LAACS-2Cardiac SurgeryOpen Access
Left Atrial Appendage Closure During Open-Heart Surgery for Stroke Prevention
Left atrial appendage closure concomitant with cardiac surgery
Why the trial?
Surgical closure of the left atrial appendage during cardiac surgery may prevent later stroke, but evidence outside patients with known atrial fibrillation is limited. LAACS-2 tested routine concomitant appendage closure at the time of cardiac surgery.
Does concomitant left atrial appendage closure reduce stroke or TIA in patients undergoing first-time planned open-heart surgery?
Population
1,500 first-time planned open-heart surgery patients; mean age 67, 4.1% with AF
Comparison
Concomitant surgical LAA closure vs standard care (appendage left open)
Design
Multicenter 1:1 randomized trial (4 sites: Denmark, Spain, Sweden)
Follow-up
Median 4.0 years
Key result
Concomitant left atrial appendage closure did not significantly reduce stroke or TIA compared to standard care (4.28% vs 5.04%; HR 0.85; 95% CI 0.53-1.37; p=0.517).
Authors
Discussion
Member takes
Where experts stand
LAACS-2 tested whether surgical left atrial appendage closure should be added routinely to planned open-heart surgery, including in patients without prior atrial fibrillation. Over a median 4.0 years it did not significantly reduce stroke or TIA versus standard care (4.28% vs 5.04%; HR 0.85, 95% CI 0.53-1.37; p=0.517). Expert reaction to the earlier LAACS data had been divided; the new readout leaves routine closure unsupported overall, with a signal in patients whose CHA2DS2-VASc was above the median.
Main debate
Split on whether LAACS data support routine appendage closure
Supports routine closure1
The study results make it advisable to routinely add surgical closure of the left atrial appendage to planned open heart surgery.vs
Signal still unclear2
There is not a clear signal one way or the other, and it would also be reasonable not to perform appendage occlusion.Not placed2 reporting, watching, or context only
1 take classified by contention axis so far — the map appears as more land.
Still unclear
Whether the high-CHA2DS2-VASc subgroup signal will hold in LeAAPS and LAA-CLOSURE, and whether longer LAACS-2 follow-up changes the overall null, remains open.
Key expert perspectives
Left atrial appendage occlusion is reasonable but so is not performing it
For surgeons, left atrial appendage occlusion is a reasonable thing to do for patients at high risk of developing atrial fibrillation, but there is not a clear signal one way or the other. It would also be reasonable not to perform it.
Distilled from their postOriginal post
VFVolkmar FalkCardiothoracic surgery director, Charité Medical University BerlinEndpoint critiqueAug 28
LAACS addresses an important question but does not provide the answer
Despite tackling an important clinical question, the LAACS study does not deliver a definitive answer on routine surgical appendage closure.
Distilled from their postOriginal post
Routine surgical closure of the left atrial appendage in open heart surgery is advisable
Based on the study findings, it would be advisable to routinely add surgical closure of the left atrial appendage to planned open heart surgery.
Distilled from their postOriginal post
Overview
Does not reduce stroke or TIA with routine LAA closure; challenges broad adoption and leaves high CHA2DS2-VASc benefit for targeted trials.
Key Points
- To evaluate whether concomitant left atrial appendage closure reduces the incidence of stroke or transient ischemic attack in patients undergoing planned open-heart surgery.
- Multicenter randomized trial (LAACS-2) conducted across four sites in Denmark, Spain, and Sweden enrolling 1,500 patients undergoing first-time planned open-heart surgery.
- Participants were randomly assigned 1:1 to concomitant left atrial appendage closure or standard care (open left atrial appendage) and followed for a median of 4.0 years.
- Stroke or transient ischemic attack occurred in 4.28% of the closure group versus 5.04% of the standard care group (HR 0.85, 95% CI 0.53 to 1.37; p=0.517).
- Patients with a baseline CHA2DS2-VASc score above the median experienced a 56% reduction in the primary endpoint (p=0.018), whereas lower-risk patients showed no significant difference.
- Overall mortality did not differ between the intervention and standard care arms.
Evidence details
What drove the result?
| Outcome | LAA closure | Open LAA |
|---|---|---|
| Stroke or TIA | 4.28% | 5.04% |
| Primary endpoint · HR 0.85 (95% CI 0.53-1.37); p=0.517 | ||
| Stroke or TIA, CHA2DS2-VASc above median | ||
| Subgroup · 56% relative reduction (p=0.018); per-arm rates not reported; no benefit at lower stroke risk | ||
Limitations & tradeoffs
Representation
Only 4.1% of patients had atrial fibrillation at baseline, so the result mainly addresses patients without an anticoagulation indication.
Subgroup caution
The CHA2DS2-VASc subgroup benefit is hypothesis-generating; per-arm subgroup rates are not reported.
Statistical certainty
The wide CI (0.53–1.37) leaves room for a meaningful overall benefit.
Design limitations
No surgical safety or complication data are reported in the record.
Structured PICO
Does concomitant left atrial appendage closure reduce stroke or TIA in patients undergoing first-time planned open-heart surgery?
P
Population
1,500 patients undergoing first-time planned open-heart surgery, followed for a median of 4.0 years.
I
Intervention
Concomitant left atrial appendage closure during open-heart surgery
C
Comparator
Standard care (open LAA) during open-heart surgery
O
Outcome
Stroke or TIA at median 4.0 yearshard clinical
Routine concomitant left atrial appendage closure during first-time open-heart surgery did not significantly reduce the overall risk of stroke or TIA, though a benefit was observed in patients with higher baseline CHA2DS2-VASc scores.
Main Result
Hazard Ratio: 0.85 (95% CI 0.53–1.37)
Absolute Event Rate: 4.28% vs 5.04%
p-value: p=0.517
Cite This Study
Helena Dominguez (2026) conducted an RCT in first-time planned open-heart surgery (n=1,500). Concomitant left atrial appendage closure vs. Standard care (open LAA) was evaluated on stroke or TIA (HR 0.85, 95% CI 0.53-1.37, p=0.517). Concomitant left atrial appendage closure did not significantly reduce stroke or TIA compared to standard care (4.28% vs 5.04%; HR 0.85; 95% CI 0.53-1.37; p=0.517).