Impact of left atrial appendage morphology on thrombus formation after successful left atrial appendage occlusion: Assessment with cardiac-computed-tomography

Abstract

A standardized imaging algorithm by cardiac computed tomography angiography (cCTA) (LOVE-view) was used in 30 patients to evaluate the influence of different left atrial appendage (LAA) morphologies on development of thrombosis in the LAA 6 months after implantation of an occlusion device (Watchman or Amplatzer-Cardiac-Plug) in patients with non-valvular atrial fibrillation, CHA2DS2-VASc-Score >1 and a contraindication for oral anticoagulation. The distribution of different LAA morphologies was 40% windsock, 17% broccoli and 43% chicken wing type. There was no significant difference in the level of thrombosis regarding LAA morphology or the type of chosen occlusion device. The rates of complete LAA thrombosis was 40% in broccoli type, 33% in windsock and 15% in chicken wing type. Independently of LAA type, 13% had none and 60% incomplete thrombosis. The ratio of density (LA/LAA) was 0.14 in patients with complete thrombosis and 0.67 in those with none or incomplete thrombosis. cCTA and the LOVE-view-imaging-algorithm were shown to be a valuable method for standardized imaging in clinical routine in a greater set of patients. Surprisingly thrombosis of the occluded LAA was still in progress in most cases at 6 months, whereas further studies are needed defining its clinical consequences, especially for the selection of the optimal post-procedural antithrombotic treatment strategy.

A simple method to detect leaks after left atrial appendage occlusion with Watchman

“…Earlier studies have reported chicken‐wing shape to be a challenging LAA morphology for Watchman deployment with significant impact on implantation success and compression ratio 16 . Furthermore, in a study by Dieker et al, 17 rate of complete thrombosis in the LAA was the lowest in the chicken‐wing type, which was in agreement with our data.…”

CT assessment of the left atrial appendage post-transcatheter occlusion – A systematic review and meta analysis

“…The prevalence of LAA patency was 67% among patients in studies using delayed phase imaging compared with 60% in those using only early phase imaging. (10,12,13,14,20,21,22,23,24) (Supplementary file; table). Two studies (11,25) reported LAA assessment in early and delayed phase techniques, which detected a 25% to 50% higher prevalence of LAA patency on the delayed imaging.…”

“…Clinical outcomes, including stroke, TIA, or DRT, were reported in 14 studies. (10,12,13,14,15,16,17,18,19,20,21,22,23,24) None of these compared outcomes between patient groups based on the presence or absence of LAA patency or DRT. Moreover, a wide clinical follow-up span was observed, with a median value of 377.5 (222-758.3) days.…”

Acute Device-Related Thrombus after Watchman Device Implant

“…Despite using this regimen, thrombus formation on the Watchman device is not uncommon. Predisposing factors for the development of thrombus are multifactorial including patient- and device-related factors [4]. These factors include but are not limited to prior thromboembolism, high CHA2DS2-VASC score, and deeply implanted device or large device [5, 6].…”