Rationale of cerebral protection devices in left atrial appendage occlusion

Case report: three ways to mitigate the risk of embolization during left atrial appendage closure in a patient with a massive and proximal left atrial appendage thrombus

Background

Left atrial appendage (LAA) thrombus is a contraindication for LAA closure (LAAC). However, in selected cases, oral anticoagulants are strictly contraindicated because of a history of life-threatening bleeding, and LAAC remains the only possible therapy to avoid systemic and especially cerebral embolization.

Case summary

We report a case of LAAC despite a massive proximal thrombus in a patient who had an absolute contraindication to anticoagulant therapy, with thorough pre-planning using CT scan, device modelling and thrombus trapping techniques to reduce the risk of systemic embolic events and perform LAAC safely.

Discussion

Although LAAC remains at high risk in this setting, the use of cautious techniques and tools, from pre-procedure planning to systemic embolization prevention systems associated to a precise transoesopheageal echocardiography guiding throughout the procedure, allows it to be performed as safely as possible when no other option is available.

Strategy to optimize PeriproCeduraL AnticOagulation in structural transseptal interventions: Design and rationale of the STOP CLOT trial

BACKGROUND

Both transcatheter edge-to-edge repair (TEER) of mitral regurgitation or left atrial appendage closure (LAAC) require periprocedural anticoagulation with unfractionated heparin (UFH) that is administered either before or immediately after transseptal puncture (TSP). The optimal timing of UFH administration (before or after TSP) is unknown. The Strategy To Optimize PeriproCeduraL AnticOagulation in Structural Transseptal Interventions trial (STOP CLOT Trial) was designed to determine if early anticoagulation is effective in reducing ischemic complications without increasing the risk of periprocedural bleeding.

METHODS

The STOP CLOT trial is a multicenter, prospective, double-blind, placebo-controlled, randomized trial. A total of 410 patients scheduled for TEER or LAAC will be randomized 1:1 either early UFH administration (iv. bolus of 100 units/kg UFH or placebo, given after obtaining femoral vein access and at least 5 minutes prior to the start of the TSP) or late UFH administration (iv. bolus of 100 units/kg UFH or placebo given immediately after TSP). Prespecified preliminary statistical analysis will be performed after complete follow-up of the first 196 randomized subjects. To ensure blinding, a study nurse responsible for randomization and UFH/placebo preparation is not involved in the care of the patients enrolled into the study. The primary study endpoint is a composite of (1) major adverse cardiac and cerebrovascular events (death, stroke, TIA, myocardial infarction, or peripheral embolization) within 30 days post-procedure, (2) intraprocedural fresh thrombus formation in the right or left atrium as assessed with periprocedural transesophageal echocardiography, or (3) occurrence of new ischemic lesions (diameter ≥4 mm) on brain magnetic resonance imaging performed 2 to 5 days after the procedure. The safety endpoint is the occurrence of moderate or severe bleeding complications during the index hospitalization.

CONCLUSIONS

Protocols of periprocedural anticoagulation administration during structural interventions have never been tested in a randomized clinical trial. The Stop Clot trial may help reach consensus on the optimal timing of initiation of periprocedural anticoagulation.

CLINICAL TRIALS REGISTRATION NUMBER

The study protocol is registered at ClinicalTrials.gov, identifier NCT05305612.

Diagnostic and therapeutic pathways for the malignant left atrial appendage: European Heart Rhythm Association physician survey

AIMS

Patients with atrial fibrillation who despite taking oral anti-coagulant therapy (OAT) suffer a stroke or systemic embolism (SSE) without vascular cause or who develop left atrial appendage (LAA) thrombus (LAAT) should be considered as having malignant LAA. The optimal treatment strategy to reduce SSE risk in such patients is unknown. The aim of the study is to investigate the diagnostic and therapeutic pathways for malignant LAA practiced in European cardiac centres.

METHODS AND RESULTS

An 18-item online questionnaire on malignant LAA was disseminated by the European Heart Rhythm Association (EHRA) Scientific Initiatives Committee. A total of 196 physicians participated in the survey. There seems to be high confidence in transoesophageal echocardiography (TEE) imaging, considering LAAT diagnosis. Switching to another direct oral anti-coagulant (DOAC) is the preferred initial step for the treatment of malignant LAA followed by a switch to vitamin K antagonist (VKA), low-molecular-weight heparin, or continued/optimized DOAC dosage, whereas LAA closure is the last option. Left atrial appendage closure is a viable option in patients with embolic stroke despite OAT and no evidence of thrombus at TEE (empty LAA) after comprehensive diagnostic measures to exclude other sources of embolism.

CONCLUSION

This EHRA survey provides a snapshot of the contemporary management of patients diagnosed with malignant LAA. Currently, the majority of patients are treated on an outpatient basis with either shifting from VKA to DOAC or from one DOAC to another. Left atrial appendage closure in this population seems to be reserved for patients with higher bleeding risk or complications of malignant LAA, such as stroke.

Bailout left atrial appendage occluder for pulmonary vein isolation and electrical cardioversion in patients with atrial fibrillation and left atrial appendage thrombus: a pilot study

BACKGROUND

Cardioversion and catheter-based circumferential pulmonary vein isolation (CPVI) are established rhythm control treatment strategies for patients with atrial fibrillation (AF). However, these treatments are contraindicated for AF patients with a left atrial appendage (LAA) thrombus.

METHODS

We conducted the first-in-man case series study to evaluate the feasibility and safety of performing cardioversion or CPVI in AF patients with LAA thrombus immediately after implantation of LAA Occluder (LAAO) in a combined procedure. In our multi-center LAAO registry of 310 patients, 27 symptomatic and drug-refractory AF patients underwent a combined procedure of LAAO and CPVI, among whom 10 (mean age 68 ± 16 years, 6 men) having anticoagulant-resistant LAA thrombus received a bailout procedure of LAAO implantation first then CPVI, and the other 17 patients without LAA thrombus received CPVI first then LAAO for comparison.

RESULTS

The mean CHA₂DS₂-VASc score and HAS-BLED score were comparable between these two groups. In patients with LAA thrombus, we put carotid filters and did a no-touch technique, neither advancing the wire and sheath into the LAA nor performing LAA angiography. After LAAO implantation, the connecting cable was still connected to the occluder when cardioversion was performed. During CPVI, the occluder location was registered in the LA geometry by three-dimensional mapping to guide the catheter not to touch the LAAO. The procedure was successful in all the patients without intra-procedural complications. After a mean follow-up of 1.7 ± 0.7 years, there was no device embolization, peri-device leak ≧ 5 mm or stroke event in both groups. The AF recurrence rate was also similar between the two groups (P = 0.697).

CONCLUSION

We demonstrated that cardioversion or CPVI is doable in symptomatic AF patients with LAA thrombus if LAA was occluded ahead as a bailout procedure.

Percutaneous extraction of a large device-related thrombus on a Watchman™ device: a case report

Background

Left atrial appendage occlusion devices are commonly used to prevent stroke in patients with persistent atrial fibrillation who are unable to tolerate anticoagulation. However, certain patient- and device-related characteristics increase the risk for the development of a device-related thrombus (DRT). The presence of a DRT increases the risk of stroke and should be treated. Management of DRT lacks consensus but is mostly focused on anticoagulation. In patients with large thrombi that need to be managed urgently, percutaneous extraction may be a viable option.

Case summary

In this report, we describe the successful management of a DRT via percutaneous thrombus extraction technology in an 81-year-old woman with a large thrombus attached to a WATCHMAN™ device. The patient initially presented with shortness of breath, and on imaging a pedunculated thrombus was detected. The thrombus was extracted using a Penumbra Lightning 12™ (Penumbra Inc., Alameda, CA, USA) catheter with a Sentinel™ (Boston Scientific, Marlborough, MA, USA) cerebral embolic protection device. The patient had no neurologic sequelae and was started on anticoagulation.

Discussion

Percutaneous thrombectomy can be safely performed to extract large left atrial occlusion DRT that require urgent management, without any neurologic sequelae. We believe this can be used in patients with a large DRT who would not be adequately managed with anticoagulation and in whom surgery is not feasible.

Outcome of left atrial appendage closure using cerebral protection system for thrombosis: no patient left behind

BACKGROUND

Left atrial appendage (LAA) thrombosis increases the risk of stroke and its management has to be assessed. The aim of the present study is to evaluate short and long-term safety and efficacy of a standardized approach of percutaneous LAA closure (LAAC) routinely using a cerebral protection device (CPD) in patients with LAA thrombosis or sludge (LAAT).

METHODS

We prospectively enrolled 14 consecutive patients with atrial fibrillation complicated by LAAT presenting in a high-volume tertiary center. In seven patients (50%) LAAT was found after anticoagulant withdrawal for severe bleedings and in the remaining half LAAT was found despite appropriate anticoagulant therapy. All patients were treated with a standardized interventional approach of LAAC routinely using a CPD and guided by transoesophageal echocardiography.

RESULTS

Mean age was 68 ± 14 years and nine patients (64%) were male. Mean CHA₂ DS₂ -VASc and HAS-BLED scores were 3.3 ± 1.6 and 2.3 ± 1.1, respectively. Six patients (42.8%) presented organized thrombi while eight LAA sludge (57.1%). In 13 patients (92.8%) CPD was positioned through a right radial arterial access. Procedural success was achieved in all patients. In one patient we assisted to embolization of the thrombus during deployment of the device in the absence of neurological consequences. During a mean follow up of 426 ± 307 days, one patient died for non-cardiac cause while no embolic event or major bleeding were reported.

CONCLUSION

In an unselected cohort, LAAC with the systematic use of CPD was a feasible, safe and effective therapeutic option for LAAT both acutely and after long-term follow-up.

Current practice and future prospects in left atrial appendage occlusion

The thromboembolic complications of Atrial fibrillation (AF) remain a major problem in contemporary clinical practice. Despite advances and developments in anticoagulation strategies, therapy is complicated by the high risk of bleeding complications and need for meticulous medication compliance. Over the past few decades, the left atrial appendage has emerged as a promising therapeutic target to prevent thromboembolic events while mitigating bleeding complications and compliance issues. Emerging data indicates that it is a safe, effective and feasible alternative to systemic anticoagulation in patients with non-valvular AF. A number of devices have been developed for endocardial or epicardial based isolation of the left atrial appendage. Increasing experience has improved overall procedural safety and ease while simultaneously reducing device related complication rates. Furthermore, increasing recognition of the non-mechanical advantages of this procedure has led to further interest in its utility for further indications beyond the prevention of thromboembolic complications. In this review, we present a comprehensive overview of the evolution of left atrial appendage occlusion, commercially available devices and the role of this modality in the current management of AF. We also provide a brief outline of the landmark trials supporting this approach as well as the ongoing research and future prospects of left atrial appendage occlusion.

Transcatheter cerebral embolic protection during WATCHMAN procedure in two patients with persistent left atrial appendage thrombus: Case report with review of the literature

Percutaneous left atrial appendage closure (LAAC) has been increasingly used in patients with atrial fibrillation who are poor candidates for long-term oral anticoagulation. The presence of a left atrial appendage (LAA) thrombus is a contraindication for percutaneous LAAC. Despite oral anticoagulation, persistent thrombus is not uncommon. We describe the use of transcatheter cerebral embolic protection with the Sentinel cerebral protection system during LAAC using WATCHMAN in two atrial fibrillation patients who had persistent LAA thrombus despite oral anticoagulation.

1% Aspiration, 99% Perspiration

A 71-year-old man with chronic atrial fibrillation underwent insertion of a left atrial appendage occlusion device. Before release, a large thrombus was noted within the left atrium, attached to the left atrial appendage occluder delivery system. With continuous negative pressure, the device was deployed and thrombus successfully aspirated with no clinical sequelae. (Level of Difficulty: Intermediate.)

Left Atrial Appendage Closure: Prevention and Management of Periprocedural and Postprocedural Complications

Left atrial appendage closure (LAAC) is noninferior to oral vitamin K antagonist therapy for the reduction of nonvalvular atrial fibrillation-related stroke risk. Currently, the procedure is most widely accepted in patients who cannot tolerate oral anticoagulants. This patient population is generally comorbid, making any reduction in procedural complications paramount. LAAC has important complications described in the periprocedural and postprocedural periods. The prevention and management of complications regarding vascular access, transseptal puncture, pericardial effusion, device embolization, stroke, air embolusperidevice leak, device-related thrombus and device erosion/ late pericardial effusion are discussed.

Antithrombotic/Antiplatelet Treatment in Transcatheter Structural Cardiac Interventions-PFO/ASD/LAA Occluder and Interatrial Shunt Devices

Transcatheter interventions enable safe and efficient treatment of various structural heart diseases. However, therapy does not finished with the end of the procedure. Device thrombosis is a possible serious complication. Therefore, careful patient management should include optimal antiplatelet or antithrombotic medication to enhance safe and complete endothelial coverage of the implanted device. In case of thrombus formation careful diagnostic evaluation and prompt treatment is crucial. This paper provides an update to current knowledge and understanding of prevention and management of device related thrombosis.

Impact of a Two-Filter Cerebral Embolic Protection Device on the Complexity and Risk of Transcatheter Aortic Valve Replacement

BACKGROUND

There is a growing use of cerebral protection devices in patients undergoing transcatheter aortic valve replacement (TAVR). We aimed to analyze if the use of these devices itself has an impact on the complexity and the risk of TAVR.

METHODS

Between February 2016 and July 2017, 391 patients underwent transfemoral TAVR with Medtronic CoreValve Evolut R (n = 196) or Edwards Sapien 3 (n = 195). In 39 patients, the Claret Sentinel™ embolic protection device (CS-EPD) was used. Prospectively collected data were retrospectively analyzed, comparing fluoroscopy/operation time, amount of contrast used, vascular events, and postprocedural renal function in TAVR patients with (n = 39) and without (n = 352) CS-EPD.

RESULTS

The CS-EPD was placed through the right radial (n = 35) or brachial (n = 4) artery. Procedural success rate defined as correct deployment and retraction of both filters was 94.9%. No device-related vascular complications occurred. TAVR patients with CS-EPD showed a significantly higher total operation time, total fluoroscopy time, and amount of used contrast (85.4 ± 39.3 vs. 64 ± 29.8 minutes, p = 0.002; 20.7 ± 9.3 vs. 13.7 ± 7 minutes, p ≤ 0.001; 133.7 ± 42.6 vs. 109.7 ± 44.5 mL, p = 0.001). Comparing the initial third of patients receiving a CS-EPD with the last third of CS-EPD cases, procedural time had decreased significantly (102.5 ± 34.9 vs. 67 ± 11.9; p = 0.002). There were no differences in postprocedural renal failure (p = 0.80).

CONCLUSION

Our data add evidence that the application of the CS-EPD is not associated with an additional risk for the patient. Although procedural time and amount of contrast are still higher when using the CS-EPD, there were no device-related complications or increased incidence of renal failure.

Safety and feasibility of interventional left atrial appendage closure without contrast agent

AIMS

Interventional left atrial appendage closure (LAAC) is routinely performed under both echocardiographic and angiographic guiding. However, adverse outcomes, e.g., kidney injury and cerebral embolism, might be associated with injections of contrast agent into the LAA. Therefore, this prospective registry investigated the safety and feasibility of LAAC without the support of angiographic images as the default approach.

METHODS AND RESULTS

This single-centre registry included a total of 46 non-selected, consecutive patients. In the first 25 patients (54%), LAAC with the Amulet device was performed routinely with LAA angiography prior to implantation and after release of the device. The following 21 patients (46%) were treated without the use of contrast agent. The combination of successful implantation and lack of procedural complications was regarded as the primary endpoint. Procedure time, number of recapture manoeuvres, change of device size, compression, leakage, dose area product and late thrombosis on the device were investigated as secondary endpoints. Besides the longer fluoroscopy time and duration of the procedure in the group using angiography, no significant differences could be found. Major complications occurred equally often in both cohorts.

CONCLUSIONS

Interventional LAAC with the Amulet device can be performed safely without the use of contrast agent. This approach might help to enhance the use of LAAC in patients at high risk of contrast-induced nephropathy and procedural stroke.

Cerebral Protection During Catheter Ablation of Ventricular Tachycardia in Patients With Ischemic Heart Disease

Background

Catheter ablation of ventricular tachycardia (VT) is associated with the risk of cerebral embolism. The origin of periprocedural brain embolism in the setting of VT ablation is often unknown and strategies to avoid it are sparse. The aim of this study was to assess the safety and feasibility of an endovascular 2‐filter‐based cerebral protection system (CPS) in left ventricular VT ablation procedures in patients with ischemic heart disease. Furthermore, histopathological correlates of periprocedural embolization were investigated.

Methods and Results

In this pilot study, 11 patients with ischemic heart disease and sustained VT underwent left ventricular catheter ablation under CPS surveillance. The placement of the CPS was conducted before the ablation procedure via the right radial artery. The VT ablation procedure was performed via a combined transaortic and transseptal approach. All VTs were successfully ablated. Placement and retrieval of the CPS was successful and safe in all cases. No periprocedural complications related to the CPS were observed and no periprocedural transient ischemic attack or stroke occurred. Debris captured by the CPS was detected in all patients. Histology revealed that acute thrombus was the most common type of debris (91%), followed by arterial wall tissue (73%) and foreign material (55%). Less frequently found were myocardium (27%), calcification (9%), necrotic core (9%), and valve tissue (9%).

Conclusions

Cerebral protection during VT ablation seems to be safe and feasible. Ablation procedures of VT are associated with embolization of embolic debris, which was found in every patient.

Safety and Efficacy of Protected Cardiac Intervention: Clinical Evidence for Sentinel Cerebral Embolic Protection

Stroke is a well-documented potential risk of structural cardiac interventions. As a result of the far-reaching burden of stroke on patients, caregivers and the healthcare system, new medical interventions and therapies are being developed to help mitigate this risk. One such intervention is the recently FDA-cleared Sentinel™ Cerebral Protection System (Sentinel; Claret Medical, Santa Rosa, CA, USA) designed to capture and remove debris dislodged during transcatheter aortic valve replacement procedures. In the SENTINEL IDE Study, and in a more recent all-comers trial, Sentinel significantly reduced periprocedural strokes by 63 and 70 % respectively. In this paper, we review the growing body of evidence supporting the use of Sentinel in transcatheter aortic valve replacement and other endovascular procedures.

Left atrial appendage occlusion: 2016 in review

A significant body of data has emerged in the area of Percutaneous Left Atrial Appendage Occlusion (LAAO). In this article, we present an overview of the most notable publications along with a review of the most important publications on LAAO in 2016. We also present important historical data such as landmark clinical studies, review of most utilized occlusion devices, and important clinical studies that are underway.