Impact of Device Compression on Peridevice Leak After Left Atrial Appendage Closure: The Impression LAAC Study.

Background Left atrial appendage closure (LAAC) is an established therapeutic strategy to prevent ischemic stroke in selected patients with atrial fibrillation. However, residual peridevice leaks (PDLs) post-LAAC remain a critical concern.Objectives This study sought to assess the clinical impact of Watchman FLX device overcompression.Methods Data on consecutive patients undergoing a transesophageal echocardiography (TEE)-guided LAAC between 2020 and 2023 in 2 high-LAAC volume centers were collected and patients with a device compression higher (overcompression group) or lower (normal compression group) than 30% as evaluated by procedural TEE were compared in terms of procedural complications, composite of cardiovascular death, ischemic stroke, or systemic embolism, and PDL at TEE follow-up.Results This study included 61 overcompression and 175 normal compression patients. Baseline and procedural characteristics did not differ between the 2 groups. Both composite of procedural complications (1.6% vs 1.7%; P = 0.968) and of cardiovascular death, ischemic stroke, or systemic embolism during follow-up (9.8% vs 12%; P = 0.971) did not significantly differ between the 2 groups. At 2-month TEE follow-up, the rate of residual PDL was significantly lower in the overcompression group (8.2% vs 32.6%; P < 0.001). At the multivariate analysis, the device compression rate was the only variable independently associated to risk of PDL at TEE follow-up (adjusted OR: 0.935; 95% CI: 0.927-0.948; P = 0.003).Conclusions In this dual-center cohort of TEE-guided LAAC, the overcompression group was independently associated to a higher rate of LAA occlusion at TEE follow-up.