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.

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.

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.

CT-Based Preplanning Allows Abstaining from Intraprocedural TEE during Interventional Closure of the LAA in Patients with Atrial Fibrillation

OBJECTIVES

The aim of this study was to determine whether the application of a CT-based preplanning algorithm might allow abstaining from TEE during LAAC.

BACKGROUND

LAAC is an established treatment alternative for patients with atrial fibrillation. Today, most LAAC procedures are guided by TEE, which, however, leads to the need for patient sedation and might even cause direct harm to the patient. CT-based preplanning of the LAAC procedure, in combination with technical improvements in device design and interventional experience, might allow abstaining from TEE.

METHODS

Fluoro-FLX is a prospective single-center study to evaluate how often TEE leads to a procedural change during interventional LAAC if a dedicated CT planning algorithm is applied. The study hypothesis is that under these circumstances, a sole fluoroscopy-guided LAAC is an alternative to a TEE-guided approach. All procedures are preplanned by cardiac CT and, finally, guided by fluoroscopy only, while TEE is carried out in the background during the intervention for safety reasons.

RESULTS

In none of the 31 consecutive patients did TEE lead to a change in the preplanned fluoroscopy-guided LAAC (success ratio: 1.00; CI: 0.94-1.00), thereby meeting the primary endpoint (performance goal: 0.90). There were no procedure-related adverse cardiac or cerebrovascular events (no pericardial effusion, TIA, stroke, systemic embolism, device embolism, death).

CONCLUSIONS

Our data suggest that it is feasible to perform LAAC under sole fluoroscopic guidance if preplanning is performed using cardiac CT. This might be worth considering, especially in patients who are at high risk for TEE-related adverse events.

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.

Atrial Fibrillation Ablation: Impact of Intracardiac Echocardiography in Reducing Procedure Time and Hospitalization

BACKGROUND

Intracardiac echocardiography (ICE) allows visualization of cardiac structures and recognition of complications during atrial fibrillation ablation (AFA). Compared to transesophageal echocardiography (TEE), ICE is less sensitive to detecting thrombus in the atrial appendage but requires minimal sedation and fewer operators, making it attractive in a resource-constrained setting.

OBJECTIVE

To compare 13 cases of AFA using ICE (AFA-ICE group) with 36 cases of AFA using TEE (AFA-TEE group).

METHODS

This is a single-center prospective cohort study. The main outcome was procedure time. Secondary outcomes: fluoroscopy time, radiation dose (mGy/cm2), major complications, and length of hospital stay in hours. The clinical profile was compared using the CHA2DS2-VASc score. A p-value <0.05 was considered a statistically significant difference between groups.

RESULTS

The median CHA2DS2-VASc score was 1 (0-3) in the AFA-ICE group and 1 (0-4) in the AFA-TEE group. The total procedure time was 129 ± 27 min in the AFA-ICE group and 189 ± 41 min in the AFA-TEE group (p<0.001); the AFA-ICE group received a lower dose of radiation (mGy/cm2, 51296 ± 24790 vs. 75874 ± 24293; p=0.002), despite the similar fluoroscopy time (27.48 ± 9. 79 vs. 26.4 ± 9.32; p=0.671). The median length of hospital stay did not differ; 48 (36-72) hours (AFA-ICE) and 48 (48-66) hours (AFA-TEE) (p=0.27).

CONCLUSIONS

In this cohort, AFA-ICE was related to shorter procedure times and less exposure to radiation without increasing the risk of complications or the length of hospital stay.

A Randomized Trial of Preoperative Planning of Left Atrial Appendage Occlusion Using Cardiac Computed Tomography Angiography

Objective. To evaluate the value of individualized planning of left atrial appendage occlusion (LAAO) using cardiac computed tomography angiography (CCTA) reconstruction techniques. Methods. A total of 96 patients treated for LAAO with the Watchman occluder were included in this study. All patients were randomized by random number table in a 2:1 ratio into the CCTA (+) and CCTA (-) groups according to whether CCTA was performed preoperatively. 3D cardiac reconstruction was performed preoperatively in the CCTA (+) group to plan the location of the atrial septal puncture site, left atrial appendage(LAA) landing zone, predict the size of the occluder and simulate occluder release. In the CCTA(-) group, only transesophageal echocardiography (TEE) and fluoroscopy were used to guide LAAO. Results. The number of occluders used in a single procedure (1.06 ± .24 vs 1.22 ± .42), the number of intraoperative angiography positions (1.23 ± .58 vs 2.28 ± .85) and the procedure time (45.88 ± 5.08 vs 62.44 ± 5.60) in the CCTA(+) group were lower than in the CCTA(-) group (P < .05), and the first-attempt blocking success rate was higher than that of the CCTA(-) group (85.9% vs 65.6%, P = .021). Furthermore, the Bland-Altman plots showed good agreement between the longest diameter of the CCTA-predicted landing zone and the longest diameter of the actual landing zone (95% LoA -7.49, 10.24). A strong positive correlation was observed between the predicted compression ratio and the actual compression ratio (r = .890, P < .001). In addition, a strong positive correlation was found between the CCTA-predicted longest diameter of the landing zone and the actual occluder size (r = .863, P < .001). Conclusion. Accurate planning for LAAO using preoperative CCTA can reduce intraoperative angiography positions and occluder changes, shorten the procedure time, increase the success rate of first-attempt blocking and reduce the difficulty of the procedure.

Intracardiac echocardiography Chinese expert consensus

In recent years, percutaneous catheter interventions have continuously evolved, becoming an essential strategy for interventional diagnosis and treatment of many structural heart diseases and arrhythmias. Along with the increasing complexity of cardiac interventions comes ever more complex demands for intraoperative imaging. Intracardiac echocardiography (ICE) is well-suited for these requirements with real-time imaging, real-time monitoring for intraoperative complications, and a well-tolerated procedure. As a result, ICE is increasingly used many types of cardiac interventions. Given the lack of relevant guidelines at home and abroad and to promote and standardize the clinical applications of ICE, the members of this panel extensively evaluated relevant research findings, and they developed this consensus document after discussions and correlation with front-line clinical work experience, aiming to provide guidance for clinicians and to further improve interventional cardiovascular diagnosis and treatment procedures.

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.

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.

Impact of ultrasound contrast agent during transoesophageal echocardiography on the sizing of the left atrial appendage

INTRODUCTION

Interventional closure of the left atrial appendage closure (LAAC) has been established as an alternative treatment in patients with atrial fibrillation (AF) and an increased risk of stroke. So far it is unknown whether the use of ultrasound contrast agent (UCA) would influence the correct sizing of the LAA and thereby have an impact on device selection during interventional LAAC.

METHODS

Between January 2017 and April 2018, 223 transoesophageal echocardiography (TOE) examinations were prospectively performed in adult patients with non-valvular AF (Impact of the use of ultrasound contrast agent on the detection of thrombi in the left atrial appendage during transesophageal echocardiography (CONDOR) study). LAA was examined both with and without the use of UCA. The following measurements were taken at 0^o, 45^o, 90^o and 135^o: diameter of LAA ostium, maximal depth of the LAA, maximal available depth of the LAA orthogonal to the ostial plane and area of the LAA.

RESULTS

The use of UCA had no relevant influence on the size determination of the LAA. Additionally, Bland-Altman blots demonstrate a high degree of correlation between the measurements with and without UCA with no evidence for a systematic effect arising from the use of UCA. When comparing the measurements of two independent investigators, the use of UCA rather leads to a higher variability than to an improved precision.

DISCUSSION

Despite the fact that the use of UCA during TOE leads to an improved rule out of thrombi, our study shows that there is no advantageous effect of UCA on the size determination of the LAA and should therefore not be used for this purpose.

Iatrogenic atrial septal defect after percutaneous left atrial appendage closure: a single-center study

There is conflicting evidence regarding the significance of iatrogenic atrial septal defects (iASDs) after transseptal puncture during percutaneous cardiac interventions. To study the clinical outcome of iASD after percutaneous left atrial appendage occlusion (LAAo). Single-center, retrospective study of 70 consecutive patients who underwent percutaneous LAAo between May 2010 and August 2017, and subsequent transesophageal echocardiography (TEE) at 1 month. The sample population was divided into two groups: A (with iASD, 22 (37%) patients) and B (no iASD, 44 (63%) patients). Procedures were guided either by TEE (36 patients (54%)) or intracardiac echocardiography (ICE) from the left atrium (30 patients (46%)). The primary end point was presence of iASD at 1 month, and secondary end points included mortality, hospital admission due to heart failure (HF), and right atrium (RA) size during follow-up. 70 patients were included in this study and the prevalence of iASD at 1 month was 37%. The use of ICE was associated with iASD (adjusted odds ratio, 3.79; 95% CI 1.27-11.34). The presence of iASD was not associated with adverse events (mortality, 15.4% vs 20.5%; P = 0.60; HF hospitalizations, 7.7% vs 13.6%, P = 0.45; and RA area, 24.8 ± 7.0 cm² vs 22.2 ± 6.8 cm², P = 0.192). At 1-month follow-up after LAAo, iASD was present in one third of patients, but was not associated with clinical outcomes. The use of ICE was associated with a higher risk of short-term iASD.

Left atrial appendage occlusion in COVID-19 times

The coronavirus disease 2019 pandemic is having a major impact on healthcare systems worldwide. Several months after the COVID-19 outbreak, waiting lists of non-urgent structural heart (SH) interventions continue to increase. Limitations in terms of ICU beds and anesthesiology represent a major limitation to conduct non-urgent SH interventions and are a valid reason to move towards less invasive approaches. The field of left atrial appendage occlusion (LAAO) reflects this challenging situation perfectly. The aim of this paper is to describe the possibilities for pre-procedural LAA assessment, performance of the LAAO procedure and post-procedural surveillance in these challenging times.

Fusion Imaging of X-ray and Transesophageal Echocardiography Improves the Procedure of Left Atrial Appendage Closure

BACKGROUND

Left atrial appendage closure (LAAC) is an alternative treatment strategy for patients with atrial fibrillation who are at risk for thromboembolic events and considered not suitable for oral anticoagulation (OAC). LAAC is mainly performed under the guidance of transesophageal echocardiography (TEE) and fluoroscopy. The study presented here should analyze whether fusion imaging (FI) of transesophageal echocardiography and X-ray performed during LAAC is feasible and can improve the results of the procedure.

METHODS

The data presented here are from a retrospective single center study. Sample size was defined as 50 patients in which LAAC was performed without fusion imaging (control group) and 25 patients were the LAAC procedure was guided by fusion imaging (treatment group). Inclusion criteria were defined as age > 18 years and completion of an LAAC procedure defined as deployment of a WATCHMAN 2.5 LAA occluder. Study endpoints were procedure time, amount of used contrast medium, radiation dose, final position of the WATCHMAN in TEE (deviation from ideal positioning), and clinical endpoints, respectively.

RESULTS

LAA closure was successfully performed in all patients. No case of device embolism was occurring, and none of the patients experienced a periprocedural stroke/TIA nor a systemic embolism, respectively. Mean procedure time was 15 min shorter in the group of patients where fusion imaging was applied (p < 0.001). Additionally, the use of fusion imaging was associated with a significant reduction of contrast medium (20.6 ml less than in control; p < 0.045). Regarding the final position of the WATCHMAN, no relevant differences were found between the groups. The use of fusion imaging significantly reduced procedure time and the amount of contrast medium in patients undergoing LAAC.