Study title: OPINION trial – 1-year results: Effect of left atrial appendage occlusion during valvular surgery in patients without atrial fibrillation

Congress: ESC 2025

Link: https://www.escardio.org/The-ESC/Press-Office/Press-releases/Lack-of-benefit-from-left-atrial-appendage-occlusion-for-some-patients-after-valvular-surgery

Prepared by: Dr. Murat Karaçam

Introduction
The left atrial appendage (LAA) is the most common site of thrombus formation in patients with atrial fibrillation (AF). Surgical LAA occlusion (SLAAO) has been shown to reduce stroke risk in patients with AF. However, in patients without AF but at high risk of thromboembolism undergoing valve surgery, the benefit of SLAAO remains uncertain.

Objective
The OPINION trial was designed to evaluate whether routine SLAAO reduces ischemic stroke, transient ischemic attack (TIA), and cardiovascular mortality in valvular surgery patients without AF but with high thromboembolic risk.

Methods
The trial was conducted at three centers in China.

• Inclusion criteria: Age >18 years, no history of AF, CHA²DS²-VASc ≥2, indication for mitral or aortic valve surgery.
• Participants were randomized (1:1) to undergo routine SLAAO or no SLAAO at the time of valve surgery.
• Intraoperative transesophageal echocardiography (TEE) was used to confirm LAA closure success.
• Primary endpoint: Composite of ischemic stroke, TIA, or cardiovascular mortality at 1 year.

Results
A total of 2,118 patients were enrolled (mean age 56 years; 33% women; mean CHA²DS²-VASc 2.9).

• Primary endpoint:
• SLAAO group: 6.9%
• Control group: 8.2%
• HR 0.83; 95% CI 0.61–1.14; p=0.25
• No significant differences were observed in secondary outcomes (individual components of the primary endpoint and bleeding events).
• Prespecified subgroup analyses generally showed consistent results; however, there was a modest trend toward benefit in patients with CHA²DS²-VASc ≥3 (HR 0.81; 95% CI 0.56–1.17).

Conclusion
The OPINION trial demonstrated that in patients without AF undergoing valve surgery, routine SLAAO did not reduce ischemic stroke, TIA, or cardiovascular mortality during 1-year follow-up.

Commentary
This study shows that routine SLAAO provides no meaningful improvement in clinical outcomes in patients without AF. The investigators plan further analyses and longer follow-up (3 years) to clarify whether potential benefits may emerge in high-risk subgroups (e.g., CHA²DS²-VASc ≥3). Additionally, in this patient population, anticoagulation strategies beyond SLAAO may play an important role in reducing stroke risk.