No clear benefit from surgical left atrial appendage occlusion in non-AF patients after valve surgery

No benefit in terms of prevention of ischemic stroke, transient ischemic attack and cardiovascular mortality after 1 year was observed when surgical left atrial appendage occlusion was performed in high-risk non-atrial fibrillation patients after valvular surgery, according to late-breaking research presented in a Hot Line session today at ESC Congress 2025.

Surgical left atrial appendage occlusion (SLAAO) is a procedure designed to block the left atrial appendage, which is a common site for clot formation.

While SLAAO reduces stroke in atrial fibrillation (AF) patients, its efficacy in high-risk non-AF patients remains uncertain. We conducted the OPINION trial to address this important clinical question - does SLAAO reduce thromboembolic events in non-AF patients at high risk of stroke after valvular surgery?"

Professor Yang Wang, trial presenter, from the State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Beijing, China

OPINION was an open-label, randomised, superiority trial conducted at three cardiac surgery centres in China. Eligibility criteria included age >18 years, no AF diagnosis, CHA₂DS₂VASc ≥2 and an indication for valvuloplasty or replacement due to mitral or aortic valve lesions. Participants were randomised 1:1 to standard surgical care with concomitant SLAAO or without SLAAO. Intraoperative transoesophageal echocardiography was mandatory to assess the SLAAO, with immediate surgical revision required if the residual appendage stump exceeded 1 cm after the initial closure attempt. The primary endpoint was a composite of ischaemic stroke, transient ischaemic attack (TIA) or cardiovascular mortality assessed at 1 year using the intention-to-treat (ITT) principle.

The ITT population included 2,118 patients who had a mean age of 56 years and 33% were female. The mean CHA₂DS₂VASc score was 2.9.

The primary endpoint of ischaemic stroke, TIA or cardiovascular mortality was not significantly different between the groups, occurring in 6.9% of patients in the SLAAO group and 8.2% of patients in the control group (hazard ratio [HR] 0.83; 95% confidence interval [CI] 0.61 to 1.14; p=0.25).

There was no significant difference in secondary endpoints, including components of the primary endpoint and bleeding events. Prespecified subgroup analyses were generally consistent, although there was a suggestion of benefit with SLAAO in high-risk patients with CHA₂DS₂VASc ≥3 (HR 0.81; 95% CI 0.56 to 1.17).

Summarizing the results, first author, Doctor Xin Yuan, also from the State Key Laboratory of Cardiovascular Disease, said: "The trial found no significant benefit of routine SLAAO in the overall study population. Our results may help avoid unnecessary procedures and guide future research. We have planned further analyses of SLAAO in high-risk subgroups and, given the divergence in primary endpoint event curves observed after 6 months, we are extending follow-up to 3 years. Beyond SLAAO, optimisation of stroke prevention in high-risk patients after valvular surgery may lie in other strategies, including anticoagulation."