TEE After LAA Clip Placement During Surgery
Yes, transesophageal echocardiography (TEE) is strongly recommended immediately after LAA clip placement during surgery to verify successful closure, and success is defined as complete absence of flow into the LAA with no residual stump >1.0 cm. 1
Why TEE is Essential
The evidence is clear that surgical LAA closure frequently fails—approximately 50-60% of closures are incomplete when assessed by echocardiography 1. The critical issue is that incomplete closure creates a thrombogenic environment with stagnant blood flow, leading to thrombus formation in 25-41% of unsuccessful closures 1, 2, 3. This directly impacts stroke risk, which is the entire reason for performing the procedure.
For LAA clips specifically (such as the FDA-approved Gillinov-Cosgrove clip system), recent high-quality evidence shows a 98.4% success rate when assessed by TEE 4, making them superior to other techniques. However, this success rate depends on intraoperative verification and correction when needed.
How to Check Success Intraoperatively
Perform TEE immediately after clip deployment using these specific criteria:
Technical Approach 5, 2
- Use mid-esophageal views at 45-135° with counterclockwise rotation and gentle anteflexion
- Sweep through multiple angles (0-135°) to visualize the entire LAA
- If available, use 3D TEE for en face visualization of the LAA orifice 6
Assessment Protocol
- Color Doppler interrogation: Sweep through all views looking for ANY flow between the left atrium and LAA 1, 2
- Measure residual stump: Any remnant LAA tissue must be <1.0 cm in maximum length 1
- Check for thrombus: Examine for any pre-existing or acute thrombus formation 1
Definition of Success
Success requires BOTH criteria to be met 1:
- No flow: Complete absence of color Doppler flow from the left atrial body into the LAA
- No significant stump: Residual LAA tissue ≤1.0 cm in maximum length
Any persistent flow or stump >1.0 cm = failure and requires immediate reintervention during the same operation 7.
Critical Pitfalls to Avoid
Do not assume the clip is properly positioned without TEE confirmation. Studies show that when surgeons believe closure is complete without imaging verification, failure rates are 40-60% 1, 2, 7. One prospective study found that 60% of stapled excisions and 13% of internal ligations had early failures that were only detected and corrected because of intraoperative TEE 7.
If incomplete closure is detected intraoperatively, reintervene immediately 7. Late follow-up studies show that gaps can develop over time (57% in one series), but many failures are present from the initial procedure and simply go undetected without imaging 7, 3.
Anticoagulation Implications
This is why TEE matters for patient outcomes: Incomplete LAA closure is strongly associated with thromboembolic events 1. The 2014 AHA/ACC/HRS guidelines explicitly state that thrombus identification in ~25% of unsuccessful closures "constitutes important data guiding the continued need for anticoagulation in patients who have undergone surgical LAA ligation" 1.
If closure is unsuccessful and cannot be corrected intraoperatively, the patient must remain on anticoagulation indefinitely 1. This defeats the purpose of the procedure for patients undergoing LAA closure specifically to avoid anticoagulation.
Follow-up Imaging
While intraoperative TEE is essential, consider repeat TEE at 3-6 months to assess for late dehiscence or gap formation, particularly if anticoagulation cessation is planned 4, 7. However, the LAA clip technique has shown excellent durability with minimal late failures compared to suture or stapler techniques 4.