Feasibility and Exploratory Efficacy Evaluation of the Embrella Embolic Deflector System for the Prevention of Cerebral Emboli in Patients Undergoing Transcatheter Aortic Valve Replacement

Neuroprotection Devices in Cardiac Catheterization Laboratories: Does It Sufficiently Protect Our Patients?

Stroke is a devastating complication of cardiovascular interventions. Intraprocedural stroke is a well-documented and feared risk of cardiac percutaneous transcatheter procedures. If clinically significant strokes are absent, silent strokes remain the next in line to pose large concerns related to future cognitive decline, stroke risk, and overall increased morbidity and mortality. Cerebral protection devices (CPD) developed overtime aim to neutralize this risk through either a capture-based filter or a deflector mechanism. Many CPDs exist currently, each one unique, with varying degrees of evidence. The adoption of CPDs has allowed cardiac percutaneous transcatheter procedures to be carried out in patients with high thromboembolic risks who may have historically been discommended. Though skewed towards certain devices and transcatheter procedures, a large body of evidence is still present across other devices and procedures. This review will discuss clinical importance and respective stroke rates, updated evidence surrounding CPDs, differing opinions across types of CPDs, cost benefits, and what lies ahead for CPDs within the realm of procedures undertaken in cardiac catheterization laboratories.

Optimizing Outcomes in Transcatheter Aortic Valve Replacement Addressing Cerebrovascular Complications and Enhancing Patient Safety

Transcatheter aortic valve replacement (TAVR) has revolutionized the treatment of severe aortic stenosis, becoming the gold standard for many patients. Despite its advantages over surgical aortic valve replacement, TAVR is associated with significant complications, including paravalvular leakage, conduction disorders, and cerebrovascular events. This review focuses on the pathophysiology, incidence, and management of cerebrovascular complications following TAVR. We explore the mechanisms leading to these events, including embolization of debris from the calcified valve and aortic arch, and the role of procedural factors. The review also discusses the timing of cerebrovascular events, diagnostic approaches, and potential preventive strategies, including embolic protection devices. Understanding these complications is crucial for improving patient outcomes and refining TAVR techniques.

Cerebrovascular Events in Patients Undergoing Transcatheter Aortic Valve Replacement: A Review

Cerebrovascular events (CVEs) are a dreaded complication of transcatheter aortic valve replacement (TAVR). They are associated with significant mortality, morbidity, and reduced quality of life and impose a significant burden to health care systems. Although the rates of clinical stroke have reduced since the advent of TAVR, it remains an important complication, particularly as TAVR is increasingly utilized. CVE may occur at the time of the TAVR, as a direct consequence of the procedure, or may occur later, related to thrombosis of the prosthetic valve, atrial fibrillation, and other comorbidities. Imaging of the brain has revealed a high prevalence of subclinical cerebral infarcts (68%-98%) associated with the TAVR procedure. Although their clinical significance has not been fully established, clinically evident CVE ranges between 3% and 5% in patients considered at high operative risk to between 1% and 3% in low operative risk patients. Periprocedural CVEs are largely the result of embolization of the thrombus and tissue derived from the valve, vasculature, or myocardium. Cerebral embolic protection devices have been studied in multiple trials, with some evidence supporting a reduction in new cerebral lesion volume, number, and potentially disabling strokes. However, thus far, there is no robust evidence that they reduce the overall stroke rate. The number and severity of comorbidities, in particular, new-onset atrial fibrillation, are associated with CVEs. Valve thrombosis diagnosed using computed tomography as areas of hypoattenuated leaflet thickening has been identified in 10% to 15% of patients. This is a dynamic process associated with an increase in CVEs, but that resolves with anticoagulation or sometimes without it. Routine use of anticoagulation compared with a single antiplatelet agent is associated with an increased risk of bleeding, without any additional alleviation in risk of thromboembolism. Future studies to improve risk stratification could facilitate the tailoring of preventive therapies to patients at high risk of CVE, who stand to gain the most benefit.

Cerebral Embolic Protection Devices: Are There Any Indications in Transcatheter Aortic Valve Replacement?

Stroke following transcatheter aortic valve replacement (TAVR) is a significant and life-threatening adverse event. The vast majority of these incidents occur during the TAVR procedure or within the first 24 h following TAVR, with a notable prevalence of cerebral embolic events. In response to this concern, cerebral embolic protection devices (CEPDs) have been designed to mitigate the risk of peri-procedural ischemic stroke during TAVR. The primary objective of CEPDs is to diminish the intraprocedural burden associated with new silent ischemic brain injuries. Despite the development of several CEPDs, their clinical efficacy remains uncertain. In this review, we delve into a comprehensive analysis of the utilization of CEPDs in patients undergoing TAVR, exploring insights from the existing literature. Additionally, we aim to present future perspectives and discuss the clinical implications associated with the incorporation of CEPDs in TAVR procedures.

Cerebral embolic protection for stroke prevention during transcatheter aortic valve replacement

INTRODUCTION

Cerebral Embolic Protection Device (CEPD) captures emboli during Transcatheter Aortic Valve Replacement (TAVR). With recently published pivotal trials and multiple cohort studies reporting new data, there is a need to re-calibrate available statistical evidence.

METHODS

A systematic literature search was conducted across databases from inception till February 2023. Dichotomous outcomes were pooled using Odds Ratio (OR), while continuous outcomes were pooled using Standardized Mean Difference (SMD) along with 95% corresponding intervals (95% CIs).

RESULTS

Data was included from 17 studies (7 RCTs, 10 cohorts, n = 155,829). Use of CEPD was associated with significantly reduced odds of stroke (OR = 0.60, 95% CI = 0.43-0.85, p = 0.003). There was no significant difference in disabling stroke (p = 0.25), non-disabling stroke (p = 0.72), and 30-day mortality (p = 0.10) between the two groups. There were no significant differences between the two groups for Diffusion-Weighted Magnetic Resonance Imaging (DW-MRI) findings, acute kidney injury, risk of pacemaker implantation life-threatening bleed, major bleed, minor bleed, worsening National Institute of Health Stroke Scale (NIHSS), modified Rankin Scale (mRS) and vascular complications (p > 0.05).

CONCLUSIONS

The use of CEPD during TAVR reduced the incidence of all-stroke (p = 0.003); however, there were no significant differences in any of the other pooled outcomes (p > 0.05).

REGISTRATION

The protocol of this meta-analysis was registered with the Open Science framework [https://doi.org/10.17605/OSF.IO/7W564] before data acquisition was started.

Clinical impact of cerebral protection during transcatheter aortic valve implantation

BACKGROUND

Embolization of debris can complicate transcatheter aortic valve implantation (TAVI) causing stroke. Cerebral embolism protection (CEP) devices can divert or trap debris.

PURPOSE

To evaluate the efficacy of CEP during TAVI vs the standard procedure.

DATA SOURCES

PubMed, SCOPUS and DOAJ 1/01/2014-04/12/2023.

STUDY SELECTION

Randomized and observational studies comparing CEP versus standard TAVI, according to PRISMA.

PRIMARY OUTCOME

stroke.

SECONDARY OUTCOMES

death, bleeding, vascular access complications, acute kidney injury and infarct area.

DATA EXTRACTION

Two investigators independently assessed study quality and extracted data.

DATA SYNTHESIS

Twenty-six articles were included (540.247 patients). The primary endpoint was significantly lower (RR = 0.800 95%CI:0.682-0.940; p = 0.007) with CEP. Similarly, death rates were significantly lower with CEP (RR = 0.610 95%CI:0.482-0.771; p < 0.001). No difference was found for bleeding (RR = 1.053 95%CI:0.793-1.398; p = 0.721), vascular complications (RR = 0.937 95%CI:0.820-1.070; p = 0.334) or AKI (RR = 0.982 95%CI:0.754-1.279; p = 0.891).

CONCLUSIONS

Use of CEP during TAVI is associated with improved outcomes. Future studies will identify patients who benefit most from CEP.

Cerebral Embolic Protection Devices for Transcatheter Aortic Valve Replacement: Review of the Literature and Future Perspectives

PURPOSE OF REVIEW

Transcatheter aortic valve replacement (TAVR) has been a revolutionary therapy in the treatment of aortic valve stenosis. The risk of stroke associated with TAVR has decreased significantly since its introduction; however, it remains a devastating complication when it does occur.

RECENT FINDINGS

Many of the strokes associated with TAVR occur peri-procedurally and are thought to be due to embolic debris entering the cerebrovascular circulation. A number of different cerebral embolic protection devices (CEPD) have been developed and are in various stages of testing and use. The results from clinical trials evaluating the role for CEPD to reduce the risk of stroke have been mixed. As a result, their uptake has been very heterogeneous. This review provides a summary of the diverse CEPD devices available for use and outlines the clinical evidence available to date.

Chronological vs Biological Age in Interventional Cardiology: A Comprehensive Approach to Care for Older Adults: JACC Family Series

Aging is the gradual decline in physical and physiological functioning leading to increased susceptibility to stressors and chronic illnesses, including cardiovascular disease. With an aging global population, in which 1 in 6 individuals will be older than 60 years by 2030, interventional cardiologists are increasingly involved in providing complex care for older individuals. Although procedural aspects remain their main clinical focus, interventionalists frequently encounter age-associated risks that influence eligibility for invasive care, decision making during the intervention, procedural adverse events, and long-term management decisions. The unprecedented growth in transcatheter interventions, especially for structural heart diseases at extremes of age, have pushed age-related risks and implications for cardiovascular care to the forefront. In this JACC state-of-the-art review, the authors provide a comprehensive overview of the aging process as it relates to cardiovascular interventions, with special emphasis on the difference between chronological and biological aging. The authors also address key considerations to improve health outcomes for older patients during and after their invasive cardiovascular care. The role of "gerotherapeutics" in interventional cardiology, technological innovation in measuring biological aging, and the integration of patient-centered outcomes in the older adult population are also discussed.

Stroke after Cardiac Surgery: A Risk Factor Analysis of 580,117 Patients from UK National Adult Cardiac Surgical Audit Cohort

Cerebrovascular accident is the most ominous complication observed after cardiac surgery, carrying an increased risk of morbidity and mortality. Analysis of the problem shows its multidimensional nature. In this study, we aimed to identify major determinants among classic variables, either demographic, clinical or type of surgical procedure, based on the analysis of a large dataset of 580,117 patients from the UK National Adult Cardiac Surgical Audit (NACSA). For this purpose, univariate and multivariate logistic regression models were utilized to determine associations between predictors and dependent variable (Stroke after cardiac surgery). Odds ratios (ORs) and 95% confidence intervals (CIs) were constructed for each independent variable. Statistical analysis allows us to confirm with greater certainty the predictive value of some variables such as age, gender, diabetes mellitus (diabetes treated with insulin OR = 1.37, 95%CI = 1.23-1.53), and systemic arterial hypertension (OR = 1.11, 95%CI = 1.05-1.16);, to emphasize the role of preoperative atrial fibrillation (OR = 1.10, 95%CI = 1.03-1.16) extracardiac arteriopathy (OR = 1.70, 95%CI = 1.58-1.82), and previous cerebral vascular accident (OR 1.71, 95%CI = 1.6-1.9), and to reappraise others like smoking status (crude OR = 1.00, 95%CI = 0.93-1.07 for current smokers) or BMI (OR = 0.98, 95%CI = 0.97-0.98). This could allow for better preoperative risk stratification. In addition, identifying those surgical procedures (for example thoracic aortic surgery associated with a crude OR of 3.72 and 95%CI = 3.53-3.93) burdened by a high risk of neurological complications may help broaden the field of preventive and protective techniques.

Direct transcatheter aortic valve implantation (TAVI) decreases silent cerebral infarction when compared to routine balloon valvuloplasty

PURPOSE

Silent cerebral infarctions (SCI), as determined by neuron-specific enolase (NSE) elevations, may develop after the transcatheter aortic valve implantation (TAVI) procedure. Our aim in this study was to compare the SCI rates between patients who underwent routine pre-dilatation balloon aortic valvuloplasty (pre-BAV) and patients who underwent direct TAVI without pre-BAV.

METHODS

A total of 139 consecutive patients who underwent TAVI in a single center using the self-expandable Evolut-R valve (Medtronic, Minneapolis, Minnesota, USA) were included in the study. The first 70 patients were included in the pre-BAV group, and the last 69 patients were included in the direct TAVI group. SCI was detected by serum NSE measurements performed at baseline and 12 h after the TAVI. New NSE elevations > 12 ng/mL after the procedure were counted as SCI. In addition, SCI was scanned by MRI (magnetic resonance imaging) in eligible patients.

RESULTS

TAVI procedure was successful in all of the study population. Post-dilatation rates were higher in the direct TAVI group. Post-TAVI NSE positivity (SCI) was higher in the routine pre-BAV group (55(78.6%) vs. 43(62.3%) patients, p = 0.036) and NSE levels were also higher in this group (26.8 ± 15.0 vs. 20.5 ± 14.8 ng/ml, p = 0.015). SCI with MRI was found to be significantly higher in the pre-BAV group than direct TAVI group (39(55.1%) vs. 31(44.9%) patients). The presence of atrial fibrillation and diabetes mellitus (DM), total cusp calcification volume, calcification at arcus aorta, routine pre-BAV and failure at first try of the prosthetic valve implantation were significantly higher in SCI (+) group. In the multivariate analysis, presence of DM, total cusp calcification volume, calcification at arcus aorta, routine pre-BAV and failure at first try of the prosthetic valve implantation were significantly associated with new SCI development.

CONCLUSIONS

Direct TAVI procedure without pre-dilation seems to be an effective method and avoidance of pre-dilation decreases the risk of SCI development in patients undergoing TAVI with a self-expandable valve.

Cerebral embolic protection during transcatheter heart interventions

Stroke remains a devastating complication of transcatheter aortic valve replacement (TAVR), with the incidence of clinically apparent stroke seemingly fixed at around 3% despite TAVR's significant evolution during the past decade. Embolic showers of debris (calcium, atheroma, valve material, foreign material) are captured in the majority of patients who have TAVR using a filter-based cerebral embolic protection device (CEPD). Additionally, in systematic brain imaging studies, the majority of patients receiving TAVR exhibit new cerebral lesions. Mechanistic studies have shown reductions in the volume of new cerebral lesions using CEPDs, yet the first randomised trial powered for periprocedural stroke within 72 hours of a transfemoral TAVR failed to meet its primary endpoint of showing superiority of the SENTINEL CEPD. The present review summarises the clinicopathological rationale for the development of CEPDs, the evidence behind these devices to date and the emerging recognition of cerebral embolisation in many non-TAVR transcatheter procedures. Given the uniqueness of each of the various CEPDs under development, specific trials tailored to their designs will need to be undertaken to broaden the CEPD field, in addition to evaluating the role of CEPD in non-TAVR transcatheter heart interventions. Importantly, the cost-effectiveness of these devices will require assessment to broaden the adoption of CEPDs globally.

Fighting Cardiac Thromboembolism during Transcatheter Procedures: An Update on the Use of Cerebral Protection Devices in Cath Labs and EP Labs

Intraprocedural stroke is a well-documented and feared potential risk of cardiovascular transcatheter procedures (TPs). Moreover, subclinical neurological events or covert central nervous system infarctions are concerns related to the development of dementia, future stroke, cognitive decline, and increased risk of mortality. Cerebral protection devices (CPDs) were developed to mitigate the risk of cardioembolic embolism during TPs. They are mechanical barriers designed to cover the ostium of the supra-aortic branches in the aortic arch, but newer devices are able to protect the descending aorta. CPDs have been mainly designed and tested to provide cerebral protection during transcatheter aortic valve replacement (TAVR), but their use in both Catheterization and Electrophysiology laboratories is rapidly increasing. CPDs have allowed us to perform procedures that were previously contraindicated due to high thromboembolic risk, such as in cases of intracardiac thrombosis identified at preprocedural assessment. However, several concerns related to their employment have to be defined. The selection of patients at high risk of thromboembolism is still a subjective choice of each center. The aim of this review is to update the evidence on the use of CPDs in either Cath labs or EP labs, providing an overview of their structural characteristics. Future perspectives focusing on their possible future employment are also discussed.

Aortic valve Replacement compared to Transcatheter Implant and its relationship with COgnitive Impairment (ARTICO) evaluated with neuropsychological and advanced neuroimaging: a longitudinal cohort study

BACKGROUND

Aortic stenosis is the most common valvulopathy in Western countries. The treatment of choice had been surgery aortic valve replacement (SAVR), but the improvement in endovascular approaches as transcatheter aortic valve implantation (TAVI), initially reserved for patients with very high surgical risk, has been extended to high and intermediate, and recently also to low-risk patients. Stroke and vascular cognitive impairment are the most important complications. It is not entirely clear which technique is best to avoid these complications as well as their impact. Our goal is to evaluate changes in cognitive performance in the early (1-month) and late (1-year) postoperative period in patients undergoing SAVR or TAVI, by extensive neuropsychological study (NRP) and advanced Magnetic Resonance Imaging (MRI). Specifically, to compare early and late cognitive changes after the intervention between both groups, the occurrence of stroke during follow-up and to compare the appearance of silent vascular lesions and changes in brain activity and functional connectivity with functional MRI during follow-up between both groups.

METHODS/DESIGN

Prospective longitudinal cohort study. A non-selected representative sample of 80 subjects, 40 SAVR and 40 TAVI to obtain a final sample of 36 eligible subjects in each group, ranging from 70 to 85 years old, with indication for aortic replacement and intermediate or high surgical risk will be studied. At baseline, within one month before the treatment, all individuals will undergo an extensive NRP and advanced MRI study. These studies will also be performed 1-month and 1-year after treatment, to assess the appearance of new vascular lesions, as well as changes in cognitive performance with respect to baseline.

DISCUSSION

This study aims to evaluate changes in cognitive performance as well as both clinical and silent vascular events occurring in the early (1-month) and late (1-year) periods after SAVR and TAVI. We will also analyze the correlation between neuropsychological and neuroimaging approaches in order to evaluate cognition. Therefore, it may provide high-quality data of cognitive changes and vascular events for both techniques, and be useful to tailor interventions to individual characteristics and ultimately aiding in decision-making.

TRIAL REGISTRATION

This study is register in Clinicaltrials.gov (NCT05235529) on 11th February 2022.

Safety and efficacy of cerebral embolic protection devices for patients undergoing transcatheter aortic valve replacement: An updated meta-analysis

Background and Aims

Cerebral embolic protection (CEP) devices are employed to capture embolic debris and reduce the risk of stroke during transcatheter aortic valve replacement (TAVR). Evidence is mixed regarding the safety and efficacy of CEP. We aimed to summarize the safety and effectiveness of CEP use during TAVR.

Methods

Electronic databases, including PubMed, PubMed Central, Scopus, Cochrane Library, and Embase, were searched using relevant search terms for articles relating to CEP. All relevant data from 20 studies were extracted into a standardized form. Statistical analyses were performed using Revman 5.4. Odds ratio (OR) or mean differences (MDs) were used to estimate the desired outcome with a 95% confidence interval (CI).

Results

Twenty studies (eight randomized controlled trials [RCTs]) involving 210,871 patients (19,261 in the CEP group and 191,610 in TAVR without the CEP group) were included. The use of CEP was associated with a lower odds of 30-day mortality by 39% (OR: 0.61, 95% CI: 0.53-0.70) and stroke by 31% (OR: 0.69, 95% CI: 0.52-0.92). Comparing devices, benefit in terms of mortality and stroke was observed with the use of the Sentinel device (Boston Scientific), but not among other devices. No differences were observed in the outcomes of acute kidney injury, major or life-threatening bleeding events, or major vascular complications between groups. When only RCTs were included, there were no observed differences in the primary or secondary outcomes for CEP versus no CEP use during TAVR.

Conclusions

The totality of evidence suggests a net benefit for the use of CEP, weighted by studies in which the Sentinal device was used. However, given the RCT subanalysis, additional evidence is needed to identify patients at the highest risk of stroke for optimal decision-making.

Cerebral Embolic Protection in Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR) is a treatment option for patients with symptomatic severe aortic stenosis across the entire spectrum of surgical risk. Recent trial data have led to the expansion of TAVR into lower-risk patients. With iterative technological advances and successive increases in procedural experience, the occurrence of complications following TAVR has declined. One of the most feared complications remains stroke, and patients consider stroke a worse outcome than death. There has therefore been great interest in strategies to mitigate the risk of stroke in patients undergoing TAVR. In this paper, we will discuss mechanisms and predictors of stroke after TAVR and describe the currently available cerebral embolic protection devices, including their design and relevant clinical studies pertaining to their use. We will also review the current overall evidence base for cerebral embolic protection during TAVR and ongoing randomized controlled trials. Finally, we will discuss our pragmatic recommendations for the use of cerebral embolic protection devices in patients undergoing TAVR.

Cerebral Embolic Protection Devices: Current State of the Art

Transcatheter aortic valve replacement (TAVR) has become a first-line treatment for severe aortic stenosis with intermediate to high-risk population with its use increasingly expanding into younger and low-risk cohorts as well. Cerebrovascular events are one of the most serious consequential complications of TAVR, which increase morbidity and mortality. The most probable origin of such neurological events is embolic in nature and the majority occur in the acute phase after TAVR when embolic events are most frequent. Cerebral embolic protection devices have been designed to capture or deflect these emboli, reducing the risk of peri-procedural ischaemic events. They also carry the potential to diminish the burden of new silent ischemic lesions during TAVR. Our review explores different types of these device systems, their rationale, and the established clinical data.

Utility of Cerebral Embolic Protection Devices in Transcatheter Procedures: A Systematic Review and Meta-Analysis

BACKGROUND

With the emergence of the largest randomized control trial to date - the Stroke Protection With Sentinel During Transcatheter Aortic Valve Replacement (PROTECTED TAVR) study- we sought to conduct an updated meta-analyses to evaluate the utility of CEP devices on both clinical outcomes and neuroimaging parameters.

METHODS

Electronic databases were queried through November 2022 for clinical trials comparing the utility of Cerebral Embolic Protection (CEP) devices in Transcatheter Aortic Valve Replacement (TAVR) with non-CEP TAVR procedures. Meta-analyses were performed using the generic inverse variance technique, and a random-effects model, and results are presented as weighted mean differences (WMD) for continuous outcomes, and hazard ratios (HR) for dichotomous outcomes. Outcomes of interest included stroke, disabling stroke, non-disabling stroke, bleeding, mortality, vascular complications, new ischemic lesions, acute kidney injury (AKI) and total lesion volume.

RESULTS

13 studies (8 RCTs, 5 observational studies) consisting of 128,471 patients were included in the analysis. Results from our meta-analyses showed a significant reduction in stroke (OR: 0.84 [0.74 - 0.95]; P < 0.01; I² = 0%), disabling stroke (OR: 0.37 [0.21 - 0.67]; P < 0.01; I² = 0%) and bleeding events (OR: 0.91 [0.83 - 0.99]; P = 0.04; I² = 0%) through CEP device use in TAVR. The use of CEP devices had no significant impact on non-disabling stroke (OR: 0.94 [0.65 - 1.37]; P < 0.01; I² = 0%), mortality (OR: 0.78 [0.53 - 1.14]; P < 0.01; I² = 17%), vascular complications (OR: 0.99 [0.63 - 1.57]; P < 0.01; I² = 28%), AKI (OR: 0.78 [0.46 - 1.32]; P < 0.01; I² = 0%), new ischemic lesions (MD: -1.72 [-4.01, 0.57]; p < 0.001; I² = 95%) and total lesion volume (MD: -46.11 [-97.38, 5.16]; p < 0.001; I² = 81%).

CONCLUSIONS

The results suggest that CEP device use was associated with a lower risk of disabling stroke and bleeding events in patients undergoing TAVR.

Serial neurocognitive changes following transcatheter aortic valve replacement: comparison between low and intermediate-high risk groups

Background: Data comparing the neurocognitive trajectory between low and intermediate-high risk patients following transcatheter aortic valve replacement (TAVR) is never reported.

Aims: To report serial neurocognitive changes up to 1 year post-TAVR in low and intermediate-high risk groups as well as overall cohort.

Methods: Prospective neurological assessments (NIHSS and Barthel Index), global cognitive tests (MMSE and Alzheimer Disease Assessment Scale–Cognitive Subtest, ADAS-cog) and executive performances (Color Trail Test A and B and verbal fluency), were applied at baseline, 3 months and 1 year post-TAVR.

Results: In overall cohort, persistent improvement to 1 year in MMSE, ADAS-cog, Color Trail Test A and B was found. According to the STS score, the study cohort was divided into low (<4%, N = 81) and intermediate-high (≧4%, N = 75) risk groups. The baseline neurologic and cognitive performance was significantly worse in intermediate-high risk group. Slight improvement on general neurological functions (Barthel index and proportion of NIHSS>0 patients) at 1 year could be observed only in intermediate-high risk group. In global cognitive assessments, improvement in MMSE and ADAS-cog at 1 year was found in both groups, but the proportion of cognitive improvement was more obvious in intermediate-high risk group. In Color Trail Tests and verbal fluency, significant and persistent improvement up to 1 year could be observed only in low risk group.

Conclusions: TAVR was associated with persistent improvement in global cognitive function, as well as in attention and psychomotor processing speed, up to 1 year in overall cohort. However, improvement in tests for executive functions can only be seen in low risk group.

Case Report: Osmotic Demyelination Syndrome After Transcatheter Aortic Valve Replacement: Case Report and Review of Current Literature

Background

Osmotic demyelination syndrome (ODS) has a low incidence but is a life-threatening neurological disorder whose common cause is rapid overcorrection of chronic hyponatremia. Transcatheter aortic valve replacement (TAVR) is a new and important therapy for patients with aortic valve stenosis. In this article, we discuss the case of a 64-year-old woman who developed ODS after TAVR and provide a literature review.

Case Presentation

A 64-year-old female patient was admitted to the hospital with chest tightness, shortness of breath, and fatigue for 2 months, with worsening of symptoms for 3 days prior to presentation. Auscultation revealed crackles in the lung fields, and systolic murmurs could be easily heard in the aortic area. Echocardiography showed severe aortic stenosis. Chest X-ray showed pulmonary oedema. Laboratory examinations showed that her serum sodium was 135 mmol/L. The patient received a diuretic to relieve her symptoms but showed little benefit. Her symptoms worsened, and her blood pressure dropped. Then, she underwent emergency TAVR under extracorporeal membrane oxygenation (ECMO) support. After the operation, her urine output increased markedly, and serum sodium increased sharply from 140 to 172 mmol/L. An MRI scan showed multiple lesions in the pons suggestive of ODS.

Conclusion

To date, this is the first reported case of a patient who developed ODS after receiving TAVR. In current clinical practice, diuretics are often used in aortic stenosis patients because of pulmonary oedema. After a patient receives TAVR, kidney perfusion pressure quickly returns to normal, and with the residual effect of a high-dose diuretic, balances of fluid volume and electrolyte levels in this phase are quite fragile and must be carefully managed. If a patient has neurological symptoms/signs during this phase, ODS should be considered, and MRI might be necessary.

Cerebral embolic protection devices during transcatheter aortic valve implantation, the current state of the art

Stroke after transcatheter aortic valve (TAVI) is a devastating adverse event. The majority of these occur in the acute phase following TAVI where cerebral embolic events are frequent. Cerebral embolic protection devices (CEPD) have been developed to minimise the risk of peri-procedural ischaemic stroke during TAVI. CEPD have the potential to lower intraprocedural burden of new silent ischaemic brain injury. Several CEPD have been developed, but their clinical benefit remains unknown. Herein, we aimed to review the impact of the use of CEPD, in patients undergoing TAVI, on the reduction of strokes or the onset of new ischaemic lesions.

Neurologic Dysfunction and Neuroprotection in Transcatheter Aortic Valve Implantation

Transcatheter aortic valve implantation (TAVI) is a fast-growing procedure. Expanding to low-risk patients, it has surpassed surgical aortic valve implantation in frequency and has been associated with excellent outcomes. Stroke is a devastating complication after transcatheter aortic valve implantation. Silent brain infarcts identified by diffusion-weighted magnetic resonance imaging are present in most patients following TAVI. Postoperative delirium and cognitive dysfunction are common neurologic complications. The stroke and silent brain infarcts are likely caused by particulate emboli released during the procedure. Intravascularly positioned cerebral embolic protection devices are designed to prevent debris from entering the aortic arch vessels to avoid stroke. Despite promising design, randomized clinical trials have not demonstrated a reduction in stroke in patients receiving cerebral embolic protection devices. Similarly, the association of cerebral embolic protection devices with silent brain infarcts, postoperative delirium, and cognitive dysfunction is uncertain. Monitored anesthesia care or conscious sedation is as safe as general anesthesia and is associated with lower cost, but different anesthetic techniques have not been shown to decrease stroke risk, postoperative delirium, or cognitive dysfunction. Anesthesiologists play important roles in providing perioperative care including management of neurologic events in patients undergoing TAVI. Large randomized clinical trials are needed that focus on the correlation between perioperative interventions and neurologic outcomes.

"Tailor-made" Total Cerebral Protection during Transcatheter Aortic Valve Implantation

Transcatheter aortic valve implantation (TAVI) is an alternative treatment to surgical aortic valve replacement for treating severe aortic stenosis. With the increased use of TAVI, the risk of cerebrovascular complications during the procedure has become an emerging problem. We evaluated the safety and feasibility of our total cerebral protection methods using embolic protection devices (EPDs) for carotid artery stenting. We collected the results of cases in which the clinical team determined that our protection method was necessary among patients undergoing TAVI from May to October 2019 in our medical center. We applied this method to patients who had a potentially high risk of cerebrovascular events during the procedure. The methods of protection were selected comprehensively based on the potential of collateralization of brain perfusion when some arteries were blocked with a balloon, accessibility of the brain arteries, and the ability to cover the brain arteries with devices. Five patients, aged 83.8 ± 1.8 years, were included in the study. Technical success was achieved in all five patients. No cases showed any new neurological symptoms after the procedures; however, head MRI on the day after showed new ischemic lesions in three of five cases (60%). In all cases, emboli were found in the collected filters. This report demonstrates protection of the entire perfusion area in each case using EPDs in patients at high risk of intraoperative embolism. The methods we used were feasible and can potentially reduce cerebrovascular events following TAVI.

The Use and Outcomes of Cerebral Protection Devices for Patients Undergoing Transfemoral Transcatheter Aortic Valve Replacement in Clinical Practice

OBJECTIVES

This study hypothesized that cerebral protection prevents strokes in patients undergoing transfemoral transcatheter aortic valve replacement (TAVR) in clinical practice.

BACKGROUND

Preventing strokes is an important aim in TAVR procedures. Embolic protection devices may protect against cardiac embolism during TAVR, but their use and outcomes in clinical practice remain controversial.

METHODS

Isolated transfemoral TAVR procedures performed in Germany with or without cerebral protection devices were extracted from a comprehensive nationwide billing dataset.

RESULTS

A total of 41,654 TAVR procedures performed between 2015 and 2017 were analyzed. The overall share of procedures incorporating cerebral protection devices was 3.8%. Patients receiving cerebral protection devices were at increased operative risk (European System for Cardiac Operative Risk Evaluation score 13.8 vs. 14.7; p < 0.001) but of lower age (81.1 vs. 80.6 years; p = 0.001). To compare outcomes that may be related to the use of cerebral protection devices, a propensity score comparison was performed. The use of a cerebral protection device did not reduce the risk for stroke (adjusted risk difference [aRD]: +0.88%; 95% confidence interval [CI]: -0.07% to 1.83%; p = 0.069) or the risk for developing delirium (aRD: +1.31%; 95% CI: -0.28% to 2.89%; p = 0.106) as a sign of acute brain failure. Although brain damage could not be prevented, in-hospital mortality was lower in the group receiving a cerebral protection device (aRD: -0.76%; 95% CI: -1.46% to -0.06%; p = 0.034).

CONCLUSIONS

In this large national database, cerebral embolic protection devices were infrequently used during TAVR procedures. Device use was associated with lower mortality but not a reduction in stroke or delirium. Future studies are needed to confirm these findings.

Efficacy and safety of cerebral embolic protection systems during transcatheter aortic valve replacement: a review of current clinical findings

INTRODUCTION

Cerebrovascular events are one of the most serious consequences after transcatheter aortic valve replacement (TAVR). More than half of the cerebrovascular events following TAVR are due to procedure-related emboli. Embolic protection devices (EPDs) have the potential to decrease cerebrovascular events during TAVR procedure. However, randomized controlled trials (RCTs) have not conclusively determined if EPDs are effective, likely because of small number of patients enrolled. However, meta-analyses and propensity-matched analyses from large registries have shown efficacy and suggest the importance of EPDs in prevention of stroke during TAVR and perhaps other structural heart procedures.

AREAS COVERED

This review will focus on clinical and histopathologic studies examining the efficacy, safety, and histopathologic device capture findings in the presence and absence of EPDs during TAVR procedures.

EXPERT OPINION

Clinical studies have not conclusively determined the efficacy of EPDs. Current ongoing large-scale RCT (PROTECTED TAVR [NCT04149535]) has the potential to prove their efficacy. Histopathological evaluation of debris captured by EPDs contributes to our understanding of the mechanisms of TAVR procedure-related embolic events and suggests the importance of preventing cerebral embolization of debris released during this and other structural heart procedures.

Advancements in Transcatheter Aortic Valve Implantation: A Focused Update

Transcatheter aortic valve implantation (TAVI) has become the leading technique for aortic valve replacement in symptomatic patients with severe aortic stenosis with conventional surgical aortic valve replacement (SAVR) now limited to patients younger than 65-75 years due to a combination of unsuitable anatomies (calcified raphae in bicuspid valves, coexistent aneurysm of the ascending aorta) and concerns on the absence of long-term data on TAVI durability. This incredible rise is linked to technological evolutions combined with increased operator experience, which led to procedural refinements and, accordingly, to better outcomes. The article describes the main and newest technical improvements, allowing an extension of the indications (valve-in-valve procedures, intravascular lithotripsy for severely calcified iliac vessels), and a reduction of complications (stroke, pacemaker implantation, aortic regurgitation).

Généreux P, Piazza N, Alu MC, Nazif T, Hahn RT, Pibarot P, Bax JJ, Leipsic JA, Blanke P, Blackstone EH, Finn MT, Kapadia S, Linke A, Mack MJ, Makkar R, Mehran R, Popma JJ, Reardon M, Rodes-Cabau J, Van Mieghem NM, Webb JG, Cohen DJ, Leon MB. Valve Academic Research Consortium 3: updated endpoint definitions for aortic valve clinical research

Aims 

The Valve Academic Research Consortium (VARC), founded in 2010, was intended to (i) identify appropriate clinical endpoints and (ii) standardize definitions of these endpoints for transcatheter and surgical aortic valve clinical trials. Rapid evolution of the field, including the emergence of new complications, expanding clinical indications, and novel therapy strategies have mandated further refinement and expansion of these definitions to ensure clinical relevance. This document provides an update of the most appropriate clinical endpoint definitions to be used in the conduct of transcatheter and surgical aortic valve clinical research.

Methods and results 

Several years after the publication of the VARC-2 manuscript, an in-person meeting was held involving over 50 independent clinical experts representing several professional societies, academic research organizations, the US Food and Drug Administration (FDA), and industry representatives to (i) evaluate utilization of VARC endpoint definitions in clinical research, (ii) discuss the scope of this focused update, and (iii) review and revise specific clinical endpoint definitions. A writing committee of independent experts was convened and subsequently met to further address outstanding issues. There were ongoing discussions with FDA and many experts to develop a new classification schema for bioprosthetic valve dysfunction and failure. Overall, this multi-disciplinary process has resulted in important recommendations for data reporting, clinical research methods, and updated endpoint definitions. New definitions or modifications of existing definitions are being proposed for repeat hospitalizations, access site-related complications, bleeding events, conduction disturbances, cardiac structural complications, and bioprosthetic valve dysfunction and failure (including valve leaflet thickening and thrombosis). A more granular 5-class grading scheme for paravalvular regurgitation (PVR) is being proposed to help refine the assessment of PVR. Finally, more specific recommendations on quality-of-life assessments have been included, which have been targeted to specific clinical study designs.

Conclusions 

Acknowledging the dynamic and evolving nature of less-invasive aortic valve therapies, further refinements of clinical research processes are required. The adoption of these updated and newly proposed VARC-3 endpoints and definitions will ensure homogenous event reporting, accurate adjudication, and appropriate comparisons of clinical research studies involving devices and new therapeutic strategies.

Généreux P, Piazza N, Alu MC, Nazif T, Hahn RT, Pibarot P, Bax JJ, Leipsic JA, Blanke P, Blackstone EH, Finn MT, Kapadia S, Linke A, Mack MJ, Makkar R, Mehran R, Popma JJ, Reardon M, Rodes-Cabau J, Van Mieghem NM, Webb JG, Cohen DJ, Leon MB. Valve Academic Research Consortium 3: Updated Endpoint Definitions for Aortic Valve Clinical Research

AIMS

The Valve Academic Research Consortium (VARC), founded in 2010, was intended to (i) identify appropriate clinical endpoints and (ii) standardize definitions of these endpoints for transcatheter and surgical aortic valve clinical trials. Rapid evolution of the field, including the emergence of new complications, expanding clinical indications, and novel therapy strategies have mandated further refinement and expansion of these definitions to ensure clinical relevance. This document provides an update of the most appropriate clinical endpoint definitions to be used in the conduct of transcatheter and surgical aortic valve clinical research.

METHODS AND RESULTS

Several years after the publication of the VARC-2 manuscript, an in-person meeting was held involving over 50 independent clinical experts representing several professional societies, academic research organizations, the US Food and Drug Administration (FDA), and industry representatives to (i) evaluate utilization of VARC endpoint definitions in clinical research, (ii) discuss the scope of this focused update, and (iii) review and revise specific clinical endpoint definitions. A writing committee of independent experts was convened and subsequently met to further address outstanding issues. There were ongoing discussions with FDA and many experts to develop a new classification schema for bioprosthetic valve dysfunction and failure. Overall, this multi-disciplinary process has resulted in important recommendations for data reporting, clinical research methods, and updated endpoint definitions. New definitions or modifications of existing definitions are being proposed for repeat hospitalizations, access site-related complications, bleeding events, conduction disturbances, cardiac structural complications, and bioprosthetic valve dysfunction and failure (including valve leaflet thickening and thrombosis). A more granular 5-class grading scheme for paravalvular regurgitation (PVR) is being proposed to help refine the assessment of PVR. Finally, more specific recommendations on quality-of-life assessments have been included, which have been targeted to specific clinical study designs.

CONCLUSIONS

Acknowledging the dynamic and evolving nature of less-invasive aortic valve therapies, further refinements of clinical research processes are required. The adoption of these updated and newly proposed VARC-3 endpoints and definitions will ensure homogenous event reporting, accurate adjudication, and appropriate comparisons of clinical research studies involving devices and new therapeutic strategies.

First-in-Man Study Evaluating the Emblok Embolic Protection System During Transcatheter Aortic Valve Replacement

OBJECTIVES

This study sought to evaluate the feasibility of complete cerebral protection during transcatheter aortic valve replacement (TAVR) with a novel embolic protection device.

BACKGROUND

Evidences and data about new cerebral embolic protection devices are lacking and scarce.

METHODS

A prospective, nonrandomized, multicenter, first-in-man pilot study designed to evaluate the efficacy and safety of cerebral embolic protection utilizing the Emblok embolic protection system (Innovative Cardiovascular Solutions, Grand Rapids, Michigan) during TAVR. The Emblok is a transfemoral aortic filter that provide full coverage of the epiaortic vessels. Brain diffusion-weighted magnetic resonance imaging (DW-MRI) was performed at baseline and 2 to 5 days after TAVR. Primary endpoints were technical success and immediate cerebral embolic burden after TAVR, defined as number and volume of new brain lesions detected with DW-MRI at days 2 to 5 post-TAVR compared with baseline.

RESULTS

A total of 20 subjects were enrolled. The Emblok system was successfully positioned in all the cases. At 30-day follow-up, no major adverse cardiovascular and cerebrovascular events occurred. Nineteen (95%) patients had new ischemic defects at post-procedural DW-MRI. The median number of new lesions per patient was 10.00 (interquartile range [IQR]: 4.75 to 15.25). The total new lesion volume was 199.9 mm³ (IQR: 83.9 to 447.5 mm³) and the mean lesion volume per lesion was 42.5 mm³ (IQR: 21.5 to 75.6 mm³). Histopathologic analysis showed evidence of significant debris in 18 (90%) filters.

CONCLUSIONS

The Emblok embolic protection system appears to be feasible and safe during TAVR. The device was successfully placed and retrieved in all cases and no neurological events were observed. Cerebral total new lesion volume was similar to other trials on cerebral protection during TAVR, thus warranting a larger study. (European Study Evaluating the Emblok Embolic Protection System During TAVR; NCT03130491).

Brain Protection in the Endo-Management of Proximal Aortic Aneurysms

Neurological brain injury (NBI) remains the most feared complication following thoracic endovascular aortic repair (TEVAR), and can manifest as clinically overt stroke and/or more covert injury, detected only on explicit neuropsychological testing. Microembolic signals (MES) detected on transcranial Doppler (TCD) monitoring of the cerebral arteries during TEVAR and the high prevalence and incidence of new ischaemic infarcts on diffusion-weighted magnetic resonance imaging (DW-MRI) suggests procedure-related solid and gaseous cerebral microembolisation to be an important cause of NBI. Any intervention that can reduce the embolic burden during TEVAR may, therefore, help mitigate the risk of stroke and the covert impact of ischaemic infarcts to the function of the brain. This perspective article provides an understanding of the mechanism of stroke and reviews the available evidence regarding potential neuroprotective strategies that target high-risk procedural steps of TEVAR to reduce periprocedural cerebral embolisation.

Evolution, Predictors, and Neurocognitive Effects of Silent Cerebral Embolism During Transcatheter Aortic Valve Replacement

OBJECTIVES

The aim of this study was to assess the characteristics, predictors, evolution, and neurocognitive effects of silent cerebral ischemic lesions (SCILs).

BACKGROUND

Most patients undergoing transcatheter aortic valve replacement (TAVR) develop SCILs detectable on magnetic resonance imaging (MRI). The natural history and clinical relevance of SCILs are not well established.

METHODS

Cerebral MRI was performed within 7 days before TAVR to assess baseline status and age-related white matter change score. MRI was repeated post-operatively to assess the occurrence, location, number, and dimensions of SCILs. Patients developing SCILs underwent a third MRI examination at 3- to 5-month follow-up. A neurocognitive evaluation was performed before TAVR, at discharge, and at 3-month follow-up.

RESULTS

Of the 117 patients enrolled, 96 underwent post-procedural MRI; SCILs were observed in 76% of patients, distributed in all vascular territories, with a median number of 2 lesions, a median diameter of 4.5 mm, and a median total volume of 140 mm³. Independent predictors of SCIL occurrence were higher baseline age-related white matter change score and the use of self-expanding or mechanically expanded bioprostheses. Among 47 patients who underwent follow-up MRI, only 26.7% of post-procedural SCILs evolved into gliotic scar. SCIL occurrence was associated with a more pronounced transient neurocognitive decline early after TAVR and with lower recovery at follow-up.

CONCLUSIONS

SCILs occur in the vast majority of patients undergoing TAVR and are predicted by more diffuse white matter damage at baseline and by the use of non-balloon-expandable prostheses. Although most SCILs disappear within months, their occurrence has a limited but significant impact on neurocognitive function.

Recent Developments in Catheter-Based Cardiac Procedures

New developments in transcatheter valve technologies including aortic valve replacement and mitral valve and tricuspid valve interventions are described. Recent studies evaluating the success rate, patient outcomes, and anesthesiologic management of the procedures are discussed.

Cerebral protection devices for transcatheter aortic valve replacement

Aortic stenosis is the most prevalent primary valve disease in developed countries. Its prevalence is increasing due to population aging. Transcatheter aortic valve replacement (TAVR) is a sterling therapy for symptomatic patients with severe aortic stenosis and high or intermediate surgery risk. The number of procedures has increased exponentially expanding to younger and lower risk patients. Despite new-generation TAVR devices and enhanced operator skills, cerebrovascular events (CVEs) carry on being one of the most severe complications, increasing morbi-mortality. CVE might be under reported because there are few studies with rigorous neurological clinical assessment. Several imaging studies show most of CVE after TAVR has a probable embolic etiology. The risk of CVE ranges from 2.7% to 5.5% at 30 days. As TAVR expands to younger and lower risk patients, the prevention of stroke plays an increasingly important role. Cerebral protection devices (CPD) were designed to reduce the risk of CVE during TAVR. This review describes the scientific evidence on CVE after TAVR and summarizes the performance and results of the main CPDs.

Prevalence and Evolution of Susceptibility-Weighted Imaging Lesions in Patients With Artificial Heart Valves

Background

In patients with mechanical heart valves, cerebral susceptibility‐weighted imaging (SWI) lesions on magnetic resonance imaging, postulated to be caused by degenerative metallic abrasion, are frequently referred to as valve abrasion. It remains unclear whether valve implantation not requiring cardiopulmonary bypass or biological heart valves also shows those lesions.

Methods and Results

Two blinded readers rated SWI lesions and cerebral amyloid angiopathy probability according to established criteria on brain magnetic resonance imaging pre‐ and postinterventionally. We assessed the association between valve type/cardiopulmonary bypass use and SWI lesion count on the first postinterventional scan using multivariable logistic regression. On postinterventional magnetic resonance imaging, 57/58 (98%) patients with mechanical heart valves had at least 1 and 46/58 (79%) 3 or more SWI lesions, while 92/97 (95%) patients with biological heart valves had at least 1 and 72/97 (74%) 3 or more SWI lesions. On multivariate analysis, duration of cardiopulmonary bypass during implantation significantly increased the odds of having SWI lesions on the first postinterventional magnetic resonance imaging (β per 10 minutes 0.498; 95% CI, 0.116–0.880; P=0.011), whereas valve type showed no significant association (P=0.338). Thirty‐seven of 155 (23.9%) patients fulfilled the criteria of possible/probable cerebral amyloid angiopathy.

Conclusions

SWI lesions in patients with artificial heart valves evolve around the time point of valve implantation and the majority of patients had multiple lesions. The missing association with the valve type weakens the hypothesis of degenerative metallic abrasion and highlights cardiopulmonary bypass as the main risk factor for SWI occurrence. SWI lesions associated with cardiac procedures can mimic cerebral amyloid angiopathy. Further research needs to clarify whether those lesions are associated with intracranial hemorrhage after intravenous thrombolysis or anticoagulation.

Mid-Term Outcomes after Transapical and Transfemoral Transcatheter Aortic Valve Implantation for Aortic Stenosis and Porcelain Aorta with a Systematic Review of Transfemoral versus Transapical Approach

Background We have aimed to analyze early and mid-term outcomes of patients undergoing transapical/transfemoral transcatheter aortic valve implantation (TA-/TF-TAVI) for aortic stenosis and porcelain aorta (PAo) in our institution. Additionally, we postulated that the TA approach may be associated with a more favorable neurological outcome than the TF approach; hence, a systematic literature review was conducted.

Methods Between 2011 and 2017, 15 patients with PAo underwent TA-TAVI and 4 patients with PAo TF-TAVI at our institution. The assessment of PAo was done either intraoperatively after aborted sternotomy or via computed tomography for elective TAVI. We conducted mid-term follow-up. Furthermore, a systematic review was performed to compare the mortality and neurological outcomes of TF and TA-TAVI approaches.

Results TA/TF-TAVIs were performed with 100% device success, without paravalvular leakage ≥ 2 and without procedural death. The 30-day mortality/stroke rates were 6.6%/0% in TA-TAVI and 0%/25% in TF-TAVI, respectively. The 6-month, 1-year, and 2-year survival rates were in TA/TF-TAVI 93%/75%, 82%/66.6%, and 50%/0%, respectively.

The pooled results derived from the literature review were as follows: The prevalence of PAo in the TAVI population is 9.74%; the mean logistic EuroSCORE is 41.9% in TA-TAVI versus 16.2% in TF-TAVI; the mean 30-day mortality is 5.9% in TA-TAVI versus 6.3% in TF-TAVI, and the mean stroke is 0.8% in TA-TAVI versus 9% in TF-TAVI.

Conclusion TA-TAVI shows promising early and mid-term outcomes in patients with PAo. TF-TAVI performed in patients with PAo is likely to be associated with higher rates of stroke than TA-TAVI.

Pre-Dilatation Versus No Pre-Dilatation for Implantation of a Self-Expanding Valve in All Comers Undergoing TAVR: The DIRECT Trial

OBJECTIVES

The aim of this study was to compare the implantation of a self-expanding valve with or without balloon aortic valvuloplasty (BAV) in an open-label, noninferiority, randomized trial.

BACKGROUND

There are no randomized studies comparing the implantation of a self-expanding valve with (pre-BAV) or without BAV.

METHODS

Consecutive patients with severe aortic stenosis were randomly assigned to undergo transcatheter aortic valve replacement with the use of self-expanding prostheses with (pre-BAV) or without (no-BAV) pre-dilatation. The primary endpoint was device success according to the Valve Academic Research Consortium 2 criteria. Secondary endpoints included periprocedural mortality and stroke, new permanent pacemaker implantation, vascular complications, and 1-year mortality. The trial was scheduled to show noninferiority (Δ = 15%) of the direct versus the pre-BAV approach.

RESULTS

A total of 171 patients were randomized at 4 centers. Of these, 86 underwent transcatheter aortic valve replacement with pre-dilatation and 85 without. Device success was noninferior in the no-BAV group compared with the pre-BAV group (65 of 85 [76.5%] for no-BAV vs. 64 of 86 [74.4%] for pre-BAV; mean difference 2.1%; 90% confidence interval: -8.9% to 13%). In the no-BAV group, 25 patients (29.4%) underwent post-balloon dilatation, and in the pre-BAV group, 13 patients (15.1%) underwent post-balloon dilatation (p = 0.03). Regarding major vascular complications and permanent pacemaker implantation, there was no difference between the 2 groups (log-rank p = 0.49, log-rank p = 0.54). In 1-month completed follow-up for all patients, there was 1 periprocedural stroke (0.5%), without any deaths.

CONCLUSIONS

Direct, without balloon pre-dilatation, transcatheter aortic valve replacement with a self-expanding prosthesis system is noninferior to the pre-dilatation procedure. Lower post-dilatation rates were encountered in the group with pre-dilatation. (The Predilatation in Transcatheter Aortic Valve Implantation Trial [DIRECT]; NCT02448927).

Cerebral Embolic Protection in TAVI: Friend or Foe

Cerebrovascular accidents including stroke or transient ischaemic attack are one of the most feared complications after transcatheter aortic valve implantation. Transcatheter aortic valve implantation procedures have been consistently associated with silent ischaemic cerebral embolism as assessed by diffusion-weighted MRI. To reduce the risk of cerebrovascular accidents and silent emboli, cerebral embolic protection devices were developed with the aim of preventing procedural debris reaching the cerebral vasculature. The authors summarise the available data regarding cerebral embolic protection devices and its clinical significance.

Cerebral embolic protection devices during transcatheter aortic valve implantation: clinical versus silent embolism

Cerebrovascular events following transcatheter aortic valve implantation (TAVI) is one of the most devastating complications. Several studies with magnetic resonance or cerebral filters have demonstrated the universal brain embolization after TAVI, in the majority of patients clinically silent. Embolic protection devices (EPD) have been developed as a mechanical barrier to prevent these emboli to reach cerebral vasculature and potentially reduce neurological events. We review the current evidence about EPD in relation to histopathological and cerebral imaging findings and neurological events.

The Role of Cerebral Embolic Protection Devices During Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement is the therapy of choice for patients with severe aortic stenosis who have prohibitive or high surgical risk. However, the benefit of TAVR is attenuated by the occurrence of major disabling stroke which is associated with increased mortality and early-reduced quality of life. Despite advances in TAVR technology, stroke remains a serious complication that is associated with significant negative outcomes. The majority of these occur in the acute phase following TAVR where cerebral embolic events are frequent. Cerebral embolic protection devices (CEPD) have been developed to minimize the risk of peri-procedural ischemic stroke during TAVR. CEPD have the potential to reduce intraprocedural burden of new silent ischemic injury. In this review we outline the etiology and incidence of stroke in TAVR population, and systematically review current evidence for cerebral embolic protection devices.

Reversed Auxiliary Flow to Reduce Embolism Risk During TAVI: A Computational Simulation and Experimental Study

INTRODUCTION

Endovascular treatments, such as transcatheter aortic valve implantation (TAVI), carry a risk of embolization due to debris dislodgement during various procedural steps. Although embolic filters are already available and marketed, mechanisms underlying cerebral embolism still need to be elucidated in order to further reduce cerebrovascular events.

METHODS

We propose an experimental framework with an in silico duplicate allowing release of particles at the level of the aortic valve and their subsequent capture in the supra-aortic branches, simulating embolization under constant inflow and controlled hemodynamic conditions. The effect of a simple flow modulation, consisting of an auxiliary constant flow via the right subclavian artery (RSA), on the amount of particle entering the brachiocephalic trunk was investigated. Preliminary computational fluid dynamics (CFD) simulations were performed in order to assess the minimum retrograde flow-rate from RSA required to deviate particles.

RESULTS

Our results show that a constant reversed auxiliary flow of 0.5 L/min from the RSA under a constant inflow of 4 L/min from the ascending aorta is able to protect the brachiocephalic trunk from particle embolisms. Both computational and experimental results also demonstrate that the distribution of the bulk flow dictates the distribution of the particles along the aortic branches. This effect has also shown to be independent of release location and flow rate.

CONCLUSIONS

The present study confirms that the integration of in vitro experiments and in silico analyses allows designing and benchmarking novel solutions for cerebral embolic protection during TAVI such as the proposed embo-deviation technique based on an auxiliary retrograde flow from the right subclavian artery.