Anatomical and Imaging Predictors of Peri‐Device Leak Following Left Atrial Appendage Closure Using the LAmbre Device: A Comparative Study of CCTA and TEE

BACKGROUND: Peri-device leak (PDL) is a recognized finding following left atrial appendage closure (LAAC) and may influence device efficacy. Transesophageal echocardiography (TEE) is routinely used for surveillance but may have limited sensitivity for small or concealed leaks. Cardiac computed tomography angiography (CCTA) provides high spatial resolution and three-dimensional reconstruction. This study compared CCTA and TEE for PDL detection after LAAC with the LAmbre device and examined anatomical distribution and evolution. METHODS: Eighty-two consecutive patients with nonvalvular atrial fibrillation underwent successful LAmbre implantation between 2018 and 2020 and were followed for 12 ± 1.2 months. At 3 months, all patients underwent TEE and contrast-enhanced CCTA. PDL was defined using attenuation-based criteria on CCTA. Procedural characteristics, including cover disk position and repositioning attempts, were analyzed in relation to PDL. RESULTS: At 3 months, CCTA identified PDL in 30 patients (36.6%), whereas TEE detected PDL in 15 patients (18.3%). Most leaks were localized to the pulmonary vein-mitral valve region. PDL occurred more frequently when the cover disk was positioned external to the pulmonary vein ridge compared with intraridge placement (64.3% vs. 22.2%; odds ratio 6.30, 95% CI 2.31-17.20; p = 0.048). All leaks measured < 5 mm. At 12 months, persistent PDL was observed in five patients (6.1%). CONCLUSION: CCTA identified more small PDL than TEE at early follow-up. Cover disk positioning relative to the pulmonary vein ridge was associated with PDL. Our findings should be interpreted in the context of the retrospective, single-center design and limited event numbers.