Is a transesophageal echocardiogram (TEE) required for a Watchman left atrial appendage closure device?

Is TEE Required for Watchman Device Implantation?

Yes, either transesophageal echocardiography (TEE) or intracardiac echocardiography (ICE) is required for Watchman left atrial appendage closure procedures, according to established institutional and operator requirements.

Guideline-Based Imaging Requirements

The SCAI/ACC/HRS consensus guidelines explicitly mandate that imaging for LAA occlusion procedures must include 1:

• Fluoroscopy (ideally biplane)
• Either TEE or ICE (not optional—one must be used)
• Hemodynamic monitoring system

The guidelines state that "optimal imaging of the LAA itself typically requires TEE or ICE guidance" for proper device sizing, positioning, and assessment of adequate closure 1.

TEE vs ICE: The Current Evidence

While both modalities are acceptable, there are important distinctions:

TEE Remains the Gold Standard

• All pivotal trials (PROTECT AF, PREVAIL) establishing Watchman safety and efficacy used TEE guidance 2
• TEE provides comprehensive LAA visualization in multiple planes necessary for precise transseptal puncture placement 1
• The most recent European consensus (2025) advises that "guidance with TOE or ICE is advised for transcatheter LAA occlusion" 3

ICE as an Alternative

Recent data shows ICE is increasingly adopted but with caveats:

• Higher procedural success (marginally): OR 1.33 in 2025 meta-analysis 4
• Increased complications: Significantly higher pericardial effusion rates (OR 2.11) and residual atrial septal defects (OR 1.52) 4
• Learning curve matters: In the SURPASS registry, pericardial effusion requiring intervention was significantly higher with ICE (1.0% vs 0.5%, p=0.02), particularly when operators had performed <10 ICE-guided procedures 2
• ICE avoids general anesthesia and esophageal injury risk 5

Fluoroscopy-Only Approaches: Not Recommended

While pilot studies have explored fluoroscopy-only guidance 6, 7, this approach:

• Contradicts established guidelines 1
• Uses higher radiation doses and contrast volumes 6
• Lacks systematic validation for safety
• Should be considered investigational only

Clinical Algorithm

For standard Watchman implantation:

1. Pre-procedure: TEE to assess LAA anatomy, exclude thrombus, and plan device size
2. Intra-procedure: Either TEE (with general anesthesia) or ICE (with conscious sedation)
   • Choose TEE if: Complex anatomy, operator inexperienced with ICE, or institutional standard
   • Choose ICE if: Patient cannot tolerate TEE/general anesthesia AND operator experienced with ICE (>10 cases)
3. Post-procedure: TEE at 45-90 days to assess device position, peridevice leak, and device-related thrombus 3

Critical Pitfalls

• Never attempt Watchman without either TEE or ICE—this violates consensus guidelines and increases perforation risk
• ICE requires specific training; the higher complication rates reflect operator learning curves 2
• The LAA is a multilobar, thin-walled structure prone to perforation—real-time imaging is essential for safety 1
• Intraprocedural embolic events were significant during early PROTECT AF experience, emphasizing the need for meticulous imaging guidance 1