Trans-catheter left atrial appendage (LAA) occlusion with a Watchman device (WM) (Boston Scientific Corp, MA, USA) is a feasible alternative to long-term anticoagulation for stroke prevention in patients with non-valvular atrial fibrillation (AF). Cardiac computed tomography angiography (CCTA) is routinely used to asses LAA morphology and determine the size of the WM. Trans-esophageal Echocardiography (TEE) may identify minor peri-device leak (PL) that are supposed to be filled later. We sought to assess the mid term evolution of PL.

Implantation of a WM was attempted in 74 patients, successfully in 70. CCTA was performed >45 days after implantation in 44 patients. We compared immediate results of the procedure by TEE to late results by CCTA performed >1 month after implantation.

Late CCAT was done in 44 patients, 28 male (64%), mean aged 77 years (57–92). Indications for LAA closure was bleeding in all cases, neurologic in 18 (45%), gastrointestinal in 16 (36%) and miscellaneous in 8 (18%). CHA2DS2-VASc score was 5 (3–9). Anticoagulation was contraindicated in all cases. An anti-platelet agent was given in 37 and no treatment in 7 (16%). None of these patients had had any thromboembolic event at the time of CCTA. A PL was identified by TEE at the time of implantation in 20 pts (45%) and by late CCTA in 22 pts (50%). In 17 pts with a CCTA done >6 months, 7 had a PL (41%). Late PL was noted in 10 patients with (50%) and 12 patients (50%) without early PL.

Early PL seems to remain at mid-term in half of the patients. Moreover, TEE could be unable to detect PL that is identified by CCTA later in 1 case over 2. Nevertheless the clinical consequence of PL seems to be marginal in this study and the literature.