Comparative Outcomes of Intracardiac vs Transesophageal Echocardiographic Guidance for Left Atrial Appendage Occlusion: Insights From EMERGE LAA Postapproval Study

Abstract

Background: Transesophageal echocardiography (TEE) is commonly used to guide left atrial appendage occlusion (LAAO) procedures. Intracardiac echocardiography (ICE) is emerging as an alternative imaging modality with potential advantages over TEE.

Objectives: The aim of this study was to compare outcomes from procedures guided by ICE vs TEE vs both for guidance of Amulet implantation in the EMERGE LAA postapproval study.

Methods: Patients with Amulet implants entered into the National Cardiovascular Data Registry LAAO Registry between August 14, 2021, and December 15, 2023. A safety composite endpoint of all-cause death, ischemic stroke, systemic embolism, or device- or procedure-related events requiring open cardiac surgery or major endovascular intervention through 7 days or hospital discharge was reported. Major adverse events were also reported through 45 days.

Results: A total of 11,848 patients were included in this analysis, with 433 (3.7%) using ICE only, 9,793 (82.6%) TEE only, and 1,622 (13.7%) ICE plus TEE. Median follow-up duration was the same in all groups (45.0 days; Q1-Q3: 45.0-45.0 days). Baseline characteristics were comparable across all groups. Similar rates of implantation success (ICE, 95.0%; TEE, 96.1%; ICE plus TEE, 96.2%; P = 0.324) and clinically relevant closure (≤3-mm peridevice leak) at 45 days (>95% for all groups) were observed. Procedural times were longer in the ICE (104.8 ± 44.7 minutes; median 98.0 minutes; Q1-Q3: 78.0-122.0 minutes) and ICE plus TEE (98.8 ± 46.6 minutes; median 88.5 minutes; Q1-Q3: 71.0-116.0 minutes) groups compared with the TEE group (82.0 ± 39.2 minutes; median 75.0 minutes; Q1-Q3: 57.0-99.0 minutes) (P < 0.001). The safety composite endpoint (ICE, 0.9% [4 of 433]; TEE, 0.9% [93 of 9,793]; ICE plus TEE, 0.7% [11 of 1,622]; OR for ICE vs TEE: 0.97 [95% CI: 0.36-2.66]; OR for ICE vs ICE plus TEE: 1.37 [95% CI: 0.43-4.31]; P = 0.585) and 45-day major adverse event composite (ICE, 7.1% [30 of 433]; TEE, 6.7% [651 of 9,793]; ICE plus TEE, 5.7% [93 of 1,622]; OR for ICE vs TEE: 1.08 [95% CI: 0.75-1.57]; OR for ICE vs ICE plus TEE: 1.27 [95% CI: 0.83-1.93]; P = 0.336) were similar between imaging groups. Procedural times and adverse event rates decreased as operator experience increased in the ICE groups.

Conclusions: In the largest comparison to date, both ICE and TEE are safe and effective for Amulet LAAO guidance, with high acute success and closure rates. ICE was associated with longer procedure times that decreased with operator experience, potentially reflecting a learning curve.

Keywords: Amulet; LAAO Registry; atrial fibrillation; intracardiac echocardiography; left atrial appendage; transesophageal echocardiography.