# APBA Kısa Özet

Prophylactic left atrial appendage closure during bioprosthetic surgical aortic valve replacement was found to be safe and did not increase 30-day bleeding. The primary composite endpoint of cardiovascular death, stroke, or systemic embolism occurred in 2.2% of the closure group versus 3.1% of controls, but this difference was not statistically significant. A time-dependent treatment effect was observed, with hazard ratios changing direction at approximately 7 days, though neither early nor late hazards were statistically significant.

# Çalışma neyi araştırdı?

The LAA-CLOSURE trial investigated the safety and efficacy of prophylactic left atrial appendage (LAA) closure during bioprosthetic surgical aortic valve replacement in patients without prior atrial fibrillation. The study aimed to determine whether routine LAA closure could reduce thromboembolic risk in this low-risk population while assessing short-term safety outcomes.

# Yöntem

This investigator-initiated, academic, randomized, open-label, multicenter trial randomized 921 patients without prior AF undergoing bioprosthetic surgical aortic valve replacement with or without concomitant surgery. A modified intention-to-treat analysis included 904 patients (434 in the LAA closure group and 452 in the control group). The primary composite endpoint was cardiovascular death, stroke, or systemic embolism at 30 days. Secondary outcomes included postoperative atrial fibrillation, bleeding events, and safety profiles. Follow-up was limited to 30 days post-operatively.

# Temel bulgular

  • The primary composite endpoint occurred in 10 of 434 (2.2%) patients in the LAA closure group and 14 of 452 (3.1%) patients in the control group.
  • Postoperative atrial fibrillation occurred in 205 of 445 (46.1%) versus 184 of 459 (40.1%) patients (relative risk, 1.1 [95% CI, 0.99-1.3]; P =0.07).
  • The treatment effect changed direction at approximately 7 days: hazard ratios were 2.4 (95% CI, 0.62-9.4; P =0.20) between 0 and 7 days and 0.29 (95% CI, 0.080-1.0; P =0.056) between 7 and 30 days.
  • Bleeding events were comparable between groups, and prophylactic LAA closure did not increase 30-day bleeding risk.

# Bulgular ne anlama geliyor?

Prophylactic LAA closure during bioprosthetic aortic valve replacement appears safe from a bleeding perspective in the short term. However, the lack of statistical significance in the primary endpoint and the crossing hazard ratios suggest no clear benefit or harm in the 30-day window. The observed increase in postoperative atrial fibrillation with closure, while not statistically significant, warrants consideration when counseling patients about potential rhythm-related consequences. The short follow-up period limits conclusions about long-term stroke or mortality outcomes.

# Klinik önem

These findings suggest that prophylactic LAA closure can be performed without increasing 30-day bleeding complications during bioprosthetic aortic valve replacement. However, the procedure does not demonstrate a statistically significant reduction in the primary composite endpoint of cardiovascular death, stroke, or systemic embolism at 30 days. Clinicians should weigh the potential reduction in thromboembolic risk against the observed increase in postoperative atrial fibrillation and the lack of long-term outcome data. The decision to perform routine prophylactic LAA closure should be individualized, considering patient-specific factors and the current absence of evidence for hard clinical endpoints.

# Sınırlılıklar

  • Open-label design without blinding may introduce performance and detection bias.
  • Short-term (30-day) follow-up only; no long-term stroke or mortality data are reported.
  • Wide confidence intervals around hazard ratios (e.g., 0.62-9.4 for early period) indicate imprecision.
  • The time-dependent treatment effect, with hazard ratios crossing at approximately 7 days, complicates interpretation of early versus late effects.
  • No long-term data on stroke recurrence, systemic embolism, or mortality beyond 30 days.
  • Conflict of interest status was not reported in the available abstract, limiting assessment of potential funding or institutional biases.