, registered at ClinicalTrials.gov (NCT04861805), focused on the safety, feasibility, clinical and hemodynamic performance of the Vienna system up to 1-year follow-up.

RESULTS

The mean patient age was 79 ± 5 years, 60% male. Valve sizes used: 26 mm (10%), 29 mm (30%), 31 mm (60%). Key hemodynamic improvements were significant: mean aortic valve pressure gradient (mmHg) decreased from 48.7 to 8.1, aortic valve area (cm2) increased from 0.75 to 1.91, and maximum jet velocity through the aortic valve (m/s) decreased from 4.41 to 1.95 (p < 0.0001). No moderate/severe paravalvular leakage was observed, and computed tomography scans revealed no evidence of hypo-attenuated leaflet thickening. The study recorded one life-threatening bleeding event, two cases requiring postprocedural pacemaker implantation, and three ischemic events, with only one causing lasting neurological impairment. Importantly, there were no cases of cardiovascular mortality and only one noncardiovascular death, which was confirmed as unrelated to the device.

CONCLUSIONS

The study indicates the Vienna valve as a potential option for severe symptomatic aortic stenosis, designed to streamline the procedure and potentially lower healthcare costs by reducing resource and equipment needs, also procedural errors. Further research is essential to thoroughly evaluate its safety and efficacy.

A Fibrin-Thrombin Based In Vitro Perfusion System to Study Flow-Related Prosthetic Heart Valves Thrombosis

Prosthetic heart valve (PHV) replacement has increased the survival rate and quality of life for heart valve-diseased patients. However, PHV thrombosis remains a critical problem associated with these procedures. To better understand the PHV flow-related thrombosis problem, appropriate experimental models need to be developed. In this study, we present an in vitro fibrin clot model that mimics clot accumulation in PHVs under relevant hydrodynamic conditions while allowing real-time imaging. We created 3D-printed mechanical aortic valve models that were inserted into a transparent glass aorta model and connected to a system that simulates human aortic flow pulse and pressures. Thrombin was gradually injected into a circulating fibrinogen solution to induce fibrin clot formation, and clot accumulation was quantified via image analysis. The results of valves positioned in a normal versus a tilted configuration showed that clot accumulation correlated with the local flow features and was mainly present in areas of low shear and high residence time, where recirculating flows are dominant, as supported by computational fluid dynamic simulations. Overall, our work suggests that the developed method may provide data on flow-related clot accumulation in PHVs and may contribute to exploring new approaches and valve designs to reduce valve thrombosis.

Extracellular Vesicles to Predict Outcomes After Transcatheter Aortic Valve Implantation - a Prospective, Multicenter Cohort Study

INTRODUCTION

Transcatheter aortic valve implantation (TAVI) is an established treatment for aortic stenosis (AS) in patients at intermediate and high surgical risk. Circulating extracellular vesicles (EVs) are nanoparticles involved in cardiovascular diseases. We aimed to (i) determine the effect of TAVI on plasma concentrations of five EV subtypes and (ii) evaluate the predictive value of EVs for post-TAVI outcomes.

METHODS

Blood samples were collected 1 day before TAVI and at hospital discharge. Concentrations of EVs were evaluated using flow cytometry.

RESULTS

Concentration of leukocytes EVs decreased after TAVI, compared to the measurement before (p = 0.008). Among 123 patients discharged from the hospital, 19.5% experienced MACCE during the median of 10.3 months. Increased pre-TAVI concentration of phosphatidylserine-exposing EVs was an independent predictor of MACCE in multivariable analysis (OR 5.313, 95% CI 1.164-24.258, p = 0.031).

CONCLUSIONS

Patients with increased pre-TAVI concentration of procoagulant, PS-exposing EVs have over fivefold higher odds of adverse outcomes.

Assessment of transabdominal fat volumes as a predictor of prognosis in patients undergoing transcatheter aortic valve replacement

Transcatheter aortic valve replacement (TAVR) has emerged as a well-established treatment option for eligible patients with severe aortic stenosis. This study aimed to investigate the correlation between abdominal fat tissue volumes, measured using computed tomography (CT), and all-cause mortality in patients undergoing TAVR. The study included 258 consecutive patients who underwent TAVR at a single center between September 2017 and November 2020. During the preoperative preparation, CT scans were used to perform a semi-quantitative measurement of abdominal fat components. Body mass index (BMI) for each participant was calculated. The relationship between fat parameters and overall survival was determined using multivariable Cox proportional hazards models. Participants had a mean age of 76.8 ± 7.8 years, of whom 32.9% were male. The median follow-up period was 12 months, during which 38 patients (14.7%) died. Both the survivor and non-survivor groups showed comparable risk factors. Regarding transabdominal fat volume parameters, deceased individuals exhibited significantly lower values. However, no significant differences were observed in BMI and transabdominal area measurements. Among transabdominal fat parameters, only subcutaneous fat volume [adjusted Hazard Ratio (aHR) = 0.83, p = 0.045] and total fat volume (TFV) [aHR = 0.82, p = 0.007] were identified as significant predictors of reduced all-cause mortality. Furthermore, TFV demonstrated the highest discriminative performance with a threshold of ≤ 9.1 L (AUC = 0.751, p < 0.001, sensitivity 71.1%, specificity 70.9%). Preoperative CT-based abdominal fat volume parameters, particularly TFV, can serve as potential predictors of survival in patients undergoing TAVR.

Insights into microorganisms, associated factors, and the oral microbiome in infective endocarditis patients

Introduction

Infective Endocarditis (IE) is a rare, life-threatening infection of the endocardium with multisystem effects. Culprit microorganisms derived from different niches circulate through the bloodstream and attach to the endocardium, particularly the heart valves. This study aimed to investigate culprit microorganisms among a cross-sectional cohort of IE patients, their associated factors, and to explore the potential relationship to the oral microbiome.

Methods

In this observational study, we undertook a cross-sectional analysis of 392 medical records from patients diagnosed with IE. The primary outcome of this study was to analyse the association between the IE culprit microorganisms and the underlying anatomical types of IE (native valve (NVE), prosthetic valve (PVE), or cardiac device-related (CDE)). Secondary outcomes encompassed a comparative analysis of additional factors, including: the treatment approaches for IE, and the categorisation of blood cultures, extending to both genus and species levels. Additionally, we cross-referenced and compared the species-level identification of IE bacteraemia outcome measures with data from the expanded Human Oral Microbiome Database (eHOMD).

Results

A culprit microorganism was identified in 299 (76.28%) case participants. Staphylococcal infections were the most common (p < 0.001), responsible for 130 (33.16%) hospitalisations. There were 277 (70.66%) cases of NVE, 104 (26.53%) cases of PVE, and 11 (2.81%) cases of CDE. The majority of PVE occurred on prosthetic aortic valves (78/104, 75%), of which 72 (93.5%) were surgical aortic valve replacements (SAVR), 6 (7.8%) were transcatheter aortic valve implants, and one transcatheter pulmonary valve implant. Overall, underlying anatomy (p = 0.042) as well as the treatment approaches for IE (p < 0.001) were significantly associated with IE culprit microorganisms. Cross-reference between IE bacteraemia outcomes with the eHOMD was observed in 267/392 (68.11%) cases.

Conclusions

This study demonstrated that IE patients with a history of stroke, smoking, intravenous drug use, or dialysis were more likely to be infected with Staphylococcus aureus. CDE case participants and patients who had previous SAVR were most associated with Staphylococcus epidermidis. IE patients aged 78+ were more likely to develop enterococci IE than other age groups. Oral microorganisms indicated by the eHOMD are significantly observed in the IE population. Further research, through enhanced dental and medical collaboration, is required to correlate the presence of oral microbiota as causative factor for IE.

Nondual Antiplatelet Therapy Versus Dual Antiplatelet Therapy Before Transcatheter Aortic Valve Replacement: A Systematic Review and Meta-analysis

ABSTRACT

Transcatheter aortic valve replacement (TAVR) is an interventional procedure performed in patients with severe aortic stenosis and often required perioperative antiplatelet therapy. Most previous studies have focused on antiplatelet therapy following TAVR. However, few studies have investigated the prognostic effect of preoperative antiplatelet therapy in patients undergoing TAVR. This study aimed to compare the efficacy and safety of nondual antiplatelet therapy (non-DAPT) and DAPT before TAVR. We performed a systematic search of Embase, PubMed, and Web of Science until February 2023. Studies were eligible if they compared non-DAPT (single antiplatelet therapy or no antiplatelet therapy) with DAPT in patients before TAVR. A total of 5 studies, including 2329 patients, met the inclusion criteria and were included in the meta-analysis. Preoperative non-DAPT significantly decreased minor bleeding events compared with preoperative DAPT [odds ratio 0.58; 95% confidence interval: 0.44-0.76]. There were no significant differences in the incidence of other bleeding events, transfusions, stroke, myocardial infarction, or all-cause death. Preoperative single antiplatelet therapy significantly decreased the incidence of major bleeding compared with DAPT (odds ratio 0.14; 95% confidence interval: 0.04-0.48). Preoperative non-DAPT significantly reduced minor bleeding events in patients undergoing TAVR, without increasing the risk of stroke and myocardial infarction.

Pacemaker dependency and conduction system recovery following transcatheter aortic valve implantation

BACKGROUND

Transcatheter aortic valve implantation (TAVI)-related conduction system disorders are dynamic and may resolve over time. The purpose of this study was to investigate predictive factors of PM dependency among patients receiving permanent PM implantation after TAVI.

METHODS

We included 37 consecutive patients who underwent PPM implantation within six days after TAVI and who completed a 12-month follow-up. Patients were divided into two groups according to PPM dependency at follow-up: PPM-dependent group and non-PPM-dependent group. Device follow-ups were performed at one, six and 12 months.

RESULTS

There were no significant differences in either baseline clinical characteristics or procedural data and results. Analysis of baseline ECGs showed a statistical difference in PR interval (200.1±17.2 ms in the PPM-dependent group vs. 175±23.3 ms in the non PPM-dependent group [P=0,003]) and in the presence of RBBB (four patients in the PPM-dependent group vs. no patients in the non PPM-dependent group [P=0.02]) as well as QRS duration (117.3±27.4 ms in the PPM-dependent group and 99±18.3 msec in the non PPM-dependent group [P=0.04]).

CONCLUSIONS

The rate of PPM dependency was significantly reduced at 12-month follow-up: from 62,2% at the time of implantation to 35,1%. PR interval and RBBB were the most important predictive factors for PPM dependency. Persistent AVB and alternating BBB were prevalent in the PPM-dependent group. In the absence of persistent AVB or alternating BBB, we suggest that patients without long PR interval and RBBB at baseline ECG be carefully evaluated before permanent PM implantation, as conduction system recovery is possible.

Pre-TAVI imaging: an Italian survey by the CT PRotocol optimization (CT-PRO) group

PURPOSE

The purpose of this survey was to evaluate the current state-of-art of pre-TAVI imaging in a large radiological professional community.

METHODS

Between December 2022 and January 2023 all members of the Italian Society of Medical and Interventional Radiology (SIRM) were invited by the CT PRotocol Optimization group (CT-PRO group) to complete an online 24-item questionnaire about pre-TAVI imaging.

RESULTS

557 SIRM members participated in the survey. The greatest part of respondents were consultant radiologists employed in public hospitals and 84% claimed to routinely perform pre-TAVI imaging at their institutions. The most widespread acquisition protocol consisted of an ECG-gated CT angiography (CTA) scan of the aortic root and heart followed by a non-ECG-synchronized CTA of the thorax, abdomen, and pelvis. Contrast agent administration was generally tailored on the patient's body weight with a preference for using high concentration contrast media. The reports were commonly written by radiologists with expertise in cardiovascular imaging, and included all the measurements suggested by current guidelines for adequate pre-procedural planning. About 60% of the subjects affirmed that the Heart Team is present at their institutions, however only 7% of the respondents regularly attended the multidisciplinary meetings.

CONCLUSIONS

This survey defines the current pre-TAVI imaging practice in a large radiological professional community. Interestingly, despite the majority of radiologists follow the current guidelines regarding acquisition and reporting of pre-TAVI imaging studies, there is still a noteworthy absence from multidisciplinary meetings and from the Heart Team.

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.

Local versus General Anaesthesia for Transcatheter Aortic Valve Implantation (TAVI): A Systematic Review, Meta-Analysis, and Trial Sequential Analysis of Randomised and Propensity-Score Matched Studies

Transcatheter aortic valve implantation (TAVI) is a common practice for severe aortic stenosis, but the choice between general (GA) and local anesthesia (LA) remains uncertain. We conducted a comprehensive literature review until April 2023, comparing the safety and efficacy of LA versus GA in TAVI procedures. Our findings indicate significant advantages of LA, including lower 30-day mortality rates (RR: 0.69; 95% CI [0.58, 0.82]; p < 0.001), shorter in-hospital stays (mean difference: -0.91 days; 95% CI [-1.63, -0.20]; p = 0.01), reduced bleeding/transfusion incidents (RR: 0.64; 95% CI [0.48, 0.85]; p < 0.01), and fewer respiratory complications (RR: 0.56; 95% CI [0.42, 0.76], p<0.01). Other operative outcomes were comparable. Our findings reinforce prior evidence, presenting a compelling case for LA's safety and efficacy. While patient preferences and clinical nuances must be considered, our study propels the discourse towards a more informed anaesthesia approach for TAVI procedures.

Cerebral regional oxygen saturation as a predictive parameter for preoperative heart failure and delayed hemodynamic recovery in transcutaneous aortic valve implantation: a retrospective cohort study

This study aimed to investigate the relationship of perioperative cerebral regional oxygen saturation (rSO2) with various preoperative clinical variables and hemodynamic changes during transfemoral transcatheter aortic valve implantation (TAVI) under general anesthesia. We retrospectively analyzed cerebral rSO2 values from left-hemisphere measurements obtained using near-infrared spectroscopy (O3™ regional oximetry) at five time points: pre-induction, the start of the procedure, the start of valve deployment, time of lowest cerebral rSO2 value during valve deployment, and the end of the procedure. This study included 91 patients (60 with balloon-expandable valves and 31 with self-expandable valves). The baseline cerebral rSO2 values were correlated with B-type natriuretic peptide, hemoglobin, fractional shortening, ejection fraction, left ventricular mass index, left ventricular end-systolic diameter, STS risk of mortality, and STS morbidity or mortality. The patients who took longer to recover their systolic blood pressure to 90 mmHg after valve deployment with a balloon-expandable valve (group B) had lower cerebral rSO2 values during deployment compared to patients with faster recovery with balloon-expandable valve (group A) and with self-expandable valve (group C). Baseline cerebral rSO2 is associated with preoperative variables related to cardiac failure and function, and a significant decline during valve deployment may indicate a risk of prolonged hypotension during TAVI.

Lifetime Management of Patients With Severe Aortic Stenosis in the Era of Transcatheter Aortic Valve Replacement

Aortic stenosis is the most common valvular disease. Surgical aortic valve replacement (SAVR) using mechanical valves has been the preferred treatment for younger patients, but bioprosthetic valves are gaining favour to avoid anticoagulation with warfarin. Transcatheter aortic valve replacement (TAVR) was approved in recent years for the treatment of severe aortic stenosis in intermediate- and low-risk patients as an alternative to SAVR. The longer life expectancy of these groups of patients might exceed the durability of the TAVR or SAVR bioprosthetic valves. Therefore, many patients need 2 or even 3 interventions during their lifetime. Because it has important implications on the feasibility of subsequent procedures, the decision between opting for SAVR or TAVR as the primary procedure requires thorough consideration by the heart team, incorporating patient preferences, clinical indicators, and anatomic aspects. If TAVR is favoured initially, selecting the valve type and determining the implantation level should be conducted, aiming for positive outcomes in the index intervention and keeping in mind the potential for subsequent TAVR-in-TAVR procedures. When SAVR is selected as the primary procedure, the operator must make choices regarding the valve type and the potential need for aortic root enlargement, with the intention of facilitating future valve-in-valve interventions. This narrative review examines the existing evidence concerning the lifelong management of severe aortic stenosis, delving into available treatment strategies, particularly emphasising the initial procedure's selection and its impact on subsequent interventions.

A Case Report of a Pericapsular Nerve Group Block for Transcatheter Aortic Valve Implantation

A pericapsular nerve group (PENG) block is an interfascial plane block that targets the articular branches of the femoral and obturator nerves. PENG blocks may be used for hip, vein, and groin surgeries. Transcatheter aortic valve implantation (TAVI) is a common treatment for aortic valve stenosis (AVS). Patients who undergo TAVI tend to be at high risk due to their older age and comorbidities. A PENG block using a high volume of local anesthetics may be as effective as a lumbar plexus block. In this case report, we describe successful anesthesia management using PENG blocks in 2 patients who underwent TAVI.

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.

Association of general anesthesia exposure with risk of postoperative delirium in patients receiving transcatheter aortic valve replacement: a meta-analysis and systematic review

The aim of this meta-analysis was to assess the association of general anesthesia (GA) exposure with the risk of POD in this patient population. Databases including Medline, EMBASE, Cochrane library, and Google Scholar were searched from inception to December 2022. Analysis of 17 studies published between 2015 and 2021 involving 10,678 individuals revealed an association of GA exposure with an elevated risk of POD [odd ratio (OR) = 1.846, 95% CI 1.329 to 2.563, p = 0.0003, I2 = 68.4%, 10,678 patients]. Subgroup analysis of the diagnostic methods also demonstrated a positive correlation between GA exposure and POD risk when validated methods were used for POD diagnosis (OR = 2.199, 95% CI 1.46 to 3.31, p = 0.0002). Meta-regression analyses showed no significant impact of age, male proportion, and sample size on the correlation between GA and the risk of POD. The reported overall incidence of POD from the included studies regardless of the type of anesthesia was between 0.8 and 27%. Our meta-analysis showed a pooled incidence of 10.3% (95% CI 7% to 15%). This meta-analysis suggested an association of general anesthesia with an elevated risk of postoperative delirium, implying the necessity of implementing appropriate prophylactic strategies against this complication when general anesthesia was used in this clinical setting.

High-flow nasal oxygen vs. standard oxygen therapy for patients undergoing transcatheter aortic valve replacement with conscious sedation: a randomised controlled trial

BACKGROUND

Minimally invasive surgery is becoming more common and transfemoral transcatheter aortic valve replacement is offered to older patients with multiple comorbidities. Sternotomy is not required but patients must lie flat and still for up to 2-3 h. This procedure is increasingly being performed under conscious sedation with supplementary oxygen, but hypoxia and agitation are commonly observed.

METHODS

In this randomised controlled trial, we hypothesised that high-flow nasal oxygen would provide superior oxygenation as compared with our standard practice, 2 l min^-1 oxygen by dry nasal specs. This was administered using the Optiflow THRIVE Nasal High Flow delivery system (Fisher and Paykel, Auckland, New Zealand) at a flow rate of 50 l min^-1 and FiO₂ 0.3. The primary endpoint was the change in arterial partial pressure of oxygen (pO₂) during the procedure. Secondary outcomes included the incidence of oxygen desaturation, airway interventions, the number of times the patient reached for the oxygen delivery device, incidence of cerebral desaturation, peri-operative oxygen therapy duration, hospital length of stay and patient satisfaction scores.

RESULTS

A total of 72 patients were recruited. There was no difference in change in pO₂ from baseline using high-flow compared with standard oxygen therapy: median [IQR] increase from 12.10 (10.05-15.22 [7.2-29.8]) to 13.69 (10.85-18.38 [8.5-32.3]) kPa vs. decrease from 15.45 (12.17-19.33 [9.2-22.8]) to 14.20 (11.80-19.40 [9.7-35.1]) kPa, respectively. The percentage change in pO2 after 30 min was also not significantly different between the two groups (p = 0.171). There was a lower incidence of oxygen desaturation in the high-flow group (p = 0.027). Patients in the high-flow group assigned a significantly higher comfort score to their treatment (p ≤ 0.001).

CONCLUSION

This study has demonstrated that high flow, compared with standard oxygen therapy, does not improve arterial oxygenation over the course of the procedure. There are suggestions that it may improve the secondary outcomes studied.

TRIAL REGISTRATION

International Standard Randomised Controlled Trial Number (ISRCTN) 13,804,861. Registered on 15 April 2019. https://doi.org/10.1186/ISRCTN13804861.

Pathophysiology, emerging techniques for the assessment and novel treatment of aortic stenosis

Our perspectives on aortic stenosis (AS) are changing. Evolving from the traditional thought of a passive degenerative disease, developing a greater understanding of the condition's mechanistic underpinning has shifted the paradigm to an active disease process. This advancement from the 'wear and tear' model is a result of the growing economic and health burden of AS, particularly within industrialised countries, prompting further research. The pathophysiology of calcific AS (CAS) is complex, yet can be characterised similarly to that of atherosclerosis. Progressive remodelling involves lipid-protein complexes, with lipoprotein(a) being of particular interest for diagnostics and potential future treatment options.There is an unmet clinical need for asymptomatic patient management; no pharmacotherapies are proven to slow progression and intervention timing varies. Novel approaches are developing to address this through: (1) screening with circulating biomarkers; (2) development of drugs to slow disease progression and (3) early valve intervention guided by medical imaging. Existing biomarkers (troponin and brain natriuretic peptide) are non-specific, but cost-effective predictors of ventricular dysfunction. In addition, their integration with cardiovascular MRI can provide accurate risk stratification, aiding aortic valve replacement decision making. Currently, invasive intervention is the only treatment for AS. In comparison, the development of lipoprotein(a) lowering therapies could provide an alternative; slowing progression of CAS, preventing left ventricular dysfunction and reducing reliance on surgical intervention.The landscape of AS management is rapidly evolving. This review outlines current understanding of the pathophysiology of AS, its management and future perspectives for the condition's assessment and treatment.

Impact of nickel-titanium super-elastic material properties on the mechanical performance of self-expandable transcatheter aortic valves

Self-expandable transcatheter aortic valves (TAVs) elastically resume their initial shape when implanted without the need for balloon inflation by virtue of the nickel-titanium (NiTi) frame super-elastic properties. Experimental findings suggest that NiTi mechanical properties can vary markedly because of a strong dependence on the chemical composition and processing operations. In this context, this study presents a computational framework to investigate the impact of the NiTi super-elastic material properties on the TAV mechanical performance. Finite element (FE) analyses of TAV implantation were performed considering two different TAV frames and three idealized aortic root anatomies, evaluating the device mechanical response in terms of pullout force magnitude exerted by the TAV frame and peak maximum principal stress within the aortic root. The widely adopted NiTi constitute model by Auricchio and Taylor (1997) was used. A multi-parametric sensitivity analysis and a multi-objective optimization of the TAV mechanical performance were conducted in relation to the parameters of the NiTi constitutive model. The results highlighted that: five NiTi material model parameters (E_A, σ_tL^S, σ_tU^S, σ_tU^E and σ_cL^S) are significantly correlated with the FE outputs; the TAV frame geometry and aortic root anatomy have a marginal effect on the level of influence of each NiTi material parameter; NiTi alloy candidates with pareto-optimal characteristics in terms of TAV mechanical performance can be successfully identified. In conclusion, the proposed computational framework supports the TAV design phase, providing information on the relationship between the super-elastic behavior of the supplied NiTi alloys and the device mechanical response.

Quantification of paravalvular leaks associated with TAVI implants using 4D MRI in an aortic root phantom made possible by the use of 3D printing

Introduction

Transcatheter aortic valve implantation (TAVI) has become an alternative to surgical replacement of the aortic valve elderly patients. However, TAVI patients may suffer from paravalvular leaks (PVL). Detecting and grading is usually done by echocardiography, but is limited by resolution, 2D visualization and operator dependency. 4D flow magnetic resonance imaging (MRI) is a promising alternative, which did not reach clinical application in TAVI patients. The aim of this study was applying 3D printing technologies in order to evaluate flow patterns and hemodynamics of PVLs following TAVI, exploiting 4D flow MRI and standard ultrasound.

Materials and methods

An MR-compatible, anatomically left ventricle, aortic root, and ascending aorta model was fabricated by combining 3D-printed parts and various soft silicone materials to match physiological characteristics. An Abbott Portico™ valve was used in continuous antegrade flow (12-22 l/min), retrograde flow with varying transvalvular pressures (60-110 mmHg), and physiological pulsatile hemodynamics (aortic pressure: 120/80 mmHg, cardiac output: 5 l/min) Time-resolved MR measurements were performed above and below the TAVI stent and compared with color Doppler ultrasound measurements in exactly the same setup.

Results

The continuous antegrade flow measurements from MRI largely agreed with the flowmeter measurements, and a maximum error of only 7% was observed. In the retrograde configuration, visualization of the paravalvular leaks was possible from the MR measurements, but flow was overestimated by up to 33%. The 4D MRI measurement in the pulsatile setup revealed a single main PVL, which was also confirmed by the color Doppler measurements, and velocities were similar (2.0 m/s vs. 1.7 m/s).

Discussion

4D MRI techniques were used to qualitatively assess flow in a patient-specific, MR-compatible and flexible model, which only became possible through the use of 3D printing techniques. Flow patterns in the ascending aorta, identification and quantification of PVLs was possible and the location and extent of PVLs were confirmed by ultrasound measurements. The 4D MRI flow technique allowed evaluation of flow patterns in the ascending aorta and the left ventricle below the TAVI stent with good results in identifying PVLs, demonstrating its capabilities over ultrasound by providing the ability to visualize the paravalvular jets in three dimensions at however, additional expenditure of time and money.

Accelerating Digitalization in Healthcare with the InSilicoTrials Cloud-Based Platform: Four Use Cases

The use of in silico trials is expected to play an increasingly important role in the development and regulatory evaluation of new medical products. Among the advantages that in silico approaches offer, is that they permit testing of drug candidates and new medical devices using virtual patients or computational emulations of preclinical experiments, allowing to refine, reduce or even replace time-consuming and costly benchtop/in vitro/ex vivo experiments as well as the involvement of animals and humans in in vivo studies. To facilitate and widen the adoption of in silico trials, InSilicoTrials Technologies has developed a cloud-based platform, hosting healthcare simulation tools for different bench, preclinical and clinical evaluations, and for diverse disease areas. This paper discusses four use cases of in silico trials performed using the InSilicoTrials.com platform. The first application illustrates how in silico approaches can improve the early preclinical assessment of drug-induced cardiotoxicity risks. The second use case is a virtual reproduction of a bench test for the safety assessment of transcatheter heart valve substitutes. The third and fourth use cases are examples of virtual patients generation to evaluate treatment effects in multiple sclerosis and prostate cancer patients, respectively.

Predictors Of Post-Operative Negative Outcomes in Patients Undergoing Transcatheter Aortic Valve Implantation

With the advent of Transcatheter Aortic Valve Implantation (TAVI), populations who were previously not fit enough for heart valve surgery are now able to have a valve replacement without placing these higher risk individuals through major surgery. Complication rates following TAVI have reduced over the last few years, but recent studies suggest that the incidence of several complications remains high. Avoiding complications is key to reducing costs associated with TAVI, which is important given that the procedure is already more expensive than other treatment options. An emerging strategy for patients undergoing TAVI is to identify pre-operative factors predictive of post-operative adverse outcomes. This commentary summarises three systematic reviews exploring moderating factors for adverse events after TAVI surgery, with the aim of identifying statistically and clinically significant factors associated with poor surgical outcomes and contextualise these factors within clinical practice.

Prognostic value of ventricular longitudinal strain in patients undergoing transcatheter aortic valve replacement: A systematic review and meta-analysis

Introduction

Strain obtained by speckle tracking echocardiography (STE) can detect subclinical myocardial impairment due to myocardial fibrosis (MF) and is considered a prognostic marker. Aortic stenosis (AS) is not only a valve disease, but also a cardiomyopathy characterized by MF. The purpose of this study was to systematically review and analyze ventricular strain as a predictor of adverse outcomes in patients with AS undergoing transcatheter aortic valve replacement (TAVR).

Methods

PubMed, Embase, and the Cochrane library were searched for studies that investigated the prognostic value of impaired ventricular strain on patients with AS undergoing TAVR with all-cause mortality (ACM) and major adverse cardiovascular events (MACE). Pooled odds ratios (ORs), hazard ratios (HRs), and 95% confidence intervals (CIs) were calculated to assess the role of left (LVLS) and right (RVLS) ventricular longitudinal strain in the prognostic prediction of patients with AS undergoing TAVR. Sensitivity and subgroup analysis was performed to assess heterogeneity.

Results

Twelve studies were retrieved from 571 citations for analysis. In total, 1,489 patients with a mean age of 82 years and follow-up periods varying between 1 year and 8.5 years were included. Meta-analysis showed the impaired LVLS from eight studies was associated with an increased risk for combined ACM and MACE (OR: 1.08, 95% CI: 1–1.16; p = 0.037), and ACM alone (HR: 1.08, 95% CI: 1.01–1.16; p = 0.032). Impaired RVLS from four studies was associated with an increased risk of combined ACM and MACE (OR: 1.08, 95% CI: 1.02–1.14; p < 0.01), and ACM alone (HR: 1.07, 95% CI: 1.02–1.12; p < 0.01).

Conclusions

This meta-analysis demonstrated that ventricular strain, including LVLS and RVLS, had a substantial prognostic value in ACM or combined ACM and MACE, which could be used as a valid marker for risk stratification in patients with AS undergoing TAVR.

Understanding stage of innovation of invasive procedures and devices: protocol for a systematic review and thematic analysis

INTRODUCTION

Surgical innovation has generally occurred in an unstandardised manner. This has led to unnecessary exposure of patients to harm, research waste and inadequate evidence. The IDEAL (Idea, Development, Exploration, Assessment, Long-term follow-up) Collaboration provided a set of recommendations for evaluating surgical innovations based on their stage of innovation. Despite further refinements and guidance, adoption of the IDEAL recommendations has been slow; an important reason may be that determining the stage of innovation is often difficult. To facilitate evaluation of surgical innovations, there is a need for a detailed insight into what stage of innovation means, and how it can be determined. The aim of this study is to understand the concept of stage of innovation as reported in the literature.

METHODS AND ANALYSIS

A systematic review is being conducted. Ovid MEDLINE and Embase databases were searched from their inception until July 2021 using an iteratively developed strategy based on the concepts of stage of innovation, invasive procedures or devices and guidance. Articles were included if they described an approach to evaluating surgical innovations in stages, described a method for determining stage of innovation, described indicators of stage of innovation, defined stages or described potential sources of stage-related information. Conference abstracts and non-English language articles were excluded. Other articles were detected from citations within included articles and suggestions from experts in surgical innovation. Data will be extracted regarding approaches to evaluating surgical innovations, methods for determining stage of innovation, indicators of stage of innovation, definitions of stages and potential sources of stage-related information. A thematic analysis will be conducted, and findings summarised in a narrative report.

ETHICS AND DISSEMINATION

Ethical approval will not be required. This systematic review will be published in a peer-reviewed journal and presented at appropriate conferences.

PROSPERO REGISTRATION NUMBER

CRD42021270812.

Recent Advances in the Rheumatic Fever and Rheumatic Heart Disease Continuum

Nearly a century after rheumatic fever (RF) and rheumatic heart disease (RHD) was eradicated from the developed world, the disease remains endemic in many low- and middle-income countries (LMICs), with grim health and socioeconomic impacts. The neglect of RHD which persisted for a semi-centennial was further driven by competing infectious diseases, particularly the human immunodeficiency virus (HIV) pandemic. However, over the last two-decades, slowly at first but with building momentum, there has been a resurgence of interest in RF/RHD. In this narrative review, we present the advances that have been made in the RF/RHD continuum over the past two decades since the re-awakening of interest, with a more concise focus on the last decade’s achievements. Such primary advances include understanding the genetic predisposition to RHD, group A Streptococcus (GAS) vaccine development, and improved diagnostic strategies for GAS pharyngitis. Echocardiographic screening for RHD has been a major advance which has unearthed the prevailing high burden of RHD and the recent demonstration of benefit of secondary antibiotic prophylaxis on halting progression of latent RHD is a major step forward. Multiple befitting advances in tertiary management of RHD have also been realized. Finally, we summarize the research gaps and provide illumination on profitable future directions towards global eradication of RHD.

The JenaValve pericardial transcatheter aortic valve replacement system to treat aortic valve disease

Transcatheter aortic valve replacement is a valuable alternative technique to surgery and the spectrum of therapy continues to evolve. The JenaValve Pericaridal transcatheter aortic valve replacement System allows prosthesis fixation in a native, noncalcified aortic annulus with a unique paper clip-like anchorage mechanism. The low rate of paravalvular leakage and permanent pacemaker implantation emphasizes the further widespread use of the JenaValve - despite the limited data available. In May 2021, a CE mark for the transfemoral implantation in both aortic regurgitation and aortic stenosis was granted. However, no data have been published so far. The ongoing ALIGN trials are expected to provide the pending long-term data.

MitraClip for mitral valve regurgitation and transcatheter aortic valve implantation for severe aortic valve stenosis: state-of-the-art

There is a worldwide expansion in percutaneous therapy for valvular heart disease. Rapidly evolving technology and the general increase in life expectancy will support the evolution of new treatment options dedicated to structural heart interventions. Transcatheter aortic valve implantation for severe aortic valve stenosis and percutaneous mitral valve repair with the MitraClip system for severe mitral regurgitation have been demonstrated as a feasible, innovative alternative for surgical treatment. Despite the inequality in clinical experience, both procedures have encouraging results and now are a part of everyday clinical practice. More importantly, rapid development is expected in the next decades. However, the global coronavirus disease 2019 (COVID-19) pandemic imposed redistribution of healthcare resources. Hospitals were obliged to modify their workflow and limit TAVI and MitraClip procedures to urgent or in highly symptomatic patients. Despite this encumbrance improvement in technology and experience supported by robust evidence from current studies might extend indications for both procedures. The future holds promise for this treatment modality to become the preferred procedure for all patients despite age or risk and reserving surgical treatment for a minority. Thus, we present state-of-the-art and current evidence for both methods assumed to change the paradigm of treatment of valvular heart failure in the future.

Trans-apical aortic valve implantation for quadricuspid aortic valve with aortic regurgitation using J-valve system: a case reports

Background

Quadricuspid aortic valve (QAV) is a rare congenital heart defect usually accompanied with different hemodynamic abnormalities. Due to the rarity of QAV, treatment and prognosis of QAV patients with aortic regurgitation still remain challenging. We here present the first case of a patient with severe QAV regurgitation who underwent successful treatment and performed favorable prognosis with transapical aortic valve implantation (TAVI) using J-Valve system.

Case presentation

A 62-year-old man experienced intermittent palpitation, shortness of breath and chest pain. Echocardiography revealed congenital QAV with massive aortic regurgitation and mild aortic stenosis, left ventricular enlargement. Aortic valve replacement was successfully performed with TAVI using J-Valve system. The postoperation and follow-up was uneventful.

Conclusion

TAVI using J-Valve system has emerged as a new high success rate method for treatment of patients with simple non-calcified aortic valve insufficiency.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13019-021-01586-9.

Prognosis and outcome determinants after heart failure diagnosis in patients who underwent aortic valvular intervention

AIMS

To study clinical phenotype, prognosis for all-cause and cardiovascular (CV) mortality and predictive factors in patients with incident heart failure (HF) after aortic valvular intervention (AVI) for aortic stenosis (AS).

METHODS AND RESULTS

In this retrospective, observational study we included patients from the Swedish Heart Failure Registry (SwedeHF) recorded 2003-2016, with AS diagnosis and AVI before HF diagnosis. The AS diagnosis was established according to International Classification of Diseases 10th revision (ICD-10) codes, thus without information concerning clinical or echocardiographical data on the aortic valve disease. The patients were divided into two subgroups: left ventricular ejection fraction (LVEF) ≥ 50% (AS-HFpEF) and <50% (AS-HFrEF). We individually matched three controls with HF from the SwedeHF without AS (control group) for each patient. Baseline characteristics, co-morbidities, survival status and outcomes were obtained by linking the SwedeHF with two other Swedish registries. We used Kaplan-Meier curves to present time to all-cause mortality, cumulative incidence function for time to CV mortality and Cox proportional hazards model to evaluate the relative difference between AS-HFrEF and AS-HFpEF and AS-HF and controls. The crude all-cause mortality was 49.0%, CV mortality 27.9% in AS-HF patients, respectively 44.7% and 26.6% in matched controls. The adjusted risk for all-cause mortality and CV mortality was similar in HF, regardless of LVEF vs. controls. No significant difference in factors predicting higher all-cause mortality was observed in AS-HFrEF vs. AS-HFpEF, except for diabetes (only in AS-HFrEF), with statistically significant interaction predicting death between the two groups.

CONCLUSIONS

In this nationwide SwedeHF study, we characterized incident HF population after AVI. We found no significant differences in all-cause and CV mortality compared with general HF population. They had virtually the same predictors for mortality, regardless of LVEF.

Correlation Between Plasma Matrix Metalloproteinase-28 Levels and Severity of Calcific Aortic Valve Stenosis

BACKGROUND Calcific aortic valve disease is a common cardiovascular disorder worldwide. This study aimed to investigate the correlation between plasma matrix metalloproteinase-28 (MMP-28) levels and the severity of calcific aortic valve stenosis. MATERIAL AND METHODS Calcific aortic valve stenosis patients who were admitted to the heart center of our hospital between January 2016 and January 2019 to undergo surgery were successively enrolled in this study (55 males and 24 females with an average age of 58.5±9.6). Information on echocardiography, plasma MMP-28 levels, and other clinical data of the patients was retrospectively collected. RESULTS The average plasma MMP-28 level was 2.43±2.22 ng/mL (range, 0.22-8.27 ng/mL). Plasma MMP-28 levels in patients with mild (n=24), moderate (n=31), or severe (n=24) aortic valve stenosis were 0.74 (0.25-2.23), 1.46 (0.50-3.22), and 4.13 (1.54-6.18) ng/mL, respectively, indicating that the patients with severe aortic valve stenosis had significantly higher MMP-28 levels than the patients with moderate or mild aortic valve stenosis (both P<0.01). Regression analysis using the general linear model further revealed that plasma MMP-28 level was correlated with the peak blood flow velocity and mean pressure gradient of the transaortic valve, and the correlations were statistically significant (both P<0.01). CONCLUSIONS MMP-28 level is significantly elevated in severe cases of calcific aortic valve stenosis. Moreover, plasma MMP-28 levels are positively correlated with the mean pressure gradients and peak blood flow velocity of the transaortic valve.

Pregnancy and cardiac interventions: What are the optimal management options?

Cardiac disease is the leading cause of maternal mortality in the United Kingdom. Major causes of cardiac death in pregnant women include cardiomyopathies, myocardial infarction, ischemic heart disease, and aortic dissection. Uncorrected congenital heart disease and women who have had corrective or palliative surgery may have complicated pregnancies as well. Some women with significant cardiac disease are unable to meet the increased physiological demands of pregnancy. Of these, those who do not respond to medical treatment may require surgical correction such as coronary artery bypass grafting. The risk of cardiac operations for pregnant women is similar to that for nonpregnant women but the fetal mortality rate remains high. Contributing factors to high fetal mortality rates include timing, urgency of operation, and the fetal/fetoplacental response to cardiopulmonary bypass. The aim of this review is to summarize current evidence in utilizing the different management approaches of cardiac issues during pregnancy.