Thrombotic Versus Bleeding Risk After Transcatheter Aortic Valve Replacement

Upper extremity versus lower extremity for secondary access during transcatheter aortic valve implantation: rationale and design of the randomised TAVI XS trial

BACKGROUND

During transcatheter aortic valve implantation (TAVI), secondary access is required for angiographic guidance and temporary pacing. The most commonly used secondary access sites are the femoral artery (angiographic guidance) and the femoral vein (temporary pacing). An upper extremity approach using the radial artery and an upper arm vein instead of the lower extremity approach using the femoral artery and femoral vein may reduce clinically relevant secondary access site-related bleeding complications, but robust evidence is lacking.

TRIAL DESIGN

The TAVI XS trial is a multicentre, randomised, open-label clinical trial with blinded evaluation of endpoints. A total of 238 patients undergoing transfemoral TAVI will be included. The primary endpoint is the incidence of clinically relevant bleeding (i.e. Bleeding Academic Research Consortium (BARC) type 2, 3 or 5 bleeding) of the randomised secondary access site (either diagnostic or pacemaker access, or both) within 30 days after TAVI. Secondary endpoints include time to mobilisation after TAVI, duration of hospitalisation, any BARC type 2, 3 or 5 bleeding, and early safety at 30 days according to Valve Academic Research Consortium‑3 criteria.

CONCLUSION

The TAVI XS trial is the first randomised trial comparing an upper extremity approach to a lower extremity approach with regard to clinically relevant secondary access site-related bleeding complications. The results of this trial will provide important insights into the safety and efficacy of an upper extremity approach in patients undergoing transfemoral TAVI.

Antithrombotic Therapy in Patients Undergoing Transcatheter Aortic Valve Implantation

Transcatheter aortic valve implantation (TAVI) now represents the mainstay of treatment for severe aortic stenosis. Owing to its exceptional procedural efficacy and safety, TAVI has been extended to include patients at lower surgical risk, thus now encompassing a diverse patient population receiving this treatment. Yet, long-term outcomes also depend on optimal medical therapy for secondary vascular prevention, with antithrombotic therapy serving as the cornerstone. Leveraging data from multiple randomized controlled trials, the current guidelines generally recommend single antithrombotic therapy, with either single antiplatelet therapy (SAPT) or oral anticoagulation (OAC) alone in those patients without or with atrial fibrillation, respectively. Yet, individualization of this pattern, as well as specific case uses, may be needed based on individual patient characteristics and concurrent procedures. This review aims to discuss the evidence supporting antithrombotic treatments in patients treated with TAVI, indications for a standardized treatment, as well as specific considerations for an individualized approach to treatment.

What is the current optimal antithrombotic therapy after transcatheter aortic valve implantation? Current evidence from Japan and the world

Aortic stenosis (AS) is a major valvular disease that can have a negative impact on patients' prognosis, and its prevalence is increasing due to an aging population worldwide. Transcatheter aortic valve implantation (TAVI) is a well-established therapy for symptomatic severe AS utilized across the entire surgical risk spectrum. Based on the recently published evidence of large, randomized controlled trials (RCTs), the number of patients undergoing TAVI is increasing worldwide. Ischemic and bleeding events are common after TAVI and can have serious consequences both immediately after the procedure and in the long-term. Antiplatelet therapy has been traditionally recommended to prevent thromboembolic events after TAVI. The situation regarding the optimal antithrombotic regimen following TAVI is rapidly changing because many game-changing RCTs have been published. This report provides an overview of the current status and remaining issues in the field of optimal antithrombotic therapy following TAVI, including its possible effect on leaflet thrombosis.

Antithrombotic Treatment After Transcatheter Valve Interventions: Current Status and Future Directions

PURPOSE

The optimal antithrombotic strategy after transcatheter valve interventions is a subject of ongoing debate. Although there is evidence from randomized trials in patients undergoing transcatheter aortic valve replacement (TAVR), current evidence on optimal antithrombotic management after transcatheter mitral or tricuspid valve interventions is sparse. This article appraises the current evidence on this topic.

METHODS

This narrative review presents key research findings and guideline recommendations, as well as highlights areas for future research.

FINDINGS

After TAVR, randomized trial evidence suggests that single antiplatelet therapy is reasonable for patients without pre-existing indications for oral anticoagulation (OAC). If there is a concurrent indication for OAC, the addition of antiplatelet therapy increases bleeding risk. Whether direct oral anticoagulants achieve better outcomes than vitamin K antagonists is uncertain in this setting. Although OAC has been shown to reduce subclinical leaflet thrombosis (which may progress to structural valve degeneration), bleeding events are unacceptably high. There is a lack of randomized trial data comparing antithrombotic strategies after transcatheter mitral or tricuspid valve replacement or after mitral or tricuspid transcatheter edge-to-edge repair. Single antiplatelet therapy after mitral or tricuspid transcatheter edge-to-edge repair may be appropriate, whereas at least 3 months of OAC is suggested after transcatheter mitral valve replacement or transcatheter tricuspid valve replacement.

IMPLICATIONS

Randomized studies are warranted to address the knowledge gaps in antithrombotic therapy after transcatheter valve interventions and to optimize outcomes.

Using Upper Arm Vein as Temporary Pacemaker Access Site: A Next Step in Minimizing the Invasiveness of Transcatheter Aortic Valve Replacement

Background The femoral vein is commonly used as a pacemaker access site during transcatheter aortic valve replacement (TAVR). Using an upper arm vein as an alternative access site potentially causes fewer bleeding complications and shorter time to mobilization. We aimed to assess the safety and efficacy of an upper arm vein as a temporary pacemaker access site during TAVR. Methods We evaluated all patients undergoing TAVR in our center between January 2020 and January 2023. Upper arm, femoral, and jugular vein pacemaker access was used in 255 (45.8%), 191 (34.3%), and 111 (19.9%) patients, respectively. Clinical outcomes were analyzed according to pacemaker access in the overall population and in a propensity-matched population involving 165 upper arm and 165 femoral vein patients. Primary endpoint was Bleeding Academic Research Consortium (BARC) type 2, 3, or 5 pacemaker access site-related bleeding. Results In the overall population, primary endpoint was lowest for upper arm, followed by femoral and jugular vein access (2.4% vs. 5.8% vs. 10.8%, p = 0.003). Time to mobilization was significantly longer (p < 0.001) in the jugular cohort compared with the other cohorts. In the propensity-matched cohort, primary endpoint showed a trend toward lower occurrence in the upper arm compared with the femoral cohort (2.4% vs. 6.1%, p = 0.10). Time to mobilization was significantly shorter (480 vs. 1140 min, p < 0.001) in the upper arm cohort, with a comparable skin-to-skin time (83 vs. 85 min, p = 0.75). Cross-over from upper arm pacemaker access was required in 17 patients (6.3% of attempted cases via an upper arm vein). Conclusions Using an upper arm vein as a temporary pacemaker access site is safe and feasible. Its use might be associated with fewer bleeding complications and shorter time to mobilization compared with the femoral vein.

Bioprosthetic leaflet thrombosis and reduced leaflet motion after transcatheter aortic valve replacement: A systematic review and meta-analysis

BACKGROUND

Leaflet thrombosis and reduced leaflet motion have become a concern with the expanding use of transcatheter aortic valve replacement in lower-risk patients.

AIMS

To assess the proportions, predictors and clinical impact of leaflet thrombosis and reduced leaflet motion after transcatheter aortic valve replacement.

METHODS

We performed a meta-analysis of studies assessing the proportions of and/or clinical outcomes according to the presence of leaflet thrombosis after transcatheter aortic valve replacement identified with computed tomography and/or echocardiography.

RESULTS

Fifty-three studies, representing 25,258 patients undergoing transcatheter aortic valve replacement, were considered. The proportion of leaflet thrombosis was 5.2% overall, and was higher in computed tomography versus echocardiography (16.4% vs. 1.1%, respectively); reduced leaflet motion was identified in 11% of patients with four-dimensional computed tomography. Intra-annular bioprostheses were associated with a higher proportion of leaflet thrombosis, whereas chronic oral anticoagulation was protective for leaflet thrombosis in both computed tomography and echocardiographic studies (9.7% vs. 17.5%; relative risk [RR]: 0.51, 95% confidence interval [95% CI]: 0.37-0.71 and 0.9% vs. 2.7%; RR: 0.22, 95% CI: 0.06-0.79, respectively) and for reduced leaflet motion (2.5% vs. 12.4%; RR: 0.32, 95% CI: 0.13-0.76). Leaflet thrombosis was not associated with an increased risk of death, but with a higher risk of stroke in computed tomography studies (2.8% vs. 2.4%; RR: 1.63, 95% CI: 1.05-2.55), a difference more pronounced when considering reduced leaflet motion (3.5% vs. 1.7%; RR: 2.39, 95% CI: 0.63-8.34).

CONCLUSIONS

The proportion of leaflet thrombosis is highly variable according to the screening approach, the type of valve and the use of oral anticoagulation. The occurrence of cerebral events is increased when leaflet thrombosis and/or reduced leaflet motion are diagnosed, but leaflet thrombosis has no impact on survival.

Optimal antiplatelet and antithrombotic regimen post-transcatheter aortic valve replacement

BACKGROUND

There are limited data regarding optimal antiplatelet/antithrombotic therapy following transcatheter aortic valve replacement (TAVR).

METHODS

In this single-centre retrospective study including TAVR patients from 2012 to 2020, ischemic and bleeding outcomes were compared between antiplatelet (dual antiplatelet [DAPT] vs. single antiplatelet [SAPT]) and oral anticoagulation (OAC) groups using incidence rate, Kaplan-Meier and Cox proportional hazards analysis.

RESULTS

Total 492 patients (mean age 79.7 ± 7.7 years, 53.7% males, 83.5% Caucasian) were included. There was higher incidence of 1-year death or ischemia with DAPT vs. SAPT (23.6 vs. 14.8 per 100 patient-years [PY], incidence rate ratio [IRR] 1.60, 95% confidence interval [CI] 0.97-2.68, p = .05), especially in those without coronary artery disease (23.9 vs. 10.7 per 100 PY, IRR 2.24, 95% CI 1.10-4.47, p = .017). There was significantly higher major bleeding in those on OAC vs. no OAC (15 vs. 8 per 100 PY, IRR 1.87, 95% CI 1.10-3.11, p = .016), especially late (>1-year) bleeding (10.2 vs. 3.6 per 100 PY, IRR 2.81, 95% CI 1.33-5.92, p = .004). In multivariate analysis, DAPT was an independent predictor of death or ischemia (adjusted hazard ratio [aHR] 1.41, 95% CI 1.01-1.96, p = .041). OAC was an independent predictor of major bleeding (aHR 2.32, 95% CI 1.31-4.13, p = .004).

CONCLUSIONS

There is signal to harm with routine use of DAPT post-TAVR. There is higher incidence of late bleeding post-TAVR with OAC, suggesting potential role for alternate antithrombotic strategies.

Hemostatic Profiles of Patients Who Underwent Transcatheter Versus Surgical Aortic Valve Replacement Versus Percutaneous Coronary Intervention

Guidelines for transcatheter aortic valve replacement (TAVR) antithrombotic prophylaxis are extrapolated predominantly from percutaneous coronary intervention (PCI) data. Here, we examined temporal coagulation changes occurring in the early perioperative period to determine the pathobiologic validity of this supposition. This was a prospective observational study of consecutive patients who underwent transfemoral TAVR (n = 27), PCI (n = 12), or surgical aortic valve replacement (SAVR) requiring cardiopulmonary bypass and cross-clamping (n = 12). Blood samples were taken at 4 time points: T1 (baseline), after general anesthesia or sedation; T2, after heparin administration; T3, at the end of the procedure; and T4, 6 hours after the procedure. The samples were assessed concurrently using standard laboratory coagulation tests and viscoelastic tests of whole blood clotting, including the latest generation thromboelastometry (ROTEM sigma) and thromboelastometry (TEG 6s). Patients in the TAVR cohort were older and a had lower baseline hemoglobin level than patients in the PCI and SAVR cohorts. The baseline platelet function was similar between the TAVR and PCI cohorts and impaired in the SAVR cohort Figure S1. The baseline hemostatic measures were comparable among cohorts. Regarding the per-patient change from baseline, the TAVR cohort showed an overall more prothrombotic state than the other cohorts, with the most marked differences from the SAVR cohort after intraoperative heparin administration and from the PCI cohorts 6 hours after the procedure. In addition, the ROTEM and TEG parameters were well correlated but not interchangeable. In conclusion, patients who underwent TAVR have a more prothrombotic hemostatic profile than PCI and SAVR patients. These findings question the current guidelines that extrapolate antithrombotic regimens from PCI to TAVR settings.

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.

Impact of Valve Academic Research Consortium 3 (VARC-3) minor access site vascular complications in patients undergoing percutaneous transfemoral transcatheter aortic valve implantation

OBJECTIVES

The aim of this study was to investigate the impact of Valve Academic Research Consortium 3 minor access site vascular complications (VCs) in patients who underwent percutaneous transfemoral (TF) transcatheter aortic valve implantation (TAVI).

METHODS

This single-centre retrospective study included consecutive patients who underwent percutaneous TF-TAVI from 2009 to 2021. A propensity score-matched analysis was performed to compare early and long-term clinical results between patients with VC and without VC (nVC).

RESULTS

A total of 2161 patients were included, of whom 284 (13.1%) experienced access site VC. Propensity score analysis allowed to match 270 patients from the VC group with 727 patients from the nVC group. In the matched cohorts, the VC group showed longer operative times (63.5 vs 50.0 min, P < 0.001), higher operative and in-hospital mortality (2.6% vs 0.7%, P = 0.022; and 6.3% vs 3.2%, P = 0.040, respectively), longer hospital length of stay (8 vs 7 days, P = 0.001) and higher rates of blood transfusion (20.4% vs 4.3%, P < 0.001) and infectious complications (8.9% vs 3.8%, P = 0.003). Overall survival during follow-up was significantly lower in the VC group (hazard ratio 1.37, 95% CI 1.03-1.82, P = 0.031) with 5-year survival rates being 58.0% (95% CI 49.5-68.0%) and 70.7% (95% CI 66.2-75.5%) for the VC and nVC groups, respectively.

CONCLUSIONS

This retrospective study observed that minor access site VCs during percutaneous TF-TAVI can be serious events affecting early and long-term outcomes.

Redo-TAVR: Essential Concepts, Updated Data and Current Gaps in Evidence

Within the last two decades, transcatheter aortic valve replacement (TAVR) has transformed the treatment strategy for symptomatic severe aortic stenosis (AS), representing a less invasive alternative to traditional open-chest surgery. With time, advances in device features, imaging planning, and implantation techniques have contributed to an improvement in safety as well as a reduction in procedural complications. This has led to the expansion of TAVR to lower-risk patients, where TAVR has shown favorable outcomes compared to surgical aortic valve replacement (SAVR). As TAVR expands to younger and lower-risk patients with longer life expectancies, the need for reintervention for failing transcatheter heart valves is expected to increase. Redo-TAVR has gained increasing relevance in the lifetime management of AS as one of the treatment strategies available for structural valve dysfunction (SVD). However, some issues are associated with this approach, including coronary re-access and the risk of coronary obstruction. In this review, we provide essential concepts to properly select candidates for Redo-TAVR, updated data on clinical outcomes and complication rates, and current gaps in evidence.

Evaluation of Hematological Parameters After Transcatheter Aortic Valve Replacement

Although transcatheter aortic valve replacement (TAVR) is safe and effective, mortality and bleeding events post procedure are important. The present study investigated the changes in hematologic parameters to evaluate whether they predict mortality or major bleeding. We enrolled 248 consecutive patients (44.8% male; mean age 79.0 ± 6.4 years) undergoing TAVR. In addition to demographic and clinical examination, blood parameters were recorded before TAVR, at discharge, 1 month and 1 year. Hemoglobin levels before TAVR 12.1 ± 1.8 g/dL, 10.8 ± 1.7 g/dL at discharge, 11.7 ± 1.7 g/dL at first month, 11.8 ± 1.4 g/dL at first year (Hemoglobin values compared with pre-TAVR, P < .001, P = .019, P = .047, respectively). Mean platelet volume (MPV) before TAVR 8.72 ± 1.71 fL, 8.16 ± 1.46 fL at discharge, 8.09 ± 1.44 fL at first month, 7.94 ± 1.18 fL at first year (MPV values compared with pre-TAVR, P < .001, P < .001, P < .001, respectively). Other hematologic parameters were also evaluated. Hemoglobin, platelet count, MPV, and red cell distribution width before the procedure, at discharge, and at the first year did not predict mortality and major bleeding in receiver operating characteristic analysis. After multivariate Cox regression analysis, hematologic parameters were not independent predictors of in-hospital mortality, major bleeding, and death at 1 year after TAVR.

Subclinical Leaflet Thrombosis After Balloon versus Self-Expandable Transcatheter Aortic Valve Implantation

Hypoattenuated leaflet thickening (HALT) has been recognized as one of the complications after transcatheter aortic valve implantation and may promote structural valve degeneration and increase the risk of cerebrovascular events. The 2 main types of available transcatheter heart valves (THVs), the balloon-expandable (BE) and the self-expanding (SE), are interchangeably used in clinical practice despite substantial design differences. There is unclear evidence on whether these 2 different THV models are achieving similar or different rates of subclinical leaflet thrombosis/HALT. A systematic search of electronic databases was conducted to identify studies that reported the incidence of HALT between SE THVs and BE THVs. The Mantel-Haenszel method was used to calculate the 95% confidence interval and pooled risk ratio with a random-effects model. A total of 126 records were identified, of which 22 studies comprising 14,401 patients were included in our final analysis. Among 5,951 patients receiving SE THVs, 194 (3.2%) developed HALT, compared with 8,450 patients receiving BE THVs, of whom 484 (5.7%) developed HALT. There was a statistically significant decrease in the risk of developing HALT in patients receiving SE THVs compared with those receiving BE THVs (risk ratio 0.75, 95% confidence interval 0.59 to 0.95, I² 32%, p = 0.02). In conclusion, could potentially reduce the risk of HALT/subclinical leaflet thrombosis.

Time course of ischemic and bleeding burden in consecutive patients undergoing transcatheter aortic valve replacement (FOCUS-ONE registry)

BACKGROUND AND AIMS

Ischemic or bleeding events might occur after transcatheter aortic valve replacement (TAVR), with the potential to hamper clinical outcomes. This study aimed to characterize the average daily ischemic risks (ADIRs) and the average daily bleeding risks (ADBRs) over 1-year in all consecutive patients undergoing TAVR.

METHODS

ADBR included all bleeding events according to VARC-2 definition, and ADIR included cardiovascular deaths, myocardial infarction and ischemic stroke. ADIRs and ADBRs were assessed within different timeframes post TAVR: acute (0-30 days), late (31-180 days), and very late (>181 days). Generalized estimating equations were used to test the least squares mean differences for the pairwise comparison of ADIRs and ADBRs. Our analysis was performed in the overall cohort and according to antithrombotic strategy (LT-OAC vs No LT-OAC).

RESULTS

Ischemic burden was higher than bleeding burden, independently from the indication to LT-OAC, and in all timeframes examined. In the overall population, ADIRs were three-fold ADBRs (0.0467 [95% CI, 0.0431-0.0506] vs 0.0179 [95% CI, 0.0174-0.0185]; p < 0.001*). While ADIR was significantly higher in the acute phase, ADBR was relatively stable in all timeframes analysed. Of note, in LT-OAC population, OAC + SAPT group showed lower ischemic risk and higher bleeding events compared with OAC alone (ADIR: 0.0447 [95% CI: 0.0417-0.0477] vs 0.0642 [95% CI: 0.0557-0.0728]; p < 0.001*, ADBR 0.0395 [95% CI: 0.0381-0.0409] vs 0.0147 [95% CI: 0.0138-0.0156]; p < 0.001*).

CONCLUSIONS

In patients undergoing TAVR Average daily risk fluctuates over time. However, ADIRs overcome ADBRs in all timeframes, especially in the acute phase and regardless of antithrombotic strategy adopted.

Bleeding Events After Transcatheter Aortic Valve Replacement: JACC State-of-the-Art Review

Transcatheter aortic valve replacement (TAVR) has gained over time a major reduction in procedural complications. Despite this, clinically relevant bleeding still occurs in a non-negligible proportion of patients and adversely affects prognosis. Patients with severe aortic stenosis are at heightened risk for spontaneous bleeding due to advanced age and a high comorbidity burden. Also, procedural factors and antithrombotic management contribute to define individual bleeding susceptibility. Bleeding prevention represents an emerging area for improving patient care. Because of the tight hemorrhagic/ischemic balance, a tailored approach based on individual bleeding-risk profile, such as a less invasive antithrombotic regimen or appropriate diagnostic preprocedural evaluation, should be pursued to avoid bleeding events. This review aims to provide an in-depth overview of bleeding events in the TAVR field, including definitions, timing and the extent of risk, and clinical impact, as well as updates on antithrombotic management and its potential influence on bleeding complications.

Shear-Mediated Platelet Microparticles Demonstrate Phenotypic Heterogeneity as to Morphology, Receptor Distribution, and Hemostatic Function

Objective

Implantable cardiovascular therapeutic devices (CTD) including stents, percutaneous heart valves and ventricular assist devices, while lifesaving, impart supraphysiologic shear stress to platelets resulting in thrombotic and bleeding device-related coagulopathy. We previously demonstrated that shear-mediated platelet dysfunction is associated with downregulation of platelet GPIb-IX-V and αIIbβ3 receptors via generation of platelet-derived microparticles (PDMPs). Here, we test the hypothesis that shear-generated PDMPs manifest phenotypical heterogeneity of their morphology and surface expression of platelet receptors, and modulate platelet hemostatic function.

Approach and Results

Human gel-filtered platelets were exposed to continuous shear stress and sonication. Alterations of platelet morphology were visualized using transmission electron microscopy. Surface expression of platelet receptors and PDMP generation were quantified by flow cytometry. Thrombin generation was quantified spectrophotometrically, and platelet aggregation in plasma was measured by optical aggregometry. We demonstrate that platelet exposure to shear stress promotes notable alterations in platelet morphology and ejection of several distinctive types of PDMPs. Shear-mediated microvesiculation is associated with the differential remodeling of platelet receptors with PDMPs expressing significantly higher levels of both adhesion (α _IIb β ₃ , GPIX, PECAM-1, P-selectin, and PSGL-1) and agonist-evoked receptors (P ₂ Y ₁₂ & PAR1). Shear-mediated PDMPs have a bidirectional effect on platelet hemostatic function, promoting thrombin generation and inhibiting platelet aggregation induced by collagen and ADP.

Conclusions

Shear-generated PDMPs demonstrate phenotypic heterogeneity as to morphologic features and defined patterns of surface receptor alteration, and impose a bidirectional effect on platelet hemostatic function. PDMP heterogeneity suggests that a range of mechanisms are operative in the microvesiculation process, contributing to CTD coagulopathy and posing opportunities for therapeutic manipulation.

Antithrombotic therapy after transcatheter aortic valve replacement

Aortic stenosis is a major valvular disease, which affects prognosis, and its prevalence is increasing due to an aging population. Transcatheter aortic valve replacement (TAVR) is a well-established therapy for symptomatic severe aortic stenosis across the entire risk spectrum, and the number of patients who undergo TAVR is increasing worldwide. Generally, ischemic and bleeding events after TAVR are not rare and can be devastating. Thus, antithrombotic therapy is recommended to prevent thromboembolic events after TAVR. Recently, a lot of randomized control trials have been published on antithrombotic therapy following TAVR, and the situation regarding the optimal antithrombotic regiment following TAVR is dramatically changing. This report reviews the current status and remaining issues in the field of optimal antithrombotic therapy following TAVR and leaflet thrombosis.

The Efficacy and Safety of Direct Oral Anticoagulants versus Standard of Care in Patients without an Indication of Anti-Coagulants after Transcatheter Aortic Valve Replacement: A Meta-Analysis of Randomized Controlled Trials

Transcatheter aortic valve replacement (TAVR) is now considered the mainstay of aortic stenosis management; however, the optimal antithrombotic therapy in patent without indications for an oral anticoagulant (OAC) is yet to be identified. Therefore, we conducted a systematic review and meta-analysis to evaluate the efficacy and safety of direct oral anticoagulant (DOAC) treatment versus the standard of care in patients without indications of OACs after TAVR. We synthesized randomized controlled trials (RCTs) from Web of Science, SCOPUS, EMBASE, PubMed, and Cochrane until 18 August 2022. We used the risk ratio (RR) for dichotomous outcomes with the corresponding 95% confidence interval (CI). We registered our protocol in PROSPERO with ID: CRD42022357027. Three RCTs with 2922 patients were identified. DOACs were significantly associated with higher incidence of all-cause mortality (RR: 1.68 with 95% CI [1.22, 2.30], p = 0.001), mortality due to non-cardiovascular causes (RR: 2.34 with 95% CI [1.36, 4.02], p = 0.002), and the composite outcome of death, myocardial infarction, or stroke (RR: 1.41 with 95% CI [1.13, 1.76], p = 0.002). However, DOACs were associated with decreased incidence of reduced leaflet motion (RLM) (RR: 0.19 with 95% CI [0.09, 0.41], p = 0.0001) and hypoattenuated leaflet thickening (HALT) (RR: 0.50 with 95% CI [0.36, 0.70], p = 0.0001). DOACs were effective to reduce RLM and HALT; however, the clinical effect of this is still controversial. DOACs were associated with worse efficacy and safety outcomes, including all-cause mortality. Further RCTs investigating the optimal antithrombotic regimen after TAVR.

Antithrombotic Therapy After Transcatheter Aortic Valve Replacement: An Overview

Transcatheter aortic valve replacement (TAVR) is an established procedure for the treatment of patients with severe aortic stenosis. The optimal antithrombotic regimen following TAVR, currently unknown and inconsistently applied, is impacted by thromboembolic risk, frailty, bleeding risk, and comorbidities. There is a quickly growing body of literature examining the complex issues underlying antithrombotic regimens post-TAVR. This review provides an overview of thromboembolic and bleeding events following TAVR, summarizes the evidence regarding optimal antiplatelet and anticoagulant use post-TAVR, and highlights current challenges and future directions. By understanding appropriate indications and outcomes associated with different antithrombotic regimens post-TAVR, morbidity and mortality can be minimized in a generally frail and elderly patient population.

Temporal Trends of Transcatheter Aortic Valve Implantation over 12 Years: A High-Volume Single-Center Experience

Transcatheter aortic valve replacement (TAVR) has become the mainstay of treatment for patients with severe AS. Since the TAVR population and patients’ outcomes have dramatically changed over the last decade, updated data regarding contemporary practice and trends are pertinent to clinical use. We performed a retrospective observational analysis of consecutive patient who underwent TAVR for symptomatic severe AS between the years 2009 and 2021 in a single high-volume center. Patients were divided into four equal time groups based on the procedure date (2009−2012, 2013−2015, 2016−2018 and 2019−2021). A total of 1988 patients were included in this study and divided into four groups, with 321, 482, 565 and 620 patients in groups 1−4, respectively. Significant trends were seen in baseline characteristics of a few parameters, including lower age, lower procedural risk and reduced rates of comorbidity (p for trend < 0.0001 for all factors mentioned above). A shift was seen in the procedural technique with lower balloon pre-dilatation and higher device success rates (p for trend < 0.0001). The post-procedural period changed over the years with fewer pacemaker placements (p < 0.0001) and reduced rates of AKI and post-procedural bleed (p value 0.02 and <0.0001, respectively). Furthermore, overall hospital stay was shortened from 7 ± 7.1 days to 2.3 ± 1.7 (p < 0.0001). Finally, patient follow up revealed reduced mortality rates at 30 days (p < 0.0001) and 1 year (p = 0.013). Multivariate regression revealed that a late implantation date was an independent protector from mortality (HR 0.84, p = 0.002). In conclusion, our study demonstrated that TAVR has become a safer practice over the years with reduced rates of morbidity and mortality.

Bleeding risk differences after TAVR according to the ARC-HBR criteria: insights from SCOPE 2

BACKGROUND

The Academic Research Consortium - High Bleeding Risk (ARC-HBR) initiative defined conditions associated with percutaneous coronary intervention (PCI)-related bleeding.

AIMS

We sought to further explore these HBR conditions in the setting of transcatheter aortic valve replacement (TAVR).

METHODS

Patients from the SCOPE 2 trial were stratified by their bleeding risk status based on the ARC-HBR definitions. Baseline and procedural characteristics, as well as key clinical outcomes including Bleeding Academic Research Consortium (BARC) 3-5 bleeding, were compared in ARC-HBR positive (HBR+) and ARC-HBR negative (HBR-) patients.

RESULTS

Of 787 patients randomised in SCOPE 2 and included in this study, 633 were HBR+ (80.4%). Compared with HBR- patients, those HBR+ were older and more frequently presented with diabetes, a history of coronary artery disease, atrial fibrillation, prior cerebrovascular accident, and a Society of Thoracic Surgeons predicted risk of 30-day mortality (STS-PROM) (4.9±2.9% vs 3.3%±2.1%; p<0.0001). In addition, HBR+ patients were more frequently on oral anticoagulation therapy. At 1 year, HBR+ patients had higher rates of all-cause death (12.4% vs 4.3%, respectively, risk difference 8.09%; 95% confidence interval [CI]: 3.76-12.41; p=0.0002); the rates of BARC 3-5 type bleeding were relatively high but not statistically different compared with HBR- patients (7.7% vs 6.1%, risk difference 1.67%; 95% CI: -2.72 to 6.06; p=0.46). Subgroup analyses for bleeding events showed no significant interaction in terms of STS-PROM score, age, or medications.

CONCLUSIONS

The ARC-HBR criteria failed to isolate a subgroup of patients at higher bleeding risk in TAVR patients from a randomised trial. These findings have potential implications, especially for the selection of post-TAVR antithrombotic regimens based on individual bleeding-risk profiles. Specific HBR criteria should be defined for TAVR patients.

Large-bore arterial access closure after transcatheter aortic valve replacement: a systematic review and network meta-analysis

Aims

As the indications to transcatheter aortic valve replacement (TAVR) expand to patients at increasingly lower risk, procedure-related vascular and bleeding complications events must be minimized. We aimed to evaluate the impact of different large-bore arterial access closure devices on clinical outcomes after TAVR.

Methods and results

We searched for papers that reported outcomes according to the type of vascular closure device/technique used after TAVR and performed a Bayesian network meta-analysis (NMA). Fifteen studies involving 9259 patients who underwent access site closure using PROSTAR™ XL percutaneous vascular surgical system (Abbott Vascular, Santa Clara, CA, USA), Perclose ProGlide™ suture-mediated closure system (Abbott), or MANTA^TM vascular closure device (Teleflex, Morrisville, NC, USA) were included. NMA showed MANTA to have the highest likelihood of reducing a primary composite endpoint of intra-hospital death, major vascular complications, and major or life-threatening bleedings [surface under the cumulative ranking curve analysis (SUCRA) 94.8%], but this was mitigated when only randomized clinical trials and propensity-matched cohorts were included (SUCRA 56.1%). The ProGlide showed the highest likelihood to reduce major or life-threatening bleedings, especially with increasing procedural complexity, and the MANTA device to reduce major and minor vascular complications. The ProStar XL device performed poorly in all explored endpoints.

Conclusion

Available evidence summarized through a NMA shows that ProGlide and MANTA devices appear to be both valid vascular closure devices globally and to be the best options to minimize vascular complications and reduce bleeding in patients undergoing TAVR, respectively.

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.

Direct oral anticoagulants or vitamin K antagonists after TAVR: A systematic review and meta-analysis

BACKGROUND

Several patients undergoing transcatheter aortic valve replacement (TAVR) also require oral anticoagulation (OAC) for atrial fibrillation (AF) or deep vein thromboembolism. However, the optimal type of OAC strategy (direct oral anticoagulants, DOACs, or vitamin K antagonists, VKA) is still unclear in this setting.

METHOD

We performed systematic literature research and meta-analysis in PubMed, Medline, and EMBASE databases for studies reporting either all-cause mortality, major/life-threatening bleeding or stroke events.

RESULTS

Ten observational studies and two randomized controlled trials (RCTs) including a total of 29,485 patients were eligible for inclusion. Compared to VKA, DOACs use after TAVR was associated with a modest but significantly lower rates of all-cause mortality (RR 0.90; 95% CI: 0.81-0.99, p-value 0.04) with results mainly driven by observational studies. Cardiovascular mortality (RR 1.03; 95% CI: 0.81-1.30; p-value 0.84), total stroke events (RR 0.97; 95% CI: 0.76-1.23, p-value 0.79), major/life-threatening bleeding (RR 0.93; 95% CI: 0.72-1.21, p-value 0.61) and minor bleeding (RR 0.96; 95% CI: 0.74-1.23; p-value 0.72) were similar between VKA and DOACs.

CONCLUSION

Considering the totality of available evidence, in patients underwent TAVR with a concomitant indication for OAC, DOACs-based strategy is an effective and safe anticoagulation strategy compared to VKA.

Evolving concepts in the management of antithrombotic therapy in patients undergoing transcatheter aortic valve implantation

Thromboembolic and bleeding complications negatively impact recovery and survival after transcatheter aortic valve implantation (TAVI). Particularly, there is a considerable risk of ischaemic stroke and vascular access related bleeding, as well as spontaneous gastro-intestinal bleeding. Therefore, benefit and harm of antithrombotic therapy should be carefully balanced. This review summarizes current evidence on peri- and post-procedural antithrombotic treatment. Indeed, in recent years, the management of antithrombotic therapy after TAVI has evolved from intensive, expert opinion-based strategies, towards a deescalated, evidence-based approach. Besides per procedural administration of unfractionated heparin, this encompasses single antiplatelet therapy in patients without a concomitant indication for oral anticoagulation (OAC); and OAC monotherapy in patients with such indication, mainly being atrial fibrillation. Combination therapy should generally be avoided to reduce bleeding risk, except after recent coronary stenting where a period of dual antiplatelet therapy (aspirin plus P2Y12-inhibitor) or P2Y12-inhibitor plus OAC (in patients with an independent indication for OAC) is recommended to prevent stent thrombosis. This new paradigm in which reduced antithrombotic intensity leads to improved patient safety, without a loss of efficacy, may be particularly suitable for elderly and fragile patients. Whether this holds in upcoming populations of younger and lower-risk patients and in specific populations as patients with subclinical valve thrombosis, is yet to be proven. Finally, whether less intensive or alternative approaches should be also applied for the periprocedural management of the antithrombotic therapy, has to be determined by ongoing and future studies.

Subclinical Leaflet Thrombosis and Anticoagulation After Transcatheter Aortic Valve Replacement: A Review

Importance

Subclinical leaflet thrombosis affects approximately 15% of patients after transcatheter aortic valve replacement (TAVR). The pathophysiology and clinical significance of leaflet thrombosis remain incompletely understood. Defining the optimal management strategy in patients who are asymptomatic, including the role for oral anticoagulation (OAC), is a key challenge for the field.

Observations

Three recent randomized trials have evaluated the role of OAC in patients after TAVR. These studies have confirmed prior observational data suggesting that OAC is effective at prevention of subclinical leaflet thrombosis. Overall, however, OAC does not lead to a clinical benefit over the period studied, and in some patients may be harmful owing to bleeding risk.

Conclusions and Relevance

Strategies for identification of patients in whom the benefit of OAC outweighs the risks are required for optimization of long-term outcome after TAVR. This requires clearer insights into the mechanisms of asymptomatic leaflet thrombosis, its clinical significance, and patient-specific risks of bleeding and structural valve degeneration.

Antithrombotic Therapy Following Transcatheter Aortic Valve Replacement

Due to a large technical improvement in the past decade, transcatheter aortic valve replacement (TAVR) has expanded to lower-surgical-risk patients with symptomatic and severe aortic stenosis. While mortality rates related to TAVR are decreasing, the prognosis of patients is still impacted by ischemic and bleeding complications, and defining the optimal antithrombotic regimen remains a priority. Recent randomized control trials reported lower bleeding rates with an equivalent risk in ischemic outcomes with single antiplatelet therapy (SAPT) when compared to dual antiplatelet therapy (DAPT) in patients without an underlying indication for anticoagulation. In patients requiring lifelong oral anticoagulation (OAC), the association of OAC plus antiplatelet therapy leads to a higher risk of bleeding events with no advantages on mortality or ischemic outcomes. Considering these data, guidelines have recently been updated and now recommend SAPT and OAC alone for TAVR patients without and with a long-term indication for anticoagulation. Whether a direct oral anticoagulant or vitamin K antagonist provides better outcomes in patients in need of anticoagulation remains uncertain, as recent trials showed a similar impact on ischemic and bleeding outcomes with apixaban but higher gastrointestinal bleeding with edoxaban. This review aims to summarize the most recently published data in the field, as well as describe unresolved issues.

Safety of Transcatheter Aortic Valve Replacement in Patients with Aortic Aneurysm: A Propensity-Matched Analysis

Introduction

There is a paucity of data regarding the outcomes of transcatheter aortic valve replacement (TAVR) among patients with thoracic or abdominal aortic aneurysms (AA). Using the Nationwide Inpatient Sample (NIS) database, we explored the safety of TAVR among patients with a diagnosis of AA.

Methods

We queried the National Inpatient Sample database (2012–2017) for hospitalized patients undergoing TAVR, using ICD-9 and ICD-10 codes for endovascular TAVR. Reports show that > 95% of endovascular TAVR in the US is via transfemoral access, so our population are mostly patients undergoing transfemoral TAVR. Using propensity score matching, we compared the trends and outcomes of TAVR procedures among patients with versus without AA.

Results

From a total sample of 29,517 individuals who had TAVR procedures between January 2012 and December 2017, 910 had a diagnosis of AA. In 774 matched-pair analysis, all-cause in-hospital mortality was similar in patients with and without AA OR 0.63 [(95% CI 0.28–1.43), p = 0.20]. The median length of stay was higher in patients with AA: 4 days (IQR 2.0–7.0) versus 3 days (IQR 2.0–6.0) p = 0.01. Risk of AKI [OR 1.01 (0.73–1.39), p = 0.87], heart block requiring pacemaker placement [OR 1.17 (0.81–1.69), p = 0.40], aortic dissection [OR 2.38 (0.41–13.75), p = 0.25], acute limb ischemia [OR 0.46 (0.18–1.16), p = 0.09], vascular complications [OR 0.80 (0.34–1.89), p = 0.53], post-op bleeding [OR 1.12 (0.81–1.57), p = 0.42], blood transfusion [OR 1.20 (0.84–1.70), p = 0.26], and stroke [OR 0.58 (0.24–1.39), p = 0.25] were similar in those with and without AA.

Conclusions

Data from a large nationwide database demonstrated that patients with AA undergoing TAVR are associated with similar in-hospital outcomes compared with patients without AA.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40119-022-00258-6.

Non-Vitamin K Oral Anticoagulant After Transcatheter Aortic Valve Replacement: A Systematic Review and Meta-Analysis

Objective: We aimed to compare non-vitamin K oral anticoagulants (NOACs) with a traditional antithrombotic such as vitamin K antagonist (VKA) and antiplatelet agents in patients after transcatheter aortic valve replacement (TAVR).

Methods: We conducted a search in PubMed, EMBASE, and the Cochrane Library until November 2021 for studies involving comparisons of any type of NOACs, including dabigatran, apixaban, rivaroxaban, and edoxaban, with VKA or antiplatelet agents after TAVR. A comparison of NOACs versus VKA was performed in patients with an indication for oral anticoagulation. In addition, we compared NOACs versus antiplatelet in patients without such indication. We calculated the hazard ratios with 95% confidence intervals (CIs) to determine long-term outcomes. The primary outcome was a combined endpoint consisting of all-cause mortality, stroke, major bleeding, or any related clinical adverse events. Secondary outcomes were all-cause mortality, major bleeding, and stroke, respectively.

Results: A total of 10 studies including 10,563 patients after TAVR were included in this meta-analysis. There were no significant differences in any of the long-term outcomes between the NOAC and VKA groups. Although there were no significant differences in the combined endpoint, major bleeding, or stroke, a significant difference was observed in the all-cause mortality (HR 1.74, 95% CI 1.25–2.43, p = 0.001) between the NOAC and antiplatelet groups.

Conclusion: For patients with an indication for oral anticoagulation after TAVR, NOACs seem to be associated with noninferior outcomes compared with VKA therapy. However, for patients without an indication for oral anticoagulation, NOACs appear to be associated with a higher risk of all-cause death as compared with antiplatelet treatment.

Systematic Review Registration:https://clinicaltrials.gov/, identifier CRD42020155122.

OUP accepted manuscript

Transcatheter aortic valve implantation (TAVI) varies considerably in terms of the procedural approach taken and the hospital length of stay (LoS); both directly affect the cost of care. Our coronary and standard cardiology unit aimed to simplify TAVI (and thus shorten the LoS) while maintaining safety. A shorter LoS would also reduce the burden on hospital resources and free up beds for other patients. Data on 214 consecutive patients undergoing TAVI at a single centre between April 2018 and March 2021 were retrospectively collected. A simplified protocol was implemented in January 2020; patients were stratified by whether they underwent TAVI before or after simplification. All procedural phases were simplified. For cost comparison purposes, the LoS was defined as the number of hospitalization days from admission to discharge. The total hospitalization cost was the sum of the direct and indirect (including reallocated overhead) costs. The LoS fell significantly (by 36%) after TAVI simplification. The times in the coronary care unit (CCU) and standard cardiac unit (SCU) also fell significantly (by 33% and 37% respectively). Patients in the simplified TAVI group were discharged, on average, 6 days after admission. The CCU costs decreased by 31% and the SCU costs by 39%. Transcatheter aortic valve implantation simplification did not compromise safety. Indeed, patients who underwent the simplified procedure seemed to develop fewer complications, especially bleeding. Transcatheter aortic valve implantation simplification significantly reduced the LoS and other costs without compromising patient safety.

Deep Learning in Prediction of Late Major Bleeding After Transcatheter Aortic Valve Replacement

Purpose

Patients and Methods

Results

Conclusion

Use of Direct Oral Anticoagulant and Outcomes in Patients With Atrial Fibrillation after Transcatheter Aortic Valve Replacement: Insights From the STS/ACC TVT Registry

Background

Clinical evidence on the safety and effectiveness of using direct oral anticoagulants (DOACs) in patients with atrial fibrillation after transcatheter aortic valve replacement (TAVR) remains limited. The aim of this study was to investigate the trends and outcomes of using DOACs in patients with TAVR and atrial fibrillation.

Methods and Results

Data from the STS/ACC TVT (Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy) Registry was used to identify patients who underwent successful TAVR with preexisting or incident atrial fibrillation who were discharged on oral anticoagulation between January 2013 and May 2018. Patients with a mechanical valve, valve‐in‐valve procedure, or prior stroke within a year were excluded. The adjusted primary outcome was 1‐year stroke events. The adjusted secondary outcomes included bleeding, intracranial hemorrhage, and death. A total of 21 131 patients were included in the study (13 004 TAVR patients were discharged on a vitamin K antagonist and 8127 were discharged on DOACs.) The use of DOACs increased 5.5‐fold from 2013 to 2018. The 1‐year incidence of stroke was comparable between DOAC‐treated patients and vitamin K antagonist‐treated patients (2.51% versus 2.37%; hazard ratio [HR], 1.00; 95% CI, 0.81–1.23) whereas DOAC‐treated patients had lower 1‐year incidence of any bleeding (11.9% versus 15.0%; HR, 0.81; 95% CI, 0.75–0.89), intracranial hemorrhage (0.33% versus 0.59%; HR, 0.54; 95% CI, 0.33–0.87), and death (15.8% versus 18.2%; HR, 0.92; 95% CI, 0.85–1.00).

Conclusions

In patients with TAVR and atrial fibrillation, DOAC use, when compared with vitamin K antagonists, was associated with comparable stroke risk and significantly lower risks of bleeding, intracranial hemorrhage, and death at 1 year.

Baseline mean platelet volume is a strong predictor of major and life-threatening bleedings after transcatheter aortic valve replacement

BACKGROUND

Bleeding following transcatheter aortic valve replacement (TAVR) has important prognostic implications. This study sought to evaluate the impact of baseline mean platelet volume (MPV) on bleeding events after TAVR.

METHODS AND RESULTS

Patients undergoing TAVR between February 2010 and May 2019 were included. Low MPV (L-MPV) was defined as MPV ≤10 fL and high MPV (H-MPV) as MPV >10 fL. The primary endpoint was the occurrence of major/life-threatening bleeding complications (MLBCs) at one-year follow-up. Among 1,111 patients, 398 (35.8%) had L-MPV and 713 (64.2%) had H-MPV. The rate of MLBCs at 1 year was higher in L-MPV patients compared with H-MPV patients (22.9% vs. 17.7% respectively, p = 0.034). L-MPV was associated with vascular access-site complications (36.2% vs. 28.9%, p = 0.012), early (<30 days) major bleeding (15.6% vs. 9.4%, p<0.01) and red blood cell transfusion >2 units (23.9% vs. 17.5%, p = 0.01). No impact of baseline MPV on overall death, cardiovascular death and ischemic events (myocardial infarction and stroke) was evidenced. Multivariate analysis using Fine and Gray model identified preprocedural hemoglobin (sHR 0.84, 95%CI [0.75-0.93], p = 0.001), preprocedural L-MPV (sHR 1.64, 95%CI [1.16-2.32], p = 0.005) and closure time adenosine diphosphate post-TAVR (sHR 2.71, 95%CI [1.87-3.95], p<0.001) as predictors of MLBCs.

CONCLUSIONS

Preprocedural MPV was identified as an independent predictor of MLBCs one year after TAVR, regardless of the extent of platelet inhibition and primary hemostasis disorders.

Efficacy and safety of antithrombotic therapy with non-vitamin K antagonist oral anticoagulants after transcatheter aortic valve replacement: a systematic review and meta-analysis

Objective:

A meta-analysis was performed to compare the efficacy and safety of antithrombotic therapy with non-vitamin K antagonist oral anticoagulants (NOACs) versus standard care in patients after successful transcatheter aortic valve replacement (TAVR).

Methods:

A systematic search of PubMed, Cochrane Central Register of Controlled Trials, and EMBASE databases and ClinicalTrials.gov website (through 21 October 2020) was performed. Risk ratios (RRs) with 95% confidence intervals (CIs) for all outcomes were calculated using random-effects models.

Results:

Twelve studies (two studies were randomized controlled trials) comprising 6943 patients were included (5299 had indications for oral anticoagulation (OAC) and 1644 had none). No significant differences were found between NOACs and the standard care in the incidences of all stroke, a composite endpoint, and major/life-threatening bleeding. NOACs were associated with lower all-cause mortality than vitamin K antagonists (VKAs) in post-TAVR patients with indications for OAC after more than 1 year of follow-up [RR = 0.64; 95% CI, (0.42, 0.96); p = 0.03], whereas NOACs exhibited poor outcomes than antiplatelet therapy (APT) in patients without indications for OAC [RR = 1.66; 95% CI, (1.12, 2.45); p = 0.01]. In the prevention of valve thrombosis, NOACs and VKAs were not significantly different in patients with indications for OAC [RR = 0.66; 95% CI, (0.24, 1.84); p = 0.43], whereas NOACs were better than APT in patients without indications for OAC [RR = 0.19; 95% CI, (0.04, 0.83); p = 0.03].

Conclusions:

In patients with indications for OAC, post-TAVR antithrombotic therapy with NOACs was more favorable due to its lower all-cause mortality after more than 1 year of follow-up. In those without indications for OAC, NOACs presented poorer outcomes due to its higher all-cause mortality.

Antithrombotic Therapy After Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR) is a treatment option for symptomatic patients with severe aortic stenosis who are candidates for a bioprosthesis across the entire spectrum of risk. However, TAVR carries a risk for thrombotic and bleeding events, underscoring the importance of defining the optimal adjuvant antithrombotic regimen. Antithrombotic considerations are convoluted by the fact that many patients undergoing TAVR are generally elderly and present with multiple comorbidities, including conditions that may require long-term oral anticoagulation (OAC) (eg, atrial fibrillation) and antiplatelet therapy (eg, coronary artery disease). After TAVR among patients without baseline indications for OAC, recent data suggest dual-antiplatelet therapy to be associated with an increased risk for bleeding events, particularly early postprocedure, compared with single-antiplatelet therapy with aspirin. Concerns surrounding the potential for thrombotic complications have raised the hypothesis of adjunctive use of OAC for patients with no baseline indications for anticoagulation. Although effective in modulating thrombus formation at the valve level, the bleeding hazard has shown to be unacceptably high, and the net benefit of combining antiplatelet and OAC therapy is unproven. For patients with indications for the use of long-term OAC, such as those with atrial fibrillation, the adjunctive use of antiplatelet therapy increases bleeding. Whether direct oral anticoagulant agents achieve better outcomes than vitamin K antagonists remains under investigation. Overall, single-antiplatelet therapy and OAC appear to be reasonable strategies in patients without and with indications for concurrent anticoagulation. The aim of the present review is to appraise the current published research and recommendations surrounding the management of antithrombotic therapy after TAVR, with perspectives on evolving paradigms and ongoing trials.

Procedural outcomes in patients with dual versus single antiplatelet therapy prior to transcatheter aortic valve replacement

The impact of uninterrupted dual antiplatelet therapy (DAPT) on bleeding events among patients undergoing transcatheter aortic valve replacement (TAVR) has not been well studied. We conducted an analysis of 529 patients who underwent transfemoral TAVR in our centre and were receiving either DAPT or single antiplatelet therapy (SAPT) prior to the procedure. Accordingly, patients were grouped into a DAPT or SAPT group. Following current guidelines, patients in the SAPT group were switched to DAPT for 90 days after the procedure. The primary endpoint of our analysis was the incidence of bleeding events at 30 days according to the VARC-2 classification system. Any VARC-2 bleeding complications were found in 153 patients (28.9%), while major/life-threatening or disabling bleeding events occurred in 60 patients (11.3%). Our study revealed no significant difference between the DAPT vs. SAPT group regarding periprocedural bleeding complications. Based on multivariable analyses, major bleeding (HR 4.59, 95% CI 1.64–12.83, p = 0.004) and life-threatening/disabling bleeding (HR 8.66, 95% CI 3.31–22.65, p < 0.001) events were significantly associated with mortality at 90 days after TAVR. Both pre-existing DAPT and SAPT showed a comparable safety profile regarding periprocedural bleeding complications and mortality at 90 days. Thus, DAPT can be safely continued in patients undergoing transfemoral TAVR.

An Analysis of the Predictors of Major Bleeding After Transcatheter Aortic Valve Transplantation Using the National Inpatient Sample (2015-2018)

Background Transcatheter aortic valve replacement (TAVR) is now a common procedure to treat and improve quality of life, clinical outcomes, and self-sufficiency in high-risk patients with aortic stenosis, and its use has been expanding rapidly in younger and low-risk populations. The aim of this study was to evaluate the outcomes, trends, and predictors of major bleeding in patients undergoing TAVR. Methodology We utilized the National Inpatient Sample (NIS) data from the year 2015 to 2018. International Classification of Disease 10 codes were utilized to extract data. Baseline characteristics were compared using Pearson's chi-square test for categorical variables and independent samples t-test for continuous variables. A multivariable logistic regression model was used to evaluate the predictors of major bleeding. Propensity matching was done for adjusted analysis to compare outcomes in TAVR with and without major bleeding. The outcomes of interest in this study were (1) predictors of major bleeding after TAVR; (2) in-hospital mortality; and (3) resource utilization in terms of cost and length of stay. Results A total of 34,752 weighted hospitalizations for TAVR were included in the analysis. Of the patients undergoing the procedure, 2,294 (6.6%) had a major bleed while 32,458 (93.3%) did not. At baseline, patients with coagulopathy (odds ratio [OR]: 2.03; 95% confidence interval [CI]: 1.82-2.27), congestive heart failure (OR: 1.26; 95% CI: 1.13-1.40), chronic obstructive pulmonary disease (OR: 1.41; 95% CI: 1.29-1.55), liver disease (OR: 1.96; 95% CI: 1.61-2.39), peripheral vascular disease (OR: 1.29; 95% CI: 1.17-1.43), cerebrovascular disease (OR: 1.22; 95% CI: 1.07-1.38), end-stage renal disease (ESRD) (OR: 2.17; 95% CI: 1.82-2.59), and coronary artery disease (OR: 1.17; 95% Cl: 1.06-1.30) had higher adjusted rates of odds of major bleeding. Patients who had major bleeding had a higher median cost of stay (US$60,326 vs. US$45490) and length of stay (seven vs. three days). Conclusions Mortality is higher in patients with major bleeding, and at baseline, coagulopathy and ESRD are significant predictors of a major bleed in patients undergoing TAVR.

Dual Antiplatelet Therapy vs. Single Antiplatelet Therapy After Transcatheter Aortic Valve Replacement: An Updated Systematic Review and Meta-Analysis

Background: Although mainstream guidelines recommend dual antiplatelet therapy (DAPT) with aspirin and clopidogrel in patients following transcatheter aortic valve replacement (TAVR), it is not evidence-based. We aim to investigate the safety and efficacy of DAPT vs. single antiplatelet therapy (SAPT) after TAVR, and review updated evidence. Methods: We systematically searched PubMed, Embase, and Cochrane for studies comparing DAPT to SAPT after TAVR from inception to November 30, 2020. The primary outcome was major adverse cardiac and cerebrovascular events, including all-cause mortality, cardiovascular death, myocardial infarction (MI), stroke, and major or life-threatening bleeding (LTB). Subgroup analysis was performed according to study type (randomized control trials vs. observational studies) using a fixed-effects model. The quality of evidence was assessed by two scoring systems and GRADE (Grading of Recommendations Assessment, Development, and Evaluation). Results: Twelve studies of 20,766 patients were included in our meta-analysis. Compared with SAPT, DAPT was associated with an increased risk for combined life threatening and major bleeding [OR 1.73 (1.19-2.51), p = 0.004] after TAVR. Such a difference was largely driven by major bleeding [OR 2.29 (1.68-3.11), p < 0.001]. There were no significant differences on major adverse cardiovascular events (MACE) [OR 1.19 (0.99-1.44), p = 0.07], cardiovascular mortality [OR 1.46 (0.93-2.30), p = 0.10], and stroke [OR 0.97 (0.80-1.16), p = 0.71]. Conclusions: Compared with SAPT, post-TAVR DAPT was associated with increased risks of major or life-threatening bleeding without additional benefits of reducing thrombotic events. Future guidelines for post-TAVR antiplatelet strategy are expected to be updated as new high-quality evidence emerges. Systematic Review Registration: PROSPERO, Identifier: CRD42021230075.

Antiplatelet therapy after transcatheter aortic valve implantation: a systematic review and meta-analysis

OBJECTIVES

The aim of this study was to compare antithrombotic regimens after transcatheter aortic valve implantation (TAVI) in patients without an indication for long-term anticoagulation. TAVI is a safe and effective approach for patients with symptomatic severe aortic stenosis and an intermediate-to-high surgical risk. Nevertheless, the antithrombotic regimen after procedure remains controversial.

METHODS

We systematically searched PubMed, Embase and Cochrane databases for interventional studies comparing single antiplatelet therapy with double antiplatelet therapy after TAVI. A meta-analysis was carried out to compare thrombotic and bleeding events between both strategies.

RESULTS

Four randomized clinical trials were included comprising a total of 1085 patients. Our meta-analysis revealed a higher odds ratio (OR) of major bleeding events (pooled OR 2.45, 95% confidence interval (CI) 1.29-4.67; P < 0.01; I2 = 0%) and minor bleeding (pooled OR 1.73, 95% CI 1.12-2.66; P = 0.01; I2 = 0%) for the double antiplatelet therapy group compared with the single antiplatelet therapy group. There was no difference between groups in the risk of stroke (pooled OR 1.04, 95% CI 0.58-1.86; P = 0.91; I2 = 0%), myocardial infarction (pooled OR 2.10, 95% CI 0.75-5.84; P = 0.16, I2 = 0%) and all-cause mortality (pooled OR 1.07, 95% CI 0.63-1.86; P = 0.08; I2 = 0%) after TAVI.

CONCLUSIONS

Our pooled analysis suggests that for patients who underwent TAVI, double antiplatelet therapy compared with single antiplatelet therapy alone increased the risk of bleeding without reducing mortality and ischaemic events.

Usefulness of Antiplatelet Therapy After Transcatheter Aortic Valve Implantation

The rationale for dual antiplatelet therapy (DAPT) after transcatheter aortic valve implantation (TAVI) is to facilitate endothelialization of metallic struts of the transcatheter heart valve and to prevent thrombosis that could lead to thromboembolic events. Based on expert consensus, current societal guidelines recommend DAPT for 1 to 6 months after TAVI with weak evidence. Although the pivotal TAVI trials mandated this regimen, the evidence for the efficacy of DAPT to prevent transcatheter heart valve thrombosis is limited to 3 small trials and a handful of observational studies. Multiple coronary trials have demonstrated that DAPT is associated with increased bleeding in comparison with single antiplatelet therapy, especially in elderly patients. TAVI patients are predominantly elderly and frequently have risk factors that predispose them to bleeding. Herein, we summarize the evidence for antiplatelet therapy after TAVI and explore the theoretical benefit of DAPT to prevent thromboembolic events versus the risk of increased bleeding.

Antithrombotic therapy after transcatheter aortic valve replacement: current perspective

PURPOSE OF REVIEW

Transcatheter aortic valve replacement (TAVR) has expanded as a treatment option for severe aortic stenosis throughout the surgical risk spectrum. Decreasing procedural risk and inclusion of lower risk population has shifted the focus to optimization of postprocedural management and balancing the thrombotic and bleeding complications. In this review, we outline various patient and procedure related factors affecting choice of antithrombotic therapy post TAVR and provide an update of recent development in this area.

RECENT FINDINGS

Multiple studies have confirmed the high incidence of both ischemic and bleeding complications in the early to midterm post-TAVR. In addition, new data has emerged for the role of high resolution computed tomography to detect decreased leaflet mobility and leaflet micro thrombi associated with implications for bioprosthetic valve dysfunction and cerebrovascular events post TAVR. Randomized clinical trials have reported increased bleeding with dual antiplatelet therapy (DAPT) and oral anticoagulation (OAC) plus antiplatelet therapy. These findings suggest that aspirin monotherapy or OAC monotherapy likely provides the appropriate balance for antithrombotic protection and risk of bleeding.

SUMMARY

Majority of patients undergoing TAVR have multiple comorbidities and are at increased risk of ischemic and bleeding complications. In the absence of robust clinical evidence, there is significant variability among guideline recommendations and antithrombotic therapy post TAVR across institutions. The available evidence confirms a high rate of bleeding with more potent and prolonged antithrombotic regimens without a documented benefit for clinical endpoints. The authors favor a conservative anti thrombotic approach and suggest monotherapy with aspirin or systemic anticoagulation based upon an individual's risk of thromboembolic complications. DAPT is reserved for patients with recent stenting and OAC plus aspirin is prescribed for patients with established CAD in the post TAVR setting.

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.

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.

Frailty and Bleeding in Older Adults Undergoing TAVR or SAVR: Insights From the FRAILTY-AVR Study

OBJECTIVES

The aim of this study was to examine the value of frailty to predict in-hospital major bleeding and determine its impact on mid-term mortality following transcatheter (TAVR) or surgical (SAVR) aortic valve replacement.

BACKGROUND

Bleeding complications are harbingers of mortality and major morbidity in patients undergoing TAVR or SAVR. Despite the high prevalence of frailty in this population, little is known about its effects on bleeding risk.

METHODS

A post hoc analysis was performed of the multinational FRAILTY-AVR (Frailty Aortic Valve Replacement) cohort study, which prospectively enrolled older adults ≥70 years of age undergoing TAVR or SAVR. Trained researchers assessed frailty using a questionnaire and physical performance battery pre-procedure and ascertained clinical data from the electronic health record. The primary endpoint was major or life-threatening bleeding during the index hospitalization, and the secondary endpoint was units of packed red blood cells transfused.

RESULTS

The cohort consisted of 1,195 patients with a mean age of 81.3 ± 6.0 years. The incidence of life-threatening bleeding, major bleeding with a clinically apparent source, and major bleeding without a clinically apparent source was, respectively, 3%, 6%, and 9% in the TAVR group and 8%, 10%, and 31% in the SAVR group. Frailty measured using the Essential Frailty Toolset was an independent predictor of major bleeding and packed red blood cell transfusions in both groups. Major bleeding was associated with a 3-fold increase in 1-year mortality following TAVR (odds ratio: 3.40; 95% confidence interval: 2.22 to 5.21) and SAVR (odds ratio: 2.79; 95% confidence interval: 1.25 to 6.21).

CONCLUSIONS

Frailty is associated with post-procedural major bleeding in older adults undergoing TAVR and SAVR, which is in turn associated with a higher risk for mid-term mortality.

Aspirin with or without Clopidogrel after Transcatheter Aortic-Valve Implantation

BACKGROUND

The effect of single as compared with dual antiplatelet treatment on bleeding and thromboembolic events after transcatheter aortic-valve implantation (TAVI) in patients who do not have an indication for long-term anticoagulation has not been well studied.

METHODS

In a randomized, controlled trial, we assigned a subgroup of patients who were undergoing TAVI and did not have an indication for long-term anticoagulation, in a 1:1 ratio, to receive aspirin alone or aspirin plus clopidogrel for 3 months. The two primary outcomes were all bleeding (including minor, major, and life-threatening or disabling bleeding) and non-procedure-related bleeding over a period of 12 months. Most bleeding at the TAVI puncture site was counted as non-procedure-related. The two secondary outcomes were a composite of death from cardiovascular causes, non-procedure-related bleeding, stroke, or myocardial infarction (secondary composite 1) and a composite of death from cardiovascular causes, ischemic stroke, or myocardial infarction (secondary composite 2) at 1 year, with both outcomes tested sequentially for noninferiority (noninferiority margin, 7.5 percentage points) and superiority.

RESULTS

A total of 331 patients were assigned to receive aspirin alone and 334 were assigned to receive aspirin plus clopidogrel. A bleeding event occurred in 50 patients (15.1%) receiving aspirin alone and in 89 (26.6%) receiving aspirin plus clopidogrel (risk ratio, 0.57; 95% confidence interval [CI], 0.42 to 0.77; P = 0.001). Non-procedure-related bleeding occurred in 50 patients (15.1%) and 83 patients (24.9%), respectively (risk ratio, 0.61; 95% CI, 0.44 to 0.83; P = 0.005). A secondary composite 1 event occurred in 76 patients (23.0%) receiving aspirin alone and in 104 (31.1%) receiving aspirin plus clopidogrel (difference, -8.2 percentage points; 95% CI for noninferiority, -14.9 to -1.5; P<0.001; risk ratio, 0.74; 95% CI for superiority, 0.57 to 0.95; P = 0.04). A secondary composite 2 event occurred in 32 patients (9.7%) and 33 patients (9.9%), respectively (difference, -0.2 percentage points; 95% CI for noninferiority, -4.7 to 4.3; P = 0.004; risk ratio, 0.98; 95% CI for superiority, 0.62 to 1.55; P = 0.93). A total of 44 patients (13.3%) and 32 (9.6%), respectively, received oral anticoagulation during the trial.

CONCLUSIONS

Among patients undergoing TAVI who did not have an indication for oral anticoagulation, the incidence of bleeding and the composite of bleeding or thromboembolic events at 1 year were significantly less frequent with aspirin than with aspirin plus clopidogrel administered for 3 months. (Funded by the Netherlands Organization for Health Research and Development; POPular TAVI EU Clinical Trials Register number, 2013-003125-28; ClinicalTrials.gov number, NCT02247128.).

Transcatheter aortic valve replacement: potential use in lower-risk aortic stenosis

INTRODUCTION

The widespread use of transcatheter aortic valve implantation (TAVI) is expanding to low-risk patients. Nevertheless, a low clinical risk does not always correspond to a low procedural risk for the percutaneous approach.

AREAS COVERED

The initial trials on TAVI in low-risk populations had encouraging results, showing non-inferiority in comparison to surgical aortic valve replacement (SAVR). However, the low-risk definition is based on risk score calculators developed for the surgical setting and not including other specific features that are more relevant to TAVI and can affect procedural outcomes. For example, the presence of bicuspid aortic valves, high calcific burden, low coronary height or conduction disturbances is all potentially associated with suboptimal results or even procedural complications. In addition, the lack of longer follow-up prevents us to draw conclusions about long-term outcomes, including data about valve durability and coronary re-access.

EXPERT OPINION

Although current evidence suggest similar results for TAVI and SAVR in low-risk populations, there are some technical and procedural limitations that still need to be addressed in order to close the gap between TAVI and surgery. Optimal, lasting results with a low rate of procedural complications are highly expected in low-risk, otherwise healthy subjects, with potential for longevity.

Bleeding Complications Drive In-Hospital Mortality of Patients with Atrial Fibrillation after Transcatheter Aortic Valve Replacement

Background Atrial fibrillation (AF) is a risk factor for poor postoperative outcome after transfemoral transcatheter aortic valve replacement (TF-TAVR). The present study analyses the outcomes after TF-TAVR in patients with or without AF and identifies independent predictors for in-hospital mortality in clinical practice.

Methods and Results Among all 57,050 patients undergoing isolated TF-TAVR between 2008 and 2016 in Germany, 44.2% of patients (n = 25,309) had AF. Patients with AF were at higher risk for unfavorable in-hospital outcome after TAVR. Including all baseline characteristics for a risk-adjusted comparison, AF was an independent risk factor for in-hospital mortality after TAVR. Among patients with AF, EuroSCORE, New York Heart Association classification class, or renal disease had only moderate effects on mortality, while the occurrence of postprocedural stroke or moderate to major bleeding substantially increased in-hospital mortality (odds ratio [OR] 3.35, 95% confidence interval [CI] 2.61–4.30, p < 0.001 and OR 3.12, 95% CI 2.68–3.62, p < 0.001). However, the strongest independent predictor for in-hospital mortality among patients with AF was severe bleeding (OR 18.00, 95% CI 15.22–21.30, p < 0.001).

Conclusion The present study demonstrates that the incidence of bleeding defines the in-hospital outcome of patients with AF after TF-TAVR. Thus, the periprocedural phase demands particular care in bleeding prevention.

Utility of Three-Dimensional (3D) Modeling for Planning Structural Heart Interventions (with an Emphasis on Valvular Heart Disease)

PURPOSE OF REVIEW

Advanced imaging has played a vital role in the contemporary, rapid rise of structural heart interventions. 3D modeling and printing has emerged as one of the most recent imaging tools and the implementation of 3D modeling is expected to increase with further advances in imaging, print hardware, and materials.

RECENT FINDINGS

3D modeling can be used to educate patients and clinical teams, provide ex vivo procedural simulation, and improve outcomes. Intra-procedural success rates may be improved, and post-procedural complications can be predicted more robustly with appropriate application of 3D modeling. Recent advances in technology have increased the availability of this tool, such that there can be more ready adoption into a routine clinical workflow. Familiarity with 3D modeling and its current utilization and role in structural interventions will help inform how to approach and adapt this exciting new technology.