Intracardiac Versus Transesophageal Echocardiographic Guidance for Left Atrial Appendage Occlusion: The LAAO Italian Multicenter Registry

Contrast-free left atrial appendage occlusion in patients using the LAMBRE™ device

BACKGROUND

Advances in imaging have led to procedural optimization of left atrial appendage closure (LAAC). Contrast-free approaches, guided merely by echocardiography, have been established, however data on this topic remains scarce. In this analysis, we assessed contrast-free procedural results with the LAMBRE LAAC device.

METHODS

The multicenter retrospective BoBoMa (Bonn/Bordeaux/Mainz)-Registry included a total of 118 patients that underwent LAAC with LAMBRE devices omitting contrast-dye. Baseline and echocardiographic characteristics as well as intra- and postprocedural complications and outcomes were assessed.

RESULTS

Patients were at a mean age of 77.5 ± 7.5 years with high thromboembolic and bleeding risk (CHADS-VASc-score 4.6 ± 1.4, HAS-BLED-score 3.7 ± 1.0, respectively). Renal function was impaired with a mean glomerular filtration rate (GFR) of 50 ± 22 ml/min. Mean procedural time was 47.2 ± 37.5  minutes with a mean radiation dose of 4.75 ± 5.25 Gy*cm2. Device success, defined as proper deployment in a correct position, was achieved in 97.5% (115/118) of cases with repositioning of the occluder in 7.6% (9/118) and resizing in 3.4% (4/118) of cases. No relevant peri-device leakage (>3 mm) was observed with 42% of occluders being implanted in an ostial position. Periprocedural complications occurred in 6.8% (8/118) of cases, including two cases of device embolization and one case of clinically-relevant pericardial effusion requiring surgical intervention. Other complications included pericardial effusion (2.5%, 3/118) and vascular access site complications (1.7%, 2/118).

CONCLUSION

Echocardiography-guided contrast-free LAAC using the LAMBRE device is safe and feasible. Further prospective studies including the direct comparison of devices as well as imaging techniques are warranted in contrast-free LAAC.

Clinical Protocol for Selecting Intracardiac or Transesophageal Echocardiography-Guided Left Atrial Appendage Occlusion

Intracardiac echocardiography (ICE) has emerged as an alternative to transesophageal echo (TEE) to guide left atrial appendage occlusion (LAAO). We established a protocol to select patients appropriate for ICE guidance. Patients who underwent LAAO with the Watchman or Watchman FLX device (Boston Scientific, Marlborough, Massachusetts) from January 2018 to March 2022 at a large United States center were included. The novel protocol prospectively selected TEE or ICE guidance beginning in January 2020; previous LAAO procedures were retrospectively included. ICE was selected for patients with uninterrupted anticoagulation and appropriate LAA anatomy, renal function, and moderate sedation tolerance. In-hospital outcomes with successful implantation without conversion to TEE guidance, no peridevice leak, and no procedural complications were compared. Composite 1-year outcome included freedom from peridevice leak, device-related thrombus, stroke, and all-cause mortality. A total of 234 patients were included; the mean age was 76.1 ± 8.3 years old, and 42.3% were female. ICE guidance was used for 63 procedures; TEE guidance was used for 171 procedures. For the composite outcome, ICE-guided LAAO was superior to TEE-guided LAAO (risk difference 0.102, 96.8% vs 86.5%, 95% confidence interval 0.003 to 0.203, p = 0.029). In comparison to the TEE-guided group, ICE-guided procedures were shorter (89.1 ± 26.3 vs 99.8 ± 30.0 min, p = 0.0087) with less general anesthesia (26.6% vs 98.8%, p <0.0001). One-year composite adverse outcomes did not differ significantly (80.7% vs 88.9%, p = 0.17). In conclusion, the protocol to select appropriate patients for ICE versus TEE guidance for LAAO is safe and effective. Larger studies are indicated to validate this approach to improve outcomes, shorten procedures, and avoid general anesthesia.

State-of-the-Art of Transcatheter Left Atrial Appendage Occlusion

Left atrial appendage occlusion (LAAO) is an increasingly used alternative to oral anticoagulation in patients with atrial fibrillation, especially in patients with absolute/relative contraindications to these therapies. This review will cover three main aspects of the procedure. In the fist part of the manuscript, we focus on patient selection. We describe three main categories of patients with primary indication to LAAO, namely patients with previous or at a high risk of intracerebral bleeding, patients with a history of major gastrointestinal bleeding and patients with end-stage renal disease and absolute contraindication to novel oral anticoagulants. Some other potential indications are also described. In the second part of the manuscript, we review available devices, trying to highlight different aspects and potential specific advantages. The last section overviews different ways for pre-, intra- and postprocedural imaging, in order to improve procedural safety and efficacy and ameliorate patient outcome. The characteristics of available contemporary devices and the role of imaging in procedural planning, intraprocedural guidance and follow-up are described.

3D Intracardiac Echocardiography for Structural Heart Interventions

Transcatheter structural heart interventions are expanding into more complex spaces including mitral transcatheter edge-to-edge repair, left atrial appendage occlusion, tricuspid transcatheter edge-to-edge repair, mitral/tricuspid valve-in-valve, and perivalvular leak closures. Transesophageal echocardiography (TEE), with concomitant fluoroscopy, has remained the gold standard for many of these interventions. Although three-dimensional intracardiac echocardiography has been used, applications were often limited to guidance for more "simple" procedures such as patent foramen ovale/atrial septal defect closure and/or intraprocedural adjunctive imaging guidance. However, patients with an excessive risk for general anesthesia or contraindications to TEE, including esophageal/gastric disease, cervical/thoracic spinal disease, or coagulopathies, have limited options.

Impact of intracardiac echocardiography versus transesophageal echocardiography guidance on left atrial appendage occlusion procedures: A meta-analysis

BACKGROUND

Intracardiac echocardiography (ICE) is increasingly used during left atrial appendage occlusion (LAAO) as an alternative to transesophageal echocardiography (TEE). The objective of this study is to evaluate the impact of ICE versus TEE guidance during LAAO on procedural characteristics and acute outcomes, as well the presence of peri-device leaks and residual septal defects during follow-up.

METHODS

All studies comparing ICE-guided versus TEE-guided LAAO were identified. The primary outcomes were procedural efficacy and occurrence of procedure-related complications. Secondary outcomes included lab efficiency (defined as a reduction in in-room time), procedural time, fluoroscopy time, and presence of peri-device leaks and residual interatrial septal defects (IASD) during follow-up.

RESULTS

Twelve studies (n = 5637) were included. There were no differences in procedural success (98.3% vs. 97.8%; OR 0.73, 95% CI 0.42-1.27, p = .27; I2  = 0%) or adverse events (4.5% vs. 4.4%; OR 0.81 95% CI 0.56-1.16, p = .25; I2  = 0%) between the ICE-guided and TEE-guided groups. ICE guidance reduced in in-room time (mean-weighted 28.6-min reduction in in-room time) without differences in procedural time or fluoroscopy time. There were no differences in peri-device leak (OR 0.93, 95% CI 0.68-1.27, p = 0.64); however, an increased prevalence of residual IASD was observed with ICE-guided versus TEE-guided LAAO (46.3% vs. 34.2%; OR 2.23, 95% CI 1.05-4.75, p = 0.04).

CONCLUSION

ICE guidance is associated with similar procedural efficacy and safety, but could result in improved lab efficiency (as established by a significant reduction in in-room time). No differences in the rate of periprocedural leaks were found. A higher prevalence of residual interatrial septal defects was observed with ICE guidance.

Intracardiac Echocardiographic Guidance for Structural Heart Procedures: Current Utility as Compared to Transesophageal Echocardiography

Over the past decade, engineering advances in intracardiac echocardiography (ICE) have improved the ability of an imager or interventionalist to guide not only interatrial septal procedures but now commonly left atrial appendage, tricuspid, and mitral procedures. When transesophageal echocardiography (TEE) is not possible because of anatomic limitations, ICE has proved a useful tool to safely complete structural interventions. ICE will play a growing, key role in structural interventions where anatomic factors strongly favor an intracardiac perspective or augment TEE when imaging is suboptimal.

Intracardiac vs Transesophageal Echocardiography for Left Atrial Appendage Occlusion With Watchman FLX in the U.S

BACKGROUND

Intraprocedural imaging is critical for device delivery in transcatheter left atrial appendage occlusion (LAAO). Although pivotal trials of LAAO devices were conducted using transesophageal echocardiography (TEE), intracardiac echocardiography (ICE) is an emerging imaging modality.

OBJECTIVES

This study compared outcomes after ICE- and TEE-guided Watchman FLX implantation in the SURPASS (SURveillance Post Approval AnalySiS Plan) nationwide LAAO registry.

METHODS

Baseline characteristics were compared using chi-square and t-tests. Outcomes were reported in unadjusted and adjusted comparisons via propensity weighting.

RESULTS

Between August 2020 and September 2021, LAAO was attempted in 39,759 patients at 698 sites, including 2,272 cases (5.7%) with ICE and 31,835 (80.0%) with TEE. ICE and TEE patients had similar baseline characteristics and mean procedural times (ICE 82 minutes vs TEE 78 minutes). ICE patients were less likely to receive general anesthesia (54% vs 98%, P < 0.01). Successful device implantation (98.3% vs 97.6%) and complete seal rates at 45 days were similar (n = 25,280; 83% vs 82%). Most adverse event rates were similar; unadjusted mortality rates at 45 days were 1.1% for ICE vs 0.8% for TEE (P = 0.14), and 1.0% vs 0.7% (P = 0.27) in adjusted analyses. Even after adjustment, pericardial effusion rates requiring intervention were significantly higher with ICE at 45 days (1.0% vs 0.5%; P = 0.02). This rate decreased as operators performed more ICE-guided procedures, although 82% of operators had performed <10 ICE-guided procedures overall.

CONCLUSIONS

In the largest comparison to date, ICE use was infrequent. ICE and TEE both achieved high rates of complete LAAO. ICE was associated with significantly higher rates of pericardial effusion requiring intervention.

Intracardiac echocardiography is a promising strategy for guiding closure of the left atrial appendage

Background and Aims

Percutaneous transcatheter left atrial appendage (LAA) closure (LAAC) is an effective approach for preventing ischemic stroke in nonvalvular atrial fibrillation patients. Intracardiac echocardiography (ICE), a new imaging modality, is a promising strategy for guiding LAAC. This review highlights the various strategies for ICE-guided-LAAC as an option for clinical policy.

Methods

A comprehensive literature search was conducted of PubMed, ScienceDirect, Ovid Web of Science, SpringerLink, and other notable databases to identify recent peer-reviewed clinical trials, reviews, and research articles related to ICE and its application in the guidance of LAAC.

Results

Various methods are used to evaluate the spatial structure and dimensions of the LAA. The main techniques for guiding LAAC are transesophageal echocardiography (TEE), cardiac computed tomography (CTA), and ICE. Among these techniques, the advantages of ICE typically include (1) multiangle and real-time assessment of intracardiac structure, (2) a reduction in procedural fluoroscopy, (3) reduced operation time and improved workflow in the catheterization laboratory, and (4) the avoidance of general anesthesia and the early detection of complications.

Conclusion

ICE is a promising strategy for the guidance of LAAC. Among the most advanced and recent technological innovations in cardiovascular imaging in general and volume imaging in particular, ICE offers greater efficacy and safety.

Intra-Cardiac versus Transesophageal Echocardiographic Guidance for Left Atrial Appendage Occlusion with a Watchman FLX Device

This study aimed to compare the peri-procedural success and complication rate within a large registry of intra-cardiac echocardiography (ICE)- vs. transesophageal echocardiography (TEE)-guided left atrial appendage occlusion (LAAO) procedures with a Watchmann FLX device. Data from 772 LAAO procedures, performed at 26 Italian centers, were reviewed. Technical success was considered as the final implant of a Watchmann FLX device in LAA; the absence of pericardial tamponade, peri-procedural stroke and/or systemic embolism, major bleeding and device embolization during the procedure was defined as a procedural success. One-year stroke and major bleeding rates were evaluated as outcome. ICE-guided LAA occlusion was performed in 149 patients, while TEE was used in 623 patients. Baseline characteristics were similar between the ICE and TEE groups. The technical success was 100% in both groups. Procedural success was also extremely high (98.5%), and was comparable between ICE (98.7%) and TEE (98.5%). ICE was associated with a slightly longer procedural time (73 ± 31 vs. 61.9 ± 36 min, p = 0.042) and shorter hospital stay (5.3 ± 4 vs. 5.8 ± 6 days, p = 0.028) compared to the TEE group. At one year, stroke and major bleeding rates did not differ between the ICE and TEE groups. A Watchmann FLX device showed high technical and procedural success rate, and ICE guidance does not appear inferior to TEE.

The Emerging Role of Intracardiac Echocardiography (ICE) in Left Atrial Appendage Closure (LAAC)

PURPOSE OF REVIEW

Intracardiac echocardiography (ICE) has emerged as a powerful imaging tool to guide percutaneous left atrial appendage closure (LAAC). Herein, we review an imaging protocol for ICE-guided LAAC and discuss the evidence for its use.

RECENT FINDINGS

Standardized imaging protocols have been proposed but have not been fully validated. ICE imaging yields similar procedural and clinical outcomes when compared to transesophageal echocardiography (TEE) to guide LAAC. Despite benefits of avoiding general anesthesia, TEE, and multiple physicians for LAAC procedures, ICE imaging remains under-utilized. Novel ICE catheters with 3D imaging capabilities may improve accuracy and efficiency of LAAC device implantation. ICE guidance is feasible, safe, and effective for LAAC. As the field evolves, further studies will be necessary to assess this technological advancement in imaging guidance.

Left Atrial Appendage Occlusion Under Miniaturized Transesophageal Echocardiographic Guidance and Conscious Sedation: Multicenter European Experience

BACKGROUND

Left atrial appendage occlusion (LAAO) procedures are widely guided by standard transesophageal echocardiography (TEE) probes, requiring general anesthesia in most patients. The use of miniaturized TEE probes allows for LAAO guidance under local anesthesia and offers an attractive imaging alternative to standard TEE probes.

OBJECTIVES

The aim of this study was to assess the safety and efficacy of miniaturized TEE probes for procedural guidance of LAAO.

METHODS

Multicenter retrospective observational study of LAAO procedures performed under miniaturized TEE guidance and conscious sedation. The primary efficacy endpoint was technical success. The secondary efficacy endpoint was procedural success (technical success without major periprocedural complications). The safety outcome was a composite of major periprocedural complications.

RESULTS

A total of 546 consecutive LAAO procedures were performed in 5 European centers. Technical success was achieved in 534 (98.0%) patients. Sixteen major periprocedural complications occurred in 15 (2.9%) patients, yielding a procedural success rate of 97.0%. Conversion to general anesthesia was required in 4 (0.7%) patients. Short-term imaging follow-up was available in 422 patients with an incidence of major (>5 mm) TEE-detected residual leaks of 0.7%, complete LAA occlusion of 82.2% on cardiac computed tomography, and device-related thrombus of 5%. As compared with procedural 2-dimensional imaging for device sizing, preprocedural assessment by 3-dimensional imaging resulted in improved technical success (100% vs 95.0%; P < 0.001).

CONCLUSIONS

LAAO under conscious sedation and miniaturized TEE guidance is safe and feasible with a high rate of technical success and a low rate of periprocedural complications.

Impact of Preprocedural Computed Tomography on Left Atrial Appendage Closure Success: A Swiss-Apero Trial Subanalysis

BACKGROUND

The benefit related to the use of preprocedural computed tomography angiography (CCTA) on top of periprocedural echocardiography to plan percutaneous left atrial appendage closure (LAAC) procedures is still unclear.

OBJECTIVES

The authors sought to evaluate the impact of preprocedural CCTA on LAAC procedural success.

METHODS

In the investigator-initiated SWISS-APERO (Comparison of Amplatzer Amulet and Watchman Device in Patients Undergoing Left Atrial Appendage Closure) trial, patients undergoing echocardiography-guided LAAC were randomly assigned to receive the Amulet (Abbott) or Watchman 2.5/FLX (Boston Scientific) device across 8 European centers. According to the study protocol ongoing at the time of the procedure, the first operators had (CCTA unblinded group) or did not have (CCTA blinded group) access to preprocedural CCTA images. In this post hoc analysis, we compared blinded vs unblinded procedures in terms of procedural success defined as complete left atrial appendage occlusion as evaluated at the end of LAAC (short-term) or at the 45-day follow-up (long-term) without procedural-related complications.

RESULTS

Among 219 LAACs preceded by CCTA, 92 (42.1%) and 127 (57.9%) were assigned to the CCTA unblinded and blinded group, respectively. After adjusting for confounders, operator unblinding to preprocedural CCTA remained associated with a higher rate of short-term procedural success (93.5% vs 81.1%; P = 0.009; adjusted OR: 2.76; 95% CI: 1.05-7.29; P = 0.040) and long-term procedural success (83.7% vs 72.4%; P = 0.050; adjusted OR: 2.12; 95% CI: 1.03-4.35; P = 0.041).

CONCLUSIONS

In a prospective multicenter cohort of clinically indicated echocardiography-guided LAACs, unblinding of the first operators to preprocedural CCTA images was independently associated with a higher rate of both short- and long-term procedural success. Further studies are needed to better evaluate the impact of preprocedural CCTA on clinical outcomes.

SCAI/HRS Expert Consensus Statement on Transcatheter Left Atrial Appendage Closure

Exclusion of the left atrial appendage to reduce thromboembolic risk related to atrial fibrillation was first performed surgically in 1949. Over the past 2 decades, the field of transcatheter endovascular left atrial appendage closure (LAAC) has rapidly expanded, with a myriad of devices approved or in clinical development. The number of LAAC procedures performed in the United States and worldwide has increased exponentially since the Food and Drug Administration approval of the WATCHMAN (Boston Scientific) device in 2015. The Society for Cardiovascular Angiography & Interventions (SCAI) has previously published statements in 2015 and 2016 providing societal overview of the technology and institutional and operator requirements for LAAC. Since then, results from several important clinical trials and registries have been published, technical expertise and clinical practice have matured over time, and the device and imaging technologies have evolved. Therefore, SCAI prioritized the development of an updated consensus statement to provide recommendations on contemporary, evidence-based best practices for transcatheter LAAC focusing on endovascular devices.

The Case for Intracardiac Echo to Guide Left Atrial Appendage Closure

Left atrial appendage closure (LAAC) has become a commonly used alternative to anticoagulation for stroke prevention in patients with atrial fibrillation. There is a growing interest in adopting a minimally invasive procedural approach using intracardiac echocardiography (ICE) and moderate sedation. In this article, we review the rational for and the data supporting ICE-guided LAAC and discuss the pros and cons of this approach.

A comparable efficacy and safety between intracardiac echocardiography and transesophageal echocardiography for percutaneous left atrial appendage occlusion

Background

Accumulated clinical studies utilized intracardiac echocardiography (ICE) to guide percutaneous left atrial appendage occlusion (LAAO). However, its procedural success and safety compared to traditional transesophageal echocardiography (TEE) remained elusive. Therefore, we performed a meta-analysis to compare efficacy and safety of ICE and TEE for LAAO.

Methods

We screened studies from four online databases (including the Cochrane Library, Embase, PubMed, and Web of Science) from their inception to 1 December 2022. We used a random or fixed-effect model to synthesize the clinical outcomes and conducted a subgroup analysis to identify the potential confounding factors.

Results

A total of twenty eligible studies with 3,610 atrial fibrillation (AF) patients (1,564 patients for ICE and 2,046 patients for TEE) were enrolled. Compared with TEE group, there was no significant difference in procedural success rate [risk ratio (RR) = 1.01; P = 0.171], total procedural time [weighted mean difference (WMD) = -5.58; P = 0.292], contrast volume (WMD = -2.61; P = 0.595), fluoroscopic time (WMD = -0.34; P = 0.705; I² = 82.80%), procedural complications (RR = 0.82; P = 0.261), and long-term adverse events (RR = 0.86; P = 0.329) in the ICE group. Subgroup analysis revealed that ICE group might be associated with the reduction of contrast use and fluoroscopic time in the hypertension proportion <90 subgroup, with lower total procedure time, contrast volume, and the fluoroscopic time in device type subgroup with multi-seal mechanism, and with the lower contrast use in paroxysmal AF (PAF) proportion ≤50 subgroup. Whereas, ICE group might increase the total procedure time in PAF proportion >50 subgroup and contrast use in multi-center subgroup, respectively.

Conclusion

Our study suggests that ICE may have comparable efficacy and safety compared to TEE for LAAO.

Appropriate Use Criteria of Left Atrial Appendage Closure Devices: Latest Evidences

Atrial fibrillation is the most common arrythmia and it is linked to an increased risk of stroke. Even if anticoagulation therapy reduces the rate of stroke the benefits of this therapy have to been balanced with the increased risk of hemorrhagic event. Left atrial appendage closure is a valid alternative to long term anticoagulation in patients with atrial fibrillation and high hemorrhagic risk. Actually new devices with different features have been tested and introduced progressively in the clinical practice. Improvements preprocedural imaging evaluation and the learning curve of the operators led to percutaneous left atrial appendage closure a safe and effective procedure. A good knowledge of different devices and the technique of implant is necessary for optimization percutaneous left atrial appendage closure and the reduction of complications during the acute phase and follow up.

SCAI/HRS expert consensus statement on transcatheter left atrial appendage closure

Exclusion of the left atrial appendage to reduce thromboembolic risk related to atrial fibrillation was first performed surgically in 1949. Over the past 2 decades, the field of transcatheter endovascular left atrial appendage closure (LAAC) has rapidly expanded, with a myriad of devices approved or in clinical development. The number of LAAC procedures performed in the United States and worldwide has increased exponentially since the Food and Drug Administration approval of the WATCHMAN (Boston Scientific) device in 2015. The Society for Cardiovascular Angiography & Interventions (SCAI) has previously published statements in 2015 and 2016 providing societal overview of the technology and institutional and operator requirements for LAAC. Since then, results from several important clinical trials and registries have been published, technical expertise and clinical practice have matured over time, and the device and imaging technologies have evolved. Therefore, SCAI prioritized the development of an updated consensus statement to provide recommendations on contemporary, evidence-based best practices for transcatheter LAAC focusing on endovascular devices.

Clinical Influence of Ethanol Infusion in the Vein of Marshall on Left Atrial Appendage Occlusion: Results of Feasibility and Safety during Implantation and at 60-Day Follow-Up

BACKGROUND

Ethanol infusion in the vein of Marshall (EI-VOM) has the advantages of reducing the burden of atrial fibrillation (AF), decreasing AF recurrence, and facilitating left pulmonary vein isolation and mitral isthmus bidirectional conduction block. Moreover, it can lead to prominent edema of the coumadin ridge and atrial infarction. Whether these lesions will affect the efficacy and safety of left atrial appendage occlusion (LAAO) has not yet been reported.

OBJECTIVES

To explore the clinical outcome of EI-VOM on LAAO during implantation and after 60 days of follow-up.

METHODS

A total of 100 consecutive patients who underwent radiofrequency catheter ablation combined with LAAO were enrolled in this study. Patients who also underwent EI-VOM at the same period of LAAO were assigned to group 1 (n = 26), and those who did not undergo EI-VOM were assigned to group 2 (n = 74). The feasibility outcomes included intra-procedural LAAO parameters and follow-up LAAO results involving device-related thrombus, a peri-device leak (PDL), and adequate occlusion (defined as a PDL ≤ 5 mm). Safety outcomes were defined as the composites of severe adverse events and cardiac function. Outpatient follow-up was performed 60 days post-procedure.

RESULTS

Intra-procedural LAAO parameters, including the rate of device reselection, rate of device redeployment, rate of intra-procedural PDLs, and total LAAO time, were comparable between groups. Furthermore, intra-procedural adequate occlusion was achieved in all patients. After a median of 68 days, 94 (94.0%) patients received their first radiographic examination. Device-related thrombus was not detected in the follow-up populations. The incidence of follow-up PDLs was similar between the two groups (28.0% vs. 33.3%, p = 0.803). The incidence of adequate occlusion was comparable between groups (96.0% vs. 98.6%, p = 0.463). In group 1, none of the patients experienced severe adverse events. Ethanol infusion significantly reduced the right atrial diameter.

CONCLUSIONS

The present study showed that undergoing an EI-VOM procedure did not impact the operation or effectiveness of LAAO. Combining EI-VOM with LAAO was safe and effective.

Left atrial appendage occlusion

Prevention of stroke represents a goal of primary importance in health systems due to its associated morbidity and mortality. As several patient groups with increased stroke rates have been identified, multiple approaches have been developed and implemented: oral anticoagulation (OAC) for patients with atrial fibrillation, surgical and percutaneous revascularisation in patients with carotid disease, device closure for patients with patent foramen ovale, and now, left atrial appendage occlusion (LAAO) for selected patients with non-valvular atrial fibrillation (NVAF). The latter group of patients are the focus of this review which evaluates the pathophysiology, selection of patients, procedural performance, outcomes of treatment both during and post-procedure, adjunctive therapy, complications, and longer-term outcomes.

Intracardiac Echocardiography to Guide Watchman FLX Implantation: The ICE LAA Study

BACKGROUND

Intracardiac echocardiography (ICE) is increasingly used to guide left atrial appendage closure (LAAC).

OBJECTIVES

The aim of this study was to investigate the efficacy and safety of ICE-guided LAAC with the Watchman FLX device.

METHODS

The ICE LAA (I Can See Left Atrial Appendage) study was a prospective, multicenter study with independent adjudication of echocardiographic data by a core laboratory and clinical events by a clinical events committee. Patients with atrial fibrillation with CHA₂DS₂-VASc scores ≥2 and clinical indications for LAAC were eligible. Preplanning with either cardiac computed tomography or transesophageal echocardiography (TEE) within 7 days prior to LAAC was mandatory. Intraprocedural ICE was carried out from the left atrium. The primary outcome was the rate of significant peri-device leaks (>5 mm) at 45-day TEE.

RESULTS

A total of 100 patients were enrolled. The mean age was 76 ± 8 years, the mean CHA₂DS₂-VASc score was 4.0 ± 1.5, and the mean HAS-BLED score was 2.5 ± 0.9. The incidence of the primary outcome of significant peridevice leak (>5 mm) was 0%; all patients evaluated by TEE at 45 days had effective LAAC. All patients received Watchman FLX devices, and technical success was 100%. The number of devices per case was 1.0 ± 0.1. ICE successfully guided the assessment of device release criteria, including device compression (19.2% ± 7.1%; recommended range: 10%-30%). No subject required conversion to TEE. Procedural complications were 4 access-site bleeds. There was no stroke, transient ischemic attack, systemic embolization, pericardial effusion, device embolization, or device-related thrombus during the procedure or 45-day follow-up.

CONCLUSIONS

ICE can be used to successfully guide LAAC with the Watchman FLX, with excellent procedural success, a high rate of effective LAAC, and minimal periprocedural complications. (I Can See Left Atrial Appendage [ICELAA] Clinical Study; NCT04196335).

Can intracardiac echocardiography completely replace transesophageal echocardiography to guide left atrial appendage closure?-The comparisons of intracardiac echocardiography with transesophageal echocardiography

Left atrial appendage closure (LAAC) is an effective means of preventing ischemic stroke in patients with nonvalvular atrial fibrillation. Transesophageal echocardiography (TEE) is the primary imaging technique to guide LAAC. Its shortcomings, namely the use of general anesthesia and tracheal intubation, inevitably increase procedural risks. Intracardiac echocardiography (ICE), a novel imaging modality for guiding LAAC, has proven more advantageous over TEE due to use of local anesthesia, shortened procedural time, and reduced radiation exposure. This review highlights the differences between ICE and TEE guided LAAC, aiming to provide a reference for clinical decision-making.

Seize the day, …s(e)ize the device: the emerging imaging modality to improve left atrial appendage device sizing

There is still uncertainity about the use of CT-scan for LAAO device sizing. The main reason for this disappointing position is likely to relate to the scarcity of robust data, since there is still difference among institutions with regards how to perform measurement of the devices. Dallan et al. (1) report their own experience on the use of a novel computed tomography angiography-based (CTA) for sizing the Watchman Flex device for left atrial appendage occlusion (LAAO). The authors through the TruPlan software package that a pre-procedural CTA sizing protocol can be applied successfully with ICE guidance and provide excellent procedural outcomes.The applied CTA protocol is safe and can provide high success rates with the WatchmanTM FLX device reducing the number of deployment attempts and reducing the risk of complications. This article is protected by copyright. All rights reserved.

A Comparative Study of Three Imaging Modalities for Size Selection of a Watchman Left Atrial Appendage Closure Device

PURPOSE

To compare the results of computed tomography angiography (CTA), transesophageal echocardiography (TEE), and digital subtraction angiography (DSA) measurements and analyze their accuracy, correlation, and consistency in patients who have successfully undergone left atrial appendage closure (LAAC).

MATERIALS AND METHODS

A total of 157 non-valvular atrial fibrillation (AF) patients who underwent LAAC with Watchman devices were included in the study. The maximum diameter and depth of LAA were recorded using CTA, TEE, and DSA. Correlations and agreements were compared.

RESULTS

The LAAC procedure was performed successfully in all patients using the Watchman device. There was no significant difference between DSA and TEE measurements of the diameter of the LAA ostium. LAA ostium diameter obtained by CTA, however, was greater than that from DSA and TEE. Correlations were good between LAA ostium diameter measured by TEE, CTA, and DSA and Watchman device size. DSA measurements and actual device size showed the widest limits of agreement, followed by TEE; CTA measurements showed the narrowest limits of agreement. For LAA depth measurements, mean CTA measurements were higher than those of TEE and DSA. There was no significant difference in depth measurements among the three imaging modalities.

CONCLUSION

CTA, TEE, and DSA measurements exhibited good correlations with Watchman device size. The ostium diameter and depth of the LAA measured by CTA were greater than those measured by TEE and DSA. The relevance and concordance of CTA measurements were the strongest.

The Case for Intracardiac Echo to Guide Left Atrial Appendage Closure

Left atrial appendage closure (LAAC) has become a commonly used alternative to anticoagulation for stroke prevention in patients with atrial fibrillation. There is a growing interest in adopting a minimally invasive procedural approach using intracardiac echocardiography (ICE) and moderate sedation. In this article, we review the rational for and the data supporting ICE-guided LAAC and discuss the pros and cons of this approach.

Intracardiac Echocardiography-Guided Left Atrial Appendage Closure With a Novel Foam-Based Conformable Device: Safety and 1-Year Outcomes

OBJECTIVES

This is a first report of the safety and 1-year outcomes of left atrial appendage closure (LAAC) using a novel foam-based conformable device, guided by intracardiac echocardiography (ICE).

BACKGROUND

Limitations of current transcatheter LAAC devices include the need for precise coaxial delivery into the left atrial appendage (LAA), potential for traumatic implantation, incomplete LAA seal, and device-related thrombus.

METHODS

The device (Conformal Left Atrial Appendage Seal, Conformal Medical Inc) is a self-expanding occluder consisting of a cylindrical nitinol endoskeleton with low-profile anchor barbs around the midpoint, covered with a porous foam cup. In a prospective single-center series, under conscious sedation, the device was delivered under fluoroscopic and ICE guidance. After positioning, a transesophageal echocardiography probe was placed to confirm ICE findings before device release. After closure, dual antiplatelet therapy was administered for 6 months. Follow-up imaging was planned for 45 days and 6 and 12 months.

RESULTS

A total of 15 patients (age 71.3 ± 10.8 years, 33% men, CHA₂DS₂-VASc 4.1 ± 1.7, HAS-BLED 3.4 ± 1.4) underwent LAAC, 100% successfully. There were no procedure/device-related complications requiring intervention. Asymptomatic pericardial effusion occurred in 2 patients. The 45-day, 6-month, and 12-month follow-up imaging in 11, 9, and 13 patients, respectively, revealed adequate LAA seal (leak ≤5 mm) in all patients; device-related thrombus was detected in 1 patient at 6 months. Over 1-year follow-up, there were no ischemic strokes and 1 minor bleed. Nonprocedure-/device-related death occurred in 2 patients.

CONCLUSIONS

This first report indicates that LAAC with the conformable implant guided by ICE imaging is feasible with encouraging 1-year clinical outcomes. (The Conformal Prague Study; NCT04193826).

Outcome and safety of intracardiac echocardiography guided left atrial appendage closure within zero-fluoroscopy atrial fibrillation ablation procedures

BACKGROUND

Simultaneous atrial fibrillation (AF) catheter ablation and left atrial appendage closure (LAAC) is sometimes recommended for both rhythm control and stroke prevention. However, the advantages of intracardiac echocardiography (ICE) guidance for this combined procedure have been scarcely reported. We aim to evaluate the clinical outcomes and safety of ICE guided LAAC within a zero-fluoroscopy catheter ablation procedure.

METHODS AND RESULTS

From April 2019 to April 2020, 56 patients with symptomatic AF underwent concomitant catheter ablation and LAAC. ICE with a multi-angled imaging protocol mimicking the TEE echo windows was used to guide LAAC. Successful radiofrequency catheter ablation and LAAC were achieved in all patients. Procedure related adverse event rate was 3.6%. During the 12-month follow-up, 75.0% of patients became free of arrhythmia recurrences and oral anticoagulants were discontinued in 96.4% of patients. No ischemic stroke occurred despite two cases of device-related thrombosis versus an expected stroke rate of 4.8% based on the CHA₂ DS₂ -VASc score. The overall major bleeding events rate was 1.8%, which represented a relative reduction of 68% versus an expected bleeding rate of 5.7% based on the HAS-BLED score of the patient cohort. The incidence of iatrogenic atrial septal defect secondary to a single transseptal access dropped from 57.9% at 2 months to 4.2% at 12 months TEE follow-up.

CONCLUSION

The combination of catheter ablation and LAAC under ICE guidance was safe and effective in AF patients with high stroke risk. ICE with our novel protocol was technically feasible for comprehensive and systematic assessment of device implantation. This article is protected by copyright. All rights reserved.

Patient selection, procedural planning and interventional guidance for non-valvular structural intervention

Percutaneous non-valvular structural interventions, encompassing patent foramen ovale, atrial or ventricular septal defect closure and left atrial appendage closure, are usually performed in young and healthy patients and represent a valid alternative to pharmacological or surgical interventions. In order to minimize procedural and device related complications, a careful pre-procedural planning together with an accurate intra-procedural imaging are crucial to improve patient's outcome. In this article, we review currently available evidence on patient selection, procedural planning and interventional guidance helping physician to determine who will derive the most benefit from the procedure.

Left Atrial Appendage Occlusion for Stroke Prevention in Nonvalvular Atrial Fibrillation

The majority of embolic strokes in patients with nonvalvular atrial fibrillation are caused by thrombi in the left atrial appendage. It is projected that strokes related to atrial fibrillation will markedly increase in the future unless effective mitigation strategies are implemented. Systemic anticoagulation has been known to be highly effective in reducing stroke risk in patients with atrial fibrillation. However, bleeding complications and nonadherence are barriers to effective anticoagulation therapy. Surgical and percutaneous left atrial appendage occlusion devices are nonpharmacologic strategies to mitigate the challenges of drug therapy. We present a contemporary review of left atrial appendage occlusion for stroke prevention in nonvalvular atrial fibrillation. A thorough review of the history of surgical and percutaneous left atrial appendage occlusion devices, recent trials, and US Food and Drug Administration milestones of current left atrial appendage occlusion devices are discussed.

[Left atrial appendage closure : Current data and future developments]

Catheter-based left atrial appendage closure (LAAC) is currently a potential treatment option for stroke prevention in patients with atrial fibrillation and high risk for stroke/embolism as well as high bleeding risk. Due to improvements in LAAC devices, advances in implantation techniques and growing experience of the interventional teams, the safety profile of LAAC has significantly improved in recent years. These developments have led to a currently comprehensive exploration of novel indications for LAAC, such as patients with atrial fibrillation and a low risk of hemorrhage, patients with atrial fibrillation after pulmonary vein ablation or patients after electrical isolation of the left atrial appendage. The treatment principle of closure of the left atrial appendage is supported by new data, which show the effectiveness of surgical closure of the left atrial appendage with respect to a reduction of the risk of stroke, at least partly in conjunction with oral anticoagulation during cardiological surgical interventions. Currently, the application in the clinical practice is reflected by a high degree of active studies. These randomized studies are testing the use of LAAC in new fields of application and together with the new developments in implantation techniques should define the optimal future use of the methods for the clinical practice. The current potential indications for the LAAC procedure, ongoing randomized clinical trials and advances in device development, implantation planning and technique as well as future developments in the field of LAAC treatment are summarized and discussed in this review article.

Impact of Echocardiographic Guidance on Safety and Efficacy of Left Atrial Appendage Closure: An Observational Study

OBJECTIVES

The aim of this study was to evaluate the impact of echocardiographic guidance on the safety and efficacy of left atrial appendage closure (LAAC).

BACKGROUND

Expert consensus documents recommend intraprocedural imaging by means of either transesophageal echocardiography or intracardiac echocardiography to guide LAAC. However, no evidence exists that intraprocedural echocardiographic guidance in addition to fluoroscopy improves the safety and efficacy of LAAC.

METHODS

Consecutive LAAC procedures performed at a high-volume center between January 2009 and October 2020 were stratified on the basis of intraprocedural imaging modalities, including fluoroscopic guidance (FG) only or intraprocedural echocardiographic guidance (EG) in addition to fluoroscopy. The primary safety endpoint was the composite of procedure-related complications occurring within 7 days after the procedure. Technical success at 7 days and at follow-up were secondary endpoints.

RESULTS

Among 811 LAAC procedures, 549 (67.7%) and 262 (32.3%) were assigned to the FG and EG groups, respectively. After adjusting for confounders, EG remained associated with a lower rate of the primary safety endpoint (3.4% vs 9.1%; P = 0.004; adjusted odds ratio [OR]: 0.31; 95% CI: 0.11-0.90; P = 0.030). Technical success trended higher at 7 days (92.1% vs 87.2%; P = 0.065; adjusted OR: 1.68; 95% CI: 0.95-3.01; P = 0.079) and was significantly improved with EG compared with FG (87.6% vs 79.9%; P = 0.018; OR: 4.06; 95% CI: 1.60-10.27; P = 0.003) after a median follow-up period of 4.9 months (interquartile range: 3.4 months-6.2 months).

CONCLUSIONS

In a large cohort of consecutive LAACs, the use of intraprocedural echocardiography to guide intervention in addition to standard fluoroscopy was associated with lower risks for procedural complications and higher mid-term technical success rates.

Clinical Impact of Preprocedural CT-Based 3D Computational Simulation of Left Atrial Appendage Occlusion with Amulet

Aims

Standard of care (SoC) device size selection with transoesophageal echocardiography (TOE) and computed tomography (CT) in LAAO can be challenging due to a certain degree of variability at both patient and device levels. The aim of this study was to prospectively evaluate the clinical impact of 3D computational modelling software in the decision-making of left atrial appendage occlusion (LAAO) with Amplatzer Amulet.

Methods and Results

SoC preprocedural assessments as well as CT-based 3D computational simulations (FEops) were performed in 15 consecutive patients scheduled for LAAO with Amulet. Preprocedural device size selection and degree of confidence were determined after SoC and after FEops-based assessments and compared to the implanted device. FEops-based preprocedural assessment correctly selected the implanted device size in 11 out of 15 patients (73.3%), compared to 7 patients (46.7%) for SoC-based assessment. In 4 patients (26.7%), FEops induced a change in device size initially selected by SoC. In the 7 patients (46.7%) in which FEops confirmed the SoC device size selection, the degree of confidence of the size selection increased from 6.4 ± 1.4 for SoC to 8.1 ± 0.7 for FEops. One patient (6.7%) could not be implanted for anatomical reason, as correctly identified by FEops.

Conclusions

Preprocedural 3D computational simulation by FEops impacts Amulet size selection in LAAO compared to TOE and CT-based SoC assessment. Operators could consider FEops computational simulation in their preprocedural device size selection.

Intracardiac echocardiography for guidance of transcatheter left atrial appendage occlusion: An expert consensus document

Transcatheter left atrial appendage occlusion (LAAO) is an increasingly used alternative to oral anticoagulation in selected patients with atrial fibrillation. Intraprocedural imaging is a crucial for a successful intervention, with transesophageal echocardiography (TEE) as the current gold standard. Since some important limitations may affect TEE use, intracardiac echocardiography (ICE) is increasingly used as an alternative to TEE for guiding LAAO. The lack of a standardized imaging protocol has slowed the adoption of ICE into clinical practice. On the basis of current research and expert consensus, this paper provides a protocol for ICE support of left atrial appendage occlusion.

Role of Intracardiac Echography for Transcatheter Occlusion of Left Atrial Appendage

Left atrial appendage closure (LAAC) is an increasingly common procedure for patients with nonvalvular atrial fibrillation and contraindications to long-term anticoagulation. Traditionally, LAAC has been performed under transesophageal echocardiography (TEE) guidance. Although most operators have become experienced and comfortable with TEE-guided appendage closure, there has been a growing interest in the use of intracardiac echocardiography (ICE) for LAAC. This article describes the rationale and technique for ICE-guided LAAC.

Three-Dimensional Echocardiographic Left Atrial Appendage Volumetric Analysis

BACKGROUND

Left atrial appendage (LAA) echocardiographic assessment is difficult because of the complex shape and relatively small size of the LAA. Three-dimensional (3D) echocardiographic imaging can overcome the limitations of two-dimensional imaging. Pulsed-wave Doppler is the only currently standard LAA functional parameter. The aim of this study was to test a new approach for 3D echocardiographic volumetric analysis to obtain LAA ejection fraction (EF), its size and shape.

METHODS

Transesophageal two-dimensional and 3D LAA images were prospectively obtained in 159 consecutive patients. LAA volumes were measured from 3D echocardiographic images using available software. Pulsed-wave Doppler was considered the reference value for LAA function and was used for comparison with LAA EF. Comparison with cardiac computed tomography was performed in a subgroup of 32 patients. Comparisons included linear regression and Bland-Altman analyses. Repeated measurements were performed to assess measurement variability.

RESULTS

Nine patients were excluded because of suboptimal image quality (94% feasibility). Three-dimensional LAA calculated EF was in good agreement with LAA pulsed-wave measurements. Three-dimensional morphologic evaluation showed that 43% of the patients had "chicken wing," 33% "cactus," 19% "windsock," and 5% cauliflower shapes. At the time of data acquisition, patients with atrial fibrillation had nonsignificantly larger LAA end-systolic and end-diastolic volumes, leading to lower calculated EFs. Three-dimensional echocardiographic LAA end-systolic volumes were in good agreement with cardiac computed tomography (r = 0.75), with small biases (mean, -2.5 ± 3.9 ml). Reproducibility was better for larger LAA volumes.

CONCLUSIONS

A novel 3D echocardiographic approach can determine the geometry, size, and function of the LAA. A new parameter, LAA EF, provides functional quantitation.

Intracardiac echocardiography-guided implantation of the Watchman FLX left atrial appendage closure device

BACKGROUND

The next-generation Watchman FLX left atrial appendage closure (LAAC) device has: (1) an atraumatic closed distal end, (2) reduced height, (3) a recessed screw hub to decrease device-related thrombus (DRT), (4) two rows of J-shape anchors so redeployment is possible after full recapture, and (5) ability to treat a greater size range of LAA ostia.

OBJECTIVE

To report, for the first time, the feasibility and safety of intracardiac echocardiography (ICE)-guided Watchman FLX implantation.

METHODS

A single-center prospective registry of atrial fibrillation patients planned for LAAC with the FLX device underwent ICE-guided implantation with conscious sedation. Transesophageal echocardiography (TEE) imaging was done preprocedure (to assess LAA size and exclude thrombus) and at clinical follow-up at 6-12 weeks. Clinical outcomes were LAA closure success, complications, leak, or DRT on follow-up TEE and major safety events.

RESULTS

The study included 30 patients: age 75 ± 8 years, 53% men, CHA₂ DS₂ -VASc 4.6 ± 1.6, and HAS-BLED 3.4 ± 1.1. The primary indication was prior bleeding in 60% (72% GI bleeding). The LAA orifice width and length were 22.7 ± 3.1 and 25.7 ± 5.7 mm, respectively. Technical success was 100% (the first-choice device was used in 28 of 30). Procedure time was less than 30 min in 27 of 30 cases, with 36 ± 15 ml contrast used. The final device size was 29.2 ± 4.7 mm with 21.6 ± 4.5% compression. There were no procedure-related complications. Follow-up TEE at a median 47 days follow-up showed 100% device success with no DRT or peridevice leak ≥5 mm. Major safety events occurred in 6.6% (2/30).

CONCLUSION

The Watchman FLX device can be safely implanted with intraprocedural ICE imaging instead of TEE.

Plugs for left atrial appendage occlusion: an overview of available devices

INTRODUCTION

Approximately one-third of all ischemic strokes and the ensuing health and economic burden can be attributed to the presence of atrial fibrillation (AF). The global prevalence of AF continues to rise, thus making it by far the most common diagnosed cardiac arrhythmia. Percutaneous left atrial appendage (LAA) occlusion or obliteration has been developed to protect from the occurrence of stroke in patients with nonvalvular AF.

AREAS COVERED

We address the characteristics and techniques for implantation as well as some clinical registries and randomized trials of the various catheter-based devices for the occlusion of the LAA that are either currently available or in the clinical evaluation stage.

EXPERT OPINION

Over less than 2 decades, LAA occlusion progressed from being a concept applied in a few specialized centers to a globally recognized procedure implemented in numerous hospitals as part of daily interventional practice. The respective devices are to date safer and easier to deploy than initially. Periprocedural and postprocedural complications will continue to decrease as already evident from prospective randomized trials and registries. Although current indications focus on patients with nonvalvular AF and contraindications for oral anticoagulation, it is all but certain that the future will bring a widening in the spectrum of indications, applicability, and usage of these devices.

Indications and Outcome in Patients Undergoing Left Atrial Appendage Closure-The Austrian LAAC Registry

Background: Complete real-world data on the indications and outcomes of left atrial appendage closure (LAAC) outside of clinical trials are rare. In this study, we stratified patients undergoing LAAC by indication groups. Methods: This analysis of the national multicentre Austrian LAAC Registry comprised all patients that underwent LAAC up until 2018 at the currently active centres in Austria. The baseline characteristics, procedural details and outcomes between the following indication groups were compared: bleeding as an indication for LAAC (“bleeding” group) vs. thromboembolism despite oral anticoagulation (OAC; “thromboembolism” group) vs. an intolerance to OAC for reasons other than the above (“other” group). Results: The analysis included 186 patients, with 59.7% in the “bleeding” group, 8.1% in the “thromboembolism” group and 32.2% in the “other” group. The CHADS₂ score was the highest in the “thromboembolism” group and the HAS-BLED score was the highest in the “bleeding” group. The procedural outcomes were similar between groups (implantation success, 97.3%), with major complications occurring in 7.0% of patients. One-year survival free from stroke, bleeding or LAAC-associated hospitalisation was 83.9%, 90.0% and 81.4% in the “bleeding”, “thromboembolism” and “other” groups, respectively (p = 0.891). Conclusions: In routine clinical practice, LAAC was used in a heterogeneous patient population with atrial fibrillation (AF) and contraindication, inefficacy or intolerance to OAC. The long-term outcome was favourable in all groups.

Left atrial appendage closure with zero fluoroscopic exposure via intracardiac echocardiographic guidance

BACKGROUND/PURPOSE

Left atrial appendage closure (LAAC) is conventionally guided by fluoroscopy and transesophageal echocardiography. We introduce an LAAC technique without fluoroscopy exposure using intracardiac echocardiography (ICE) and electroanatomic mapping system (EAMS) under local anesthesia.

METHODS

Seven non-valvular atrial fibrillation patients who underwent LAAC with the LAmbre devices under the ICE and EAMS guidance were compared to 7 patients following the conventional approach by propensity score matching. ICE probe was advanced into the left atrium (LA) to guide sizing and device implantation following the orthogonal tri-axial technique (Axis-X: from left pulmonary veins [PVs] to LAA; Axis-Y: from right PV ostium to LAA; Axis-Z: from lower LA to LAA).

RESULTS

The mean diameters of ostia and landing zone were 21.4 ± 3.9 mm and 20.4 ± 4.2 mm, respectively. LAmbre devices with a mean umbrella diameter of 23.7 ± 4.2 mm and cover disc diameter of 29.4 ± 3.6 mm were successfully implanted and acute complete LAA sealing without peri-device leak (PDL) were achieved in all cases. Neither fluoroscopy exposure nor contrast consumption was recorded. No procedure related complications were documented. The mean procedural time and PDLs at follow-ups were comparable to those in the conventional group. No stroke or thromboembolic events were documented.

CONCLUSION

The fluoroscopy exposure could be minimized, even to zero, in the ICEguided LAAC procedures feasibly and safely using LAmbre devices. The orthogonal triaxial technique is considered efficacious and safe for the procedures.

4D Volume Intracardiac Echocardiography for Intraprocedural Guidance of Transcatheter Left Atrial Appendage Closure

Background

Fluoroscopy and transesophageal echocardiography (TEE) are used to guide transcatheter left atrial appendage (LAA) closure in patients with atrial fibrillation to prevent thromboembolic events. This study examines whether real-time three-dimensional volume ICE guidance (4D volume ICE) can be used as an alternative to TEE during LAA closure (LAAC).

Methods and Results

Fifteen patients with atrial fibrillation (AF), who had high risk for stroke and contraindication for long-term warfarin therapy, were enrolled in the study. The WATCHMAN device was used for transcatheter LAAC under fluoroscopy. LAA and device sizing was performed using TEE and volume ICE guidance from the right heart. Intraprocedural ICE measurements were consistent with TEE; LAA maximal width and depth, and maximal diameter of the implanted device were moderately correlated (Pearson's coefficient: 0.63, 0.65, and 0.71 respectively; p<0.05) with good agreement (bias: -0.03 cm, -0.07 cm, and 0.003 cm respectively). The average imaging success rate, defined by the number of patients with all the required intraprocedural measurements, was 67% for ICE and 100% for TEE. The WATCHMAN device was successfully implanted in all patients with a device to patient ratio of 1.33.

Conclusions

4D volume ICE can be used as an intraprocedural sizing and guidance tool for transcatheter LAAC with measurements comparable to TEE. Challenging patient characteristics significantly degrade the diagnostic image quality when imaging from the right heart. Standardized workflow with proper patient selection and optimal preprocedural planning may improve the diagnostic quality of volume ICE guidance for transcatheter LAAC procedure.