Heterogeneity of debris captured by cerebral embolic protection filters during TAVI

Examining the Role of Cerebral Embolic Protection Devices in Preventing Postoperative Stroke in Patients with a History of Stroke or Transient Ischemic: Insights from the National Inpatient Sample

Cerebral embolic protection devices (CEPD) during transcatheter aortic valve replacement (TAVR) have been shown to lower the risk of stroke during the procedure. However, their long-term and clinical effects on neuro-cognition are unknown. Therefore, we hypothesized the benefit of CEPD in TAVR patients with a prior history of stroke or transient ischemic attack (TIA). National Inpatient Sample (2019) and International Classification of Diseases, 10th Revision codes were used to identify patients undergoing TAVR with prior stroke or TIA. Propensity-matched analysis was performed to adjust for baseline characteristics and comorbidities. Primary outcome measures were postoperative stroke and all-cause mortality. Length of stay and hospital cost were secondary outcomes. Of 8450 unmatched TAVR patients with prior stroke or TIA in 2019, 1095 (13%) utilized CEPD. After propensity matching previous myocardial infarction (MI), coronary artery bypass grafting, and drug abuse were higher in the TAVR-only cohort. Postoperative stroke rate (1.4% vs 2.2%; P = 0.081) and odds [adjusted odds ratio (aOR), 0.48; 95% confidence interval (CI), 0.11-2.17; P = 0.341] were lower in the CEPD group. There was no difference in all-cause in-hospital mortality between the 2 groups (0.9% vs 1.0%). Length of stay (3 vs 2 days, P <0.001) and hospital expenditure ($172,711 vs $162,284; P = 0.002) were higher for the TAVR-only cohort. CEPD in TAVR patients with prior stroke or TIA did not show statistically significant postoperative stroke benefits. However, further larger-scale prospective studies are needed to evaluate the long-term neurocognitive benefits of CEPD in these patients. As the use of TAVR continues to expand, optimizing peri-procedural strategies such as the use of CEPD remains a critical area of research to improve patient outcomes.

Evaluation of cerebrovascular events via retinal angiography during transcatheter aortic valve implantation

OBJECTIVES

Patients receiving transcatheter aortic valve implantation (TAVI) are elderly with multiple comorbidities and at increased risk of perioperative cerebrovascular events. Retinal vasculature represents a surrogate of central nervous system circulation and is noninvasively achievable by retinal imaging. The aim of this study was to evaluate the applicability of retinal angiography of microvascular complications and association to cerebral ischemic events during TAVI.

DESIGN

One hundred patients (male 54%, age: median 82 years, range 64-95 years) undergoing TAVI were recruited for this study. Imaging of retinal vasculature was evaluated with a handheld fundus camera before, during and 1 month after. Cerebrovascular events were determined as a part of contemporary clinical evaluation with cerebral CT and CTA imaging when symptoms occurred.

RESULTS

Altogether 66/100 patients (66%) were included in the analysis. In-hospital ischemic event (transient ischemic attack, cerebral infarction) was observed in 1/66 patient (1.5%). Retinal vascular abnormalities occurred in 8/66 patients (12.1%); 4/66 patients (6.1%) were detected with a cholesterol plaque in the retinal artery, 2/66 (3%) a capillary leakage, 1/66 (1.5%) and optic disk hemorrhage and 1/66 (1.5%) a macular bleeding. No significant association between retinal vasculature abnormalities and cerebrovascular events was detected mainly due to the low event rate.

CONCLUSIONS

Perioperative evaluation of cerebrovascular ischemia with noninvasive imaging of retinal vasculature is possible in most patients undergoing TAVI. More data is needed to evaluate the association of cerebrovascular events and retinal microvascular abnormalities during the procedure.

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.

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.

Outcomes of Cerebral Embolic Protection for Bicuspid Aortic Valve Stenosis Undergoing Transcatheter Aortic Valve Replacement

Background There was limited high-quality evidence that illuminated the efficiency of cerebral embolic protection (CEP) use during transcatheter aortic valve replacement (TAVR) for bicuspid aortic valve (BAV) stenosis. Methods and Results In this retrospective cohort study, patients with BAV stenosis undergoing TAVR with or without CEP were identified by querying the National Inpatient Sample database. The primary end point was any stroke during the hospitalization. The composite safety end point included any in-hospital death and stroke. We applied propensity score-matched analysis to minimize standardized mean differences of baseline variables and compare in-hospital outcomes. From July 2017 to December 2020, 4610 weighted hospitalizations with BAV stenosis undergoing TAVR were identified, of which 795 were treated with CEP. There was a significant increase in the CEP use rate for BAV stenosis (P-trend <0.001). A total of 795 discharges with CEP use were propensity score matched to 1590 comparable discharges but without CEP. CEP use was associated with a lower incidence of in-hospital stroke (1.3% versus 3.8%; P<0.001), which in multivariable regression was also independently associated with the primary outcome (adjusted odds ratio=0.38 [95% CI, 0.18-0.71]; P=0.005) and the safety end point (adjusted odds ratio=0.41 [95% CI, 0.22-0.68] P=0.001). Meanwhile, no significant difference was found in the cost of hospitalization ($46 629 versus $45 147; P=0.18) or the risk of vascular complications (1.9% versus 2.5%; P=0.41). Conclusions This observational study supported CEP use for BAV stenosis, which was independently associated with less in-hospital stroke without burdening the patients with a high hospitalization cost.

Cerebral Ischemic Lesions after Transcatheter Aortic Valve Implantation in Patients with Non-Calcific Aortic Stenosis

Evidence for transcatheter aortic valve implantation (TAVI) is scarce among patients with non-calcific aortic stenosis, and it is not known whether aortic valve calcification is associated with new cerebral ischemic lesions (CILs) that are detected by diffusion-weighted magnetic resonance imaging. So, our study enrolled 328 patients who underwent transfemoral TAVI using a self-expanding valve between December 2016 and June 2021 from the TORCH registry (NCT02803294). A total of 34 patients were finally confirmed as non-calcific AS and the remaining 294 patients were included in the calcific AS group. Incidence of new CILs (70.6% vs. 85.7%, p = 0.022), number of lesions (2.0 vs. 3.0, p = 0.010), and lesions volume (105.0 mm3 vs. 200.0 mm3, p = 0.047) was significantly lower in the non-calcific AS group. However, the maximum and average lesion volumes were comparable between two groups. Non-calcific AS was associated with lower risk for developing new CILs by univariate logistic regression analysis [Odds ratio (OR): 0.040, 95% confident interval (CI): 0.18-0.90, p = 0.026] and multivariate analysis (OR: 0.031, 95% CI: 0.13-0.76, p = 0.010). In summary, non-calcific AS patients had a lower risk of developing new cerebral ischemic infarction after TAVI compared to calcific AS patients. However, new ischemic lesions were still found in over 70% of patients.

Cerebral embolic protection and severity of stroke following transcatheter aortic valve replacement

BACKGROUND

The cerebral embolic protection (CEP) device captures embolic debris during transcatheter aortic valve replacement (TAVR). However, the impact of CEP on stroke severity following TAVR remains unclear. Therefore, we aimed to examine whether CEP was associated with reduced severity of stroke following TAVR.

METHODS

This was a retrospective cohort study of 2839 consecutive patients (mean age: 79.2 ± 9.5 years, females: 41.5%) who underwent transfemoral TAVR at our institution between 2013 and 2020. We categorized patients into Sentinel CEP users and nonusers. Neuroimaging data were reviewed and the final diagnosis of a cerebrovascular event was adjudicated by a neurologist blinded to the CEP use or nonuse. We compared the incidence and severity (assessed by the National Institutes of Health Stroke Scale [NIHSS]) of stroke through 72 h post-TAVR or discharge between the two groups using stabilized inverse probability of treatment weighting (IPTW) of propensity scores.

RESULTS

Of the eligible patients, 1802 (63.5%) received CEP during TAVR and 1037 (36.5%) did not. After adjustment for patient characteristics by stabilized IPTW, the rate of overall stroke was numerically lower in CEP users than in CEP nonusers, but the difference did not reach statistical significance (0.49% vs. 1.18%, p = 0.064). However, CEP users had significantly lower rates of moderate-or-severe stroke (NIHSS ≥ 6: 0.11% vs. 0.69%, p = 0.013) and severe stroke (NIHSS ≥ 15: 0% vs. 0.29%, p = 0.046). Stroke following CEP use (n = 8), compared with stroke following CEP nonuse (n = 15), tended to carry a lower NIHSS (median [IQR], 4.0 [2.0-7.0] vs. 7.0 [4.5-19.0], p = 0.087). Four (26.7%) out of 15 patients with stroke following CEP nonuse died within 30 days, with no death after stroke following CEP use.

CONCLUSIONS

CEP use may be associated with attenuated severity of stroke despite no significant difference in overall stroke incidence compared with CEP nonuse. This finding is considered hypothesis-generating and needs to be confirmed in large prospective studies.

Antithrombotic therapy after transcatheter aortic valve implantation

INTRODUCTION

Transcatheter aortic valve implantation (TAVI) is a treatment option for patients with symptomatic severe aortic stenosis across the entire spectrum of surgical risk. TAVI conveys some risk for thrombotic complications, requiring antithrombotic drugs for their prevention. Bleeding events represent the major drawback of antithrombotic therapy, which should be carefully tailored over the individual patient's risk profile.

AREAS COVERED

This review aimed at exploring the rationale for the adoption of a tailored antithrombotic therapy after successful TAVI, with a description and analysis of common complications and their impact on therapy selection. In addition, we aimed at reviewing and discussing current knowledge in this area, with a main focus on the high-quality evidence supporting latest guideline recommendations. Finally, ongoing studies and future directions on antithrombotic therapy after TAVI were outlined.

EXPERT OPINION

Initial experience with antithrombotic therapy after TAVI was derived from percutaneous coronary intervention practice. Accruing evidence in the field led to the current monotherapy paradigm, which prioritizes oral anticoagulant and single antiplatelet therapy in patients with or without an established indication for long-term anticoagulation, respectively. Future studies will investigate the role of alternative antithrombotic strategies to improve clinical outcomes of TAVI patients by minimizing both thrombotic and bleeding complications.

Periprocedural Strategies for Stroke Prevention in Patients Undergoing Transcatheter Aortic Valve Implantation

Cerebrovascular events remain a serious complication in patients undergoing transcatheter aortic valve implantation with an incidence of 2–3% at 30 days. While expanding TAVI to younger low-risk patients, prevention of periprocedural strokes becomes even more important. Different cerebral embolic protection devices have been tested but a clear clinical benefit has not been demonstrated in randomized trials. Due to the multifactorial aetiology with different predisposing factors, stroke prevention should include procedural and periprocedural strategies. This article aims to summarize different approaches and discuss open questions.

Treatment of Bicuspid Aortic Valve Stenosis Using Transcatheter Heart Valves

The paucity of data regarding the use of transcatheter aortic valve replacement (TAVR) in bicuspid aortic valve (BAV) anatomy due to exclusion from pivotal studies and lack of studies assessing the long-term outcomes and valve performance continue to present a significant challenge as we expand TAVR to patients with BAV anatomy. This article discusses the important anatomic and clinical considerations in the selection and management of patients with BAV with TAVR and reviews the emerging evidence that increasingly suggests this procedure is safe, device success is excellent, and procedural outcomes are improving.

Neurocognitive Status after Aortic Valve Replacement: Differences between TAVI and Surgery

Over the past decade, indications for transcatheter aortic valve implantation (TAVI) have progressed rapidly—procedural numbers now exceed those of surgical aortic valve replacement (SAVR) in many countries, and TAVI is now a realistic and attractive alternative to SAVR in low-risk patients. Neurocognitive outcomes after TAVI and SAVR remain an issue and sit firmly under the spotlight as TAVI moves into low-risk cohorts. Cognitive decline and stroke carry a significant burden and predict future functional decline, reduced mobility, poor quality of life and increased mortality. Early TAVI trials used varying neurocognitive definitions, and outcomes differed significantly as a result. Recent international consensus statements defining endpoints following TAVI and SAVR have standardised neurological outcomes and facilitate interpretation and comparison between trials. The latest TAVI and SAVR trials have demonstrated more consistent and favourable neurocognitive outcomes for TAVI patients, and cerebral embolic protection devices offer the prospect of further refinement and improvement.