Routine concomitant closure of the left atrial appendage (LAA) during open-heart surgery should not be considered unless patients are high risk for stroke, results of the LAACS-2 trial, presented at the European Society of Cardiology (ESC) congress (28–31 August, Munich, Germany), have shown.
Surgical closure of the LAA is recommended in ESC guidelines as an adjunct to oral anticoagulation for patients with atrial fibrillation (AF) undergoing cardiac surgery. However, evidence is lacking in patients without a known history of AF.
Helena Dominguez (Bispebjerg University Hospital, Copenhagen, Denmark) and colleagues previously conducted the LAACS trial in patients undergoing open-heart surgery.
“With long-term follow-up, we observed lower risk of stroke after LAA closure, whether the patient had AF or not,” she noted. “We conducted the much larger LAACS-2 trial to further investigate if LAA closure has a protective effect in patients with, but mostly without, prior AF.”
The LAACS-2 trial was carried out across four sites in Denmark, Spain and Sweden. Patients undergoing first-time planned open-heart surgery without AF and those with a previous diagnosis of paroxysmal or chronic AF were included. A total of 1,500 patients were randomised 1:1 to either concomitant LAA closure or standard care via open LAA. The mean age was 67 years and 18.5% were female. Before surgery, 4.1% had AF, 6.1% had prior stroke and 2.5% had prior transient ischaemic attack.
Across a median of four years’ follow-up, there was no significant difference in the primary outcome of stroke or transient ischaemic attack with LAA closure versus standard care (4.28% vs 5.04%, respectively; hazard ratio, 0.85; 95% confidence interval, 0.53 to 1.37; p=0.517).
Of note, patients who had the highest stroke risk at baseline—CHA2DS2-VASc score above the median—had a 56% reduction in the primary endpoint with LAA closure (p=0.018), while no significant benefit was observed in those with lower stroke risk.
Overall, there was no significant difference in mortality between the groups.
“Our results do not support routine LAA closure in all patients undergoing planned cardiac surgery. However, closure appeared to confer protection in patients at high risk of stroke,” concluded Dominguez. “As we saw in the LAACS trial, the primary endpoint curves diverged over time in LAACS-2 and follow-up will be continued.”
Dominguez also highlighted an ongoing mechanistic study that aims to further understand stroke risk following LAA closure in patients undergoing open-heart surgery.
