Thrombus formation after left atrial appendage exclusion using an Amplatzer cardiac plug device

Device related thrombus after left atrial appendage closure: State of the art

Atrial fibrillation (AF), the most common arrhythmia, is a major cause of stroke and systemic embolism. Patients with AF are at higher risk of stroke with the left atrial appendage (LAA) being the most common site for thrombus formation. Although oral anticoagulation (OAC) remains the standard of care for stroke prevention in AF patients, there are still several limitations, including increased risk of bleeding and noncompliance. LAA closure (LAAC) has been found to be non-inferior to OAC in preventing all-cause strokes and systemic embolisms in randomized clinical trials, and is increasingly performed for stroke prevention in patients with nonvalvular AF (NVAF). However, device-related thrombus (DRT) after LAAC and a potentially increased risk of stroke related to DRT were observed in several registered studies, and attract wide concern. This review provides a comprehensive update on the incidence, mechanism, risk factors, prevention, diagnosis, and treatment of DRT after LAAC in patients with NVAF.

An Unusual Case of Left Atrial Mural Thrombus following Aortic Valve Replacement

The left atrial thrombus is a well-known complication of atrial fibrillation and rheumatic mitral valve disease and carries a high risk for systemic thromboembolism. They are generally dissolved after a certain period of optimal anticoagulation. A large thrombus, on the other hand, may persist even with adequate anticoagulation. The surgical removal of a thrombus theoretically poses some risk of systemic embolization, making its management a clinical dilemma. Furthermore, a refractory thrombus is uncommon. Thus, an evidence-based guideline in selecting the optimal therapy is needed. We report a case of a 74-year-old male with atrial fibrillation and a history of unprovoked pulmonary embolism who was incidentally found to have a massive left atrial thrombus shortly after discontinuing warfarin about 4 months following bioprosthetic aortic valve replacement. The thrombus was refractory to anticoagulation posing a clinical management dilemma. This case is interesting in terms of presentation and the approach to diagnosis and treatment.

Changes in Coagulation and Platelet Activation Markers Following Transcatheter Left Atrial Appendage Closure

The recommendations for antithrombotic treatment after left atrial appendage closure (LAAC) remain empirical, and no data exist on the changes in hemostatic markers associated with LACC. The objective of the present study is to determine the presence, degree, and timing of changes in the markers of platelet and coagulation activation after LAAC. Forty-three patients (mean age 76 ± 9 years, 23 men) with atrial fibrillation who underwent successful LACC with the Watchman (n = 27) or Amplatzer Cardiac Plug (n = 16) devices were included in the study. Patients received antiplatelet therapy after LAAC (aspirin + clopidogrel: 27 patients; single antiplatelet therapy with aspirin or clopidogrel: 16 patients). Prothrombin fragment 1+2 and thrombin-antithrombin III were used as markers of coagulation activation, and soluble P-selectin and soluble CD40 ligand were used as markers of platelet activation. Measurements of all hemostatic markers were performed at baseline just before the procedure, followed by days 7, 30, and 180 after LAAC. Prothrombin fragment 1+2 and thrombin-antithrombin levels increased from 0.27 nmol/L and 4.68 ng/ml, respectively, at baseline to peak values of 0.43 nmol/L and 9.76 ng/ml, respectively, at 7 days, partially returning to baseline levels at days 30 and 180 after LAAC (p <0.001 for both markers). No clinical or procedural factors were associated with a greater increase in the markers of coagulation activation after LAAC. Levels of soluble P-selectin and soluble CD40 ligand did not change at any time after LAAC. In conclusion, transcatheter LAAC is associated with significant activation of the coagulation system, yet without evidence of significant platelet activation.

Pulmonary artery perforation and coronary air embolism-two fatal outcomes in percutaneous left atrial appendage occlusion

Percutaneous left atrial appendage (LAA) closure is a routinely performed method to reduce the risk of stroke in patients suffering from atrial fibrillation, when an oral anticoagulation is no longer indicated due to relevant bleeding complications. Currently, the Amplatzer Amulet and the Watchman system are two equally used systems. While there is an acute success rate of more than 95 per cent for this intervention, several minor and major complications such as pericardial effusions, air embolism, vascular lesions in proximity to the heart or even death can occur. Here, we report two cases of very rare fatal outcomes in percutaneous LAA occlusion. Eight hours after deployment of an Amplatzer Amulet a patient died, after the pulmonary trunk was perforated by a hook of the occluder device causing pericardial tamponade. In the second case during final radiological position control of the deployed Watchman occluder air was injected accidentally. The patient immediately died due to coronary air embolism. Forensic autopsies are necessary to solve the cause and manner of death, to evaluate and develop medical devices and to rule out medical malpractice. Thus, a close collaboration of legal medicine and the various cardiologic departments is proposed.

Transesophageal Echocardiography in Atrial Fibrillation

Transesophageal echocardiography (TEE) plays an important role in atrial fibrillation (AF), mainly to detect the presence of left atrial appendage (LAA) thrombus. It is useful in direct current cardioversion (DCC) guidance and for AF ablation and LAA occlusion. With the increasing number of patients affected by AF, the use of TEE will grow and become an important screening modality for LAA thrombus. Future direction includes broader multi-institutional use; further tools to risk stratify patients; and the use of a new spectrum of oral anticoagulants and their cost-effectiveness in patients with AF undergoing DCC, AF ablation, and LAA occlusion.

Assessment of Device-Related Thrombus and Associated Clinical Outcomes With the WATCHMAN Left Atrial Appendage Closure Device for Embolic Protection in Patients With Atrial Fibrillation (from the PROTECT-AF Trial)

Left atrial appendage closure with the WATCHMAN device is an alternative to anticoagulation for stroke prevention in selected patients with atrial fibrillation (AF). LA device-related thrombus (DRT) is poorly defined and understood. We aimed to (1) develop consensus echocardiographic diagnostic criteria for DRT; (2) estimate the incidence of DRT; and (3) determine clinical event rates in patients with DRT. In phase 1 (training), a training manual was developed and reviewed by 3 echocardiographers with left atrial appendage closure device experience. All available transesophageal (TEE) studies in the WATCHMAN left atrial appendage system for embolic protection in patients with atrial fibrillation (PROTECT-AF) trial patients with suspected DRT were reviewed in 2 subsequent phases. In phase 2 (primary blind read), each reviewer independently scored each study for DRT, and final echo criteria were developed. Unanimously scored studies were considered adjudicated, whereas all others were reevaluated by all reviewers in phase 3 (group adjudication read). DRT was suspected in 35 of 485 patients by the site investigator, the echocardiography core laboratory, or both; 93 of the individual TEE studies were available for review. In phase 2, 3 readers agreed on 67 (72%) of time points. Based on phases 1 and 2, 5 DRT criteria were developed. In phase 3, studies without agreement in phase 2 were adjudicated using these criteria. Overall, at least 1 TEE was DRT positive in 27 (5.7%) PROTECT-AF patients. Stroke, peripheral embolism, or cardiac/unexplained death occurred in subjects with DRT at a rate of 3.4 per 100 patient-years follow-up. In conclusion, DRT were identified on at least 1 TEE in 27 PROTECT-AF patients, indicating a DRT incidence of 5.7%. Primary efficacy events in patients with DRT occurred at a rate of 3.4 per 100 patient-years follow-up, intermediate in frequency between event rates previously reported for the overall device and warfarin arms in PROTECT-AF.

Design, Synthesis, andIn VitroAntiplatelet Aggregation Activities of Ferulic Acid Derivatives

In order to discover new compounds with antiplatelet aggregation activities, some ferulic acid (FA) derivatives were designed and synthesized. Thein vitroantiplatelet aggregation activities of these compounds were assessed by turbidimetric test. The results showed that the target compound7fhad potent antiplatelet aggregation activity with its IC5027.6 μmol/L, and7fcan be regarded as a novel potent antiplatelet aggregation candidate.

Left atrial appendage exclusion for atrial fibrillation

Percutaneous left atrial appendage (LAA) closure is being increasingly used as a treatment strategy to prevent stroke in patients with atrial fibrillation (AF) who have contraindications to anticoagulants. Several approaches and devices have been developed in the last few years, each with their own unique set of advantages and disadvantages. In this article, the published studies on surgical and percutaneous approaches to LAA closure are reviewed, focusing on stroke mechanisms in AF, LAA structure and function relevant to stroke prevention, practical differences in procedural approach, and clinical considerations surrounding management.

Left atrial appendage exclusion for prevention of stroke in atrial fibrillation: review of minimally invasive approaches

Stroke prevention is of vital importance in the management of atrial fibrillation (AF), though the proven strategy of systemic anticoagulation for thromboembolic prophylaxis is underutilized for a variety of reasons. The left atrial appendage (LAA) has long been suspected as the principal source of arterial emboli, particularly in nonvalvular AF, and a variety of techniques for its exclusion from the circulation have been developed. This review highlights the history of the LAA as a target of intervention, and the parallel advances in three minimally invasive strategies for its exclusion: percutaneous occlusion of the LAA orifice from within the left atrium, closed-chest ligation via a percutaneous pericardial approach, and minimally invasive thoracoscopic surgery. While further study is necessary, available evidence suggests that effective LAA exclusion is becoming a viable alternative to anticoagulation for stroke prevention in nonvalvular AF.

Complications From Left Atrial Appendage Exclusion Devices

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and has been identified as an independent risk factor for stroke. Prevention of thromboembolic events has been based on oral anticoagulation (OAC) using Vitamin K antagonists (VKA). However, long-term OAC medication is limited by an increased bleeding risk and a low patient compliance. Relying on the observation that the majority of cardiac thrombi originate from the left atrial appendage (LAA) different devices aiming for LAA closure have been proposed. This review will discuss contemporary LAA closure devices with special emphasis on procedure related complications.

Left Atrial Appendage Closure Devices For Stroke Prevention

Cardioembolic stroke is a major cause of morbidity and mortality in patients with atrial fibrillation (AF). The left atrial appendage (LAA) is the prominent source of clot formation. While systemic anticoagulation is the current standard of care, anticoagulants carry many contraindications and possible complications. Techniques for elimination of the LAA are in various stages of development and early clinical use. In the coming years, accumulating data will help guide the management of AF patients at risk of bleeding as well as potentially become first-line therapy to reduce the risk of thromboembolic stroke. The purpose of this article is to review current endovascular and epicardial catheter-based LAA occlusion devices and the clinical data supporting their use.

Surgical options for treatment of atrial fibrillation

If we want to improve the outcomes, increase the success and reduce the complication rate of existing treatment strategies in concomitant and stand-alone atrial fibrillation (AF) procedures, we will have to increase our understanding of the pathophysiology, and of the disease, the limitations of current energy sources and ablation catheters, the different possible lesion sets, as well as improve communication between the electrophysiologist and cardiac surgeon. The technical limitations of percutaneous endocardial ablation procedures and the empirical techniques in surgical AF procedures necessitate new and innovative approaches. Surgeons should aim to improve the quality of the lesion set and minimize the invasiveness of existing techniques. The Maze procedure remains the basis upon which most of the more limited concomitant ablation procedures are and will be designed, but in stand-alone patients, recent progress has directed us towards either a single-step or sequential combined percutaneous endocardial procedure with a thoracoscopic epicardial procedure on the beating heart. A dedicated team of electrophysiologists and cardiothoracic surgeons can now work together to perform AF procedures. This can guide us to determine if there is an additional value of limiting the lesion set of the Maze procedure in concomitant surgery, and of an epicardial access in the treatment of stand-alone AF on the beating heart. If so, we will better understand which energy sources, lesion sets and surgical techniques are able to give us a three-dimensional knowledge and a three-dimensional treatment of AF. As a result, we can expect to obtain a higher single procedure long-term success rate with an acceptable low complication rate.

Risk factors for thrombus formation on the Amplatzer Cardiac Plug after left atrial appendage occlusion

OBJECTIVES

This study sought to identify risk factors for thrombus formation on the Amplatzer Cardiac Plug (ACP) (St. Jude Medical, St. Paul, Minnesota) after left atrial appendage occlusion.

BACKGROUND

Left atrial appendage occlusion with the ACP aims to reduce the risk of embolic stroke and bleeding complications associated with vitamin K antagonists in patients with atrial fibrillation.

METHODS

We performed transesophageal echocardiography before discharge and after 3, 6, and 12 months in 34 patients with atrial fibrillation undergoing ACP implantation and receiving dual antiplatelet therapy. Clinical, echocardiographic, and hemostaseological parameters were retrospectively analyzed to identify risk factors for thrombus formation.

RESULTS

Three patients had thrombi before discharge, 3 more at the 3-month follow-up. No differences were found in left atrial volume, left atrial appendage velocity, spontaneous echo contrast, transmitral gradient, or mitral regurgitation between patients without or with thrombi. CHADS2 (Congestion, Hypertension, Age, Diabetes, and Stroke) score (2.0 ± 1.1 vs. 4.3 ± 1.0), CHA2DS2-VASc (CHADS2 plus Vascular Disease and Sex Category) score (5.2 ± 1.3 vs. 6.8 ± 0.8), and pre-interventional platelet count (215.9 ± 63.9/nl vs. 282.5 ± 84.4/nl) were higher and ejection fraction (50.6 ± 11.4% vs. 39.7 ± 10.6%) lower in those with thrombi. Factor 2, factor 5, or methylenetetrahydrofolate reductase mutations and genetic variants associated with reduced clopidogrel activity were not more frequent in patients with thrombi.

CONCLUSIONS

Transesophageal echocardiography identified 17.6% of patients with thrombus formation on the ACP despite dual antiplatelet therapy. CHADS2 and CHA2DS2-VASc scores, platelet count, and ejection fraction are risk factors for such thrombus formation.

Uncommon delayed and late complications after percutaneous left atrial appendage closure with Amplatzer(®) Cardiac Plug

AIMS

Percutaneous left atrial appendage closure with Amplatzer(®) Cardiac Plug (St. Jude Medical Inc.) for the prevention of stroke in patients with atrial fibrillation is rapidly propagating. We sought to provide additional safety data.

METHODS AND RESULTS

We have screened our database of patients having been treated with Amplatzer(®) Cardiac Plug and found 3 cases with uncommon complications that have not been reported previously. One patient experienced an embolisation of the occluder about 12 months after implantation that potentially resulted from mismatch of occluder size and landing zone. Another patient developed cardiac tamponade 9 days after implantation. This case of delayed effusion was probably not a result of interventional trauma, but might have been provoked by scratching of the inner pericardial membrane. A third patient developed a large thrombus in the left atrium which was considered to be caused by injury of the endothelial wall during implantation. The first two cases could be treated by a percutaneous procedure, the last case by cardiac surgery without any sequelae.

CONCLUSIONS

Complications after left atrial appendage closure not related to a device-related thrombus can occur later after implantation. With appropriate percutaneous or surgical management these complications can be handled without sequelae.

Medical management of connector pin thrombosis with the Amplatzer cardiac plug left atrial closure device

Transcatheter closure of the left atrial appendage with the Amplatzer™ cardiac plug device and double antiplatelet treatment for 3 mo has become an alternative treatment for patients with atrial fibrillation at high embolism risk and contraindications for chronic oral anticoagulation. The inadequate implantation of the left atrial appendage closure device and the discontinuation of double antiplatelet therapy are well-known as factors related to device thrombosis. Nevertheless, device thrombosis after adequate implantation requiring surgical treatment or restarting chronic oral anticoagulation has been reported and can reach 15% of patients. The connector pin thrombosis of the Amplatzer™ cardiac plug, despite a good adherence to antiplatelet treatment, has been recently described as a potential mechanism for device thrombosis. Our clinical case reports the management of this condition for the first time, showing that the early detection of thrombotic complications by transesophageal echocardiography permits solving this serious complication with medical treatment only.

The Amplatzer™ Cardiac Plug 2 for left atrial appendage occlusion: novel features and first-in-man experience

Percutaneous left atrial appendage (LAA) closure is becoming a frequently performed procedure for patients with atrial fibrillation and high haemorrhagic risk. The Amplatzer™ Cardiac Plug (ACP) is one of the most commonly used devices for this purpose. Despite high success rate and low procedure risk associated with the ACP, a second generation of the device is now available. The new ACP has been designed to facilitate the implantation process, improve sealing performance and further reduce the risk of complications. The present report focuses on the novel features of the second generation of the Amplatzer™ Cardiac Plug (ACP 2 or Amulet™) and describes the first-in-man experience.

Percutaneous left atrial appendage closure with the AMPLATZER cardiac plug device in patients with nonvalvular atrial fibrillation and contraindications to anticoagulation therapy

OBJECTIVES

The aim of this study was to evaluate the results associated with left atrial appendage closure (LAAC) with the AMPLATZER Cardiac Plug (ACP) (St. Jude Medical, Minneapolis, Minnesota) in patients with nonvalvular atrial fibrillation and absolute contraindications to anticoagulation therapy.

BACKGROUND

Few data exist on the late outcomes after LAAC in patients with absolute contraindications to warfarin.

METHODS

A total of 52 patients with nonvalvular atrial fibrillation underwent LAAC with the ACP device in 7 Canadian centers. Most patients received short-term (1 to 3 months) dual-antiplatelet therapy after the procedure and single-antiplatelet therapy thereafter. A transesophageal echocardiography was performed in 74% of patients at the 6-month follow-up. No patient was lost to follow-up (≥ 12 months in all patients).

RESULTS

The mean age and median (interquartile range) CHADS2 score were 74 ± 8 years and 3 (2 to 4), respectively. The procedure was successful in 98.1% of the patients, and the main complications were device embolization (1.9%) and pericardial effusion (1.9%), with no cases of periprocedural stroke. At a mean follow-up of 20 ± 5 months, the rates of death, stroke, systemic embolism, pericardial effusion, and major bleeding were 5.8%, 1.9%, 0%, 1.9%, and 1.9%, respectively. The presence of mild peridevice leak was observed in 16.2% of patients at the 6-month follow-up as evaluated by transesophageal echocardiography. There were no cases of device thrombosis.

CONCLUSIONS

In patients with nonvalvular atrial fibrillation at high risk of cardioembolic events and absolute contraindications to anticoagulation, LAAC using the ACP device followed by dual-/single-antiplatelet therapy was associated with a low rate of embolic and bleeding events after a mean follow-up of 20 months. No cases of severe residual leak or device thrombosis were observed at the 6-month follow-up.

[Interventional left atrial appendage occlusion : alternative to oral anticoagulation for stroke prevention in atrial fibrillation]

Stroke prevention in patients with atrial fibrillation is one of the greatest challenges in modern cardiology. Interventional left atrial appendage occlusion is an alternative to oral anticoagulation in patients with non-valvular atrial fibrillation. This procedure is currently used mainly for patients with elevated risk for bleeding complications (HAS-BLED score ≥3) or other contraindications for oral anticoagulation. The novel anticoagulants dabigatran, rivaroxaban and apixaban carry a risk for major bleeding for 2-3% of patients per year. The indications for an interventional left atrial appendage closure are therefore not affected by these substances. Several devices have been developed for this purpose; however, currently only the WATCHMAN® and AMPLATZER® cardiac plug are used in the clinical routine in Germany. The WATCHMAN® device proved to be non-inferior to oral anticoagulation with warfarin in the PROTECT-AF trial in terms of safety and efficacy. These findings are supported by data from registries with up to 5 years follow-up. For the second device currently used in clinical practice, the AMPLATZER® cardiac plug, there is increasing data from registries suggesting comparable safety and efficacy. Both devices necessitate anticoagulation during the first 3-6 months after implantation until endothelialization is completed. Due to the anatomical complexity the implantation should be performed in experienced centers with reduction of the periprocedural risk to <1%. Thus, interventional left atrial appendage occlusion is a valid option to prevent stroke or other thromboembolic events in non-valvular atrial fibrillation especially for elderly patients or those with a history of bleeding complications.

Percutaneous closure of the left atrial appendage for thromboembolic prevention in atrial fibrillation

Atrial fibrillation is a common arrhythmia in clinical practice. It is associated with high morbidity and mortality due to its thromboembolic potential, which makes thromboembolic prevention particularly important. Warfarin has been the first-line therapy for this purpose, but it has various limitations and is often contraindicated or underutilized. The fact that thrombi are frequently located in the left atrial appendage in atrial fibrillation led to the development of percutaneous closure for thromboembolic prevention. This article examines the current evidence on percutaneous closure of the left atrial appendage by reviewing the results of the numerous clinical trials on the technique.

Amplatzer left atrial appendage occlusion: single center 10-year experience

OBJECTIVES

To report a 10-year single center experience with Amplatzer devices for left atrial appendage (LAA) occlusion.

BACKGROUND

Intermediate-term outcome data following LAA occlusion are scarce.

METHODS

Short- and intermediate-term outcomes of patients who underwent LAA occlusion were assessed. All procedures were performed under local aesthesia without transesophageal echocardiography. Patients were discharged on acetylsalicylic acid and clopidogrel for 1-6 months.

RESULTS

LAA occlusion was attempted in 152 patients (105 males, age 72 ± 10 years, CHA2 DS2 -Vasc-score 3.4 ± 1.7, HAS-BLED-score 2.4 ± 1.2). Nondedicated devices were used in 32 patients (21%, ND group) and dedicated Amplatzer Cardiac Plugs were used in 120 patients (79%, ACP group). A patent foramen ovale or atrial septal defect was used for left atrial access and closed at the end of LAA occlusion in 40 patients. The short-term safety endpoints (procedural complications, bleeds) occurred in 15 (9.8%) and the efficacy endpoints (death, stroke, systemic embolization) in 0 patients. Device embolization occurred more frequently in the ND as compared to the ACP group (5 patients or 12% vs. 2 patients or 2%). Mean intermediate-term follow up of the study population was 32 months (range 1-120). Late deaths occurred in 15 patients (5 cardiovascular, 7 noncardiac, 3 unexplained). Neurologic events occurred in 2, peripheral embolism in 1, and major bleeding in 4 patients. The composite efficacy and safety endpoint occurred in 7% and 12% of patients.

CONCLUSION

LAA closure may be a good alternative to oral anticoagulation. This hypothesis needs to be tested in a randomized clinical trial to ensure that all potential biases of this observational study are accounted for.

[Percutaneous exclusion of the left atrial appendage: perspectives]

With its high prevalence and well-known thromboembolic risk, atrial fibrillation (AF) is a crucial component of the 2010-2014 actions plan, ongoing in France to reduce the annual incidence of stroke. The stroke risk is stratified well with the CHA(2)DS(2)-VASc score. With the current guidelines, most patients with AF should be on oral anticoagulant regimen, a treatment recognized as effective but whose bleeding risks limit its use. In clinical practice, warfarin is often not prescribed in patients with high risk of stroke. Thus, the exploration of new ways in preventing thromboembolic events in patients with AF is needed. Beside new more convenient anticoagulant agents, the exclusion of the left atrial appendage recognized as main source of thrombi, may be an alternative in patients with both high risk of thrombotic and haemorrhagic events. Surgical experience showed that the results depend on the quality of the exclusion. For over the past 10 years, several percutaneous exclusion systems of the left atrial appendage have been developed. A randomized study (PROTECT AF) demonstrated the non-inferiority of the percutaneous exclusion in comparison with the warfarin. However, the place of this interventional therapy remains to be clarified, particularly the definition of the target population. This often multidisciplinary approach will have to be accompanied by a reduction of periprocedural complications, increase in rate of complete occlusion, and enough long clinical follow-up to assess the efficiency of this strategy.

Immediate and one-year results in 35 consecutive patients after closure of left atrial appendage with the Amplatzer cardiac plug

INTRODUCTION AND OBJECTIVES

Left atrial appendage closure can be an attractive option for patients with nonvalvular atrial fibrillation and a contraindication to oral anticoagulants, provided that satisfactory results can be achieved during implantation and follow-up.

METHODS

Thirty-five consecutive patients, not eligible for randomized trials with oral anticoagulants, had an Amplatzer occlusion device implanted under general anesthesia. After the first 5 patients, 3-dimensional imaging was incorporated. The results of the implantation and the follow-up were analyzed over a 1-year period.

RESULTS

The mean age was 74.65 (7.61) years, with a CHADS2 score of 2.41 (1.53) and a CHA2DS2-VASc score of 3.17 (1.60). Implantation failed in 1 patient and 5 needed a change in the selected plug size. There were no cardiac complications during the implantation or hospital stay. There was 1 vascular complication (arteriovenous fistula). Transesophageal echocardiography monitoring was performed at 24h, 1, 3, 6, and 12 months and we found 5 thrombi which were resolved with heparin. In the follow-up period of 21.14 (10.09) months, 3 patients aged>80 years died, none of them due to heart problems, and one transient ischemic stroke without further consequences.

CONCLUSIONS

Left atrial appendage closure by an experienced operator can be a treatment option with few complications and with efficient results at>1 year in reducing thromboembolic and hemorrhagic complications, even in very high-risk groups.

Left atrial appendage ligation with single transthoracic port assistance: a study of survival assessment in a porcine model (with videos)

BACKGROUND

Left atrial appendage (LAA) exclusion is a well-known procedure for the prevention of stroke in high-risk patients with atrial fibrillation and contraindication to long-term oral anticoagulant therapy.

OBJECTIVE

To evaluate a natural orifice transluminal endoscopic surgery (NOTES) approach for LAA ligation.

DESIGN

In 4 acute and 6 survival pigs, we performed LAA by using a forward-viewing, single-channel gastroscope and an operative thoracoscope with a 3-mm working channel (introduced through an 8-mm single transthoracic port).

SETTING

Animal laboratory.

INTERVENTIONS

The gastroscope was introduced in the thoracic cavity through an esophageal submucosal tunnel. An end loop introduced through the gastroscope was used to legate the LAA. In the survival experiments, the esophageal mucosa was closed using hemoclips.

MAIN OUTCOME MEASUREMENTS

The time, safety, and feasibility of the procedure were recorded. In the survival experiments, endoscopy and postmortem examination were performed on postoperative day 14.

RESULTS

Creation of a submucosal tunnel and esophagotomy were safely performed in all animals without incidents. The mean time for esophagotomy was 17.0 ± 6.3 minutes. Pericardial dissection and LAA ligation were performed in all animals but 1. The mean time for LAA ligation was 34.4 ± 19.1 minutes. No adverse events occurred during the survival period. Endoscopy showed complete esophageal closure. Postmortem examination revealed pleural adhesions on the site of pericardial dissection, and the LAA was fibrotic with the endoloop in place.

LIMITATIONS

Animal study.

CONCLUSIONS

LAA ligation with single transthoracic trocar assistance is feasible and may be an alternative to anticoagulant therapy or to permanent intracardiac implants in patients with atrial fibrillation.

[Interventional left atrial appendage occlusion. A reasonable alternative to oral anticoagulation - even in the era of the new substances?]

As a potential alternative to long-term oral anticoagulation with vitamin K antagonists in patients with atrial fibrillation, the interventional left atrial appendage occlusion has shown to be non-inferior regarding neurological events. With the new oral direct factor II and factor Xa inhibitors playing an emerging role in stroke prophylaxis, an individual treatment strategy has to be found weighing bleeding and stroke risk against the peri-interventional complication rate based on established risk scores.