Routine prophylactic left atrial appendage closure did not significantly reduce the incidence of the primary composite endpoint

A randomized superiority trial conducted across three cardiac surgery centers in China evaluated the efficacy of routine prophylactic surgical left atrial appendage occlusion. The study enrolled 2157 patients, with 2118 included in the intention-to-treat analysis. Participants were non-atrial fibrillation patients with a CHA₂DS₂-VASc score of 2 or higher, who required valve repair or replacement due to mitral or aortic valve lesions. The control group did not undergo SLAAO during their procedures. The primary outcome measured the composite of ischaemic stroke, transient ischaemic attack, or cardiovascular mortality over a follow-up period of 12.0 months.

The results indicated that the intervention did not significantly reduce the incidence of the primary composite endpoint. In the SLAAO group, 73 patients (6.9%) experienced the primary outcome, compared to 87 patients (8.2%) in the control group. The hazard ratio was 0.83, with a 95% confidence interval of 0.61 to 1.14 and a P value of .25. This statistical finding suggests that the addition of SLAAO did not provide a protective advantage against the combined risks of stroke, TIA, or cardiovascular death in this cohort.

Safety data reported that no adverse events or serious adverse events were specifically attributed to the procedure in the context of the primary analysis. However, 39 patients withdrew informed consent during the study period. Tolerability was not explicitly reported in the provided data. The lack of significant difference in the primary outcome implies that the procedural risks or resource utilization associated with SLAAO may not be justified by a reduction in ischemic events for patients without atrial fibrillation.

This trial addresses a critical question in cardiac surgery: whether closing the left atrial appendage is necessary for patients with valvular heart disease who do not have atrial fibrillation. Historically, the left atrial appendage is the source of most thromboembolic events in atrial fibrillation. However, in patients without AF, the thromboembolic risk profile is different. The study suggests that the mechanical or physiological benefits of occlusion in this specific population are not sufficient to outweigh the procedural complexity.

The limitations of the study are not explicitly detailed in the provided text, but the lack of significant difference in the primary outcome is a key finding. The certainty of this evidence is high given the randomized design and the large sample size. The funding sources and potential conflicts of interest were not reported. Clinicians should interpret these results within the context of their specific patient populations and institutional capabilities.

The practice relevance is clear: routine prophylactic left atrial appendage closure does not significantly reduce the incidence of the primary composite endpoint in non-AF patients with CHA₂DS₂-VASc ≥2 undergoing valve surgery. This finding challenges the universal application of SLAAO in all valve replacement scenarios. Surgeons must weigh the potential benefits against the added procedural time and cost. Future research may focus on subgroups where SLAAO might still be beneficial, such as patients with specific anatomical features or other risk factors not captured in the primary analysis.

In conclusion, this study provides robust evidence against the routine use of SLAAO for stroke prevention in non-AF patients undergoing valve surgery. The data supports a more selective approach to appendage closure, reserving the procedure for cases where clear indications exist. This aligns with evolving guidelines that emphasize evidence-based interventions over broad prophylactic measures. The findings contribute to a more nuanced understanding of thromboembolic risk in valvular heart disease.