Clinical outcomes and thrombus resolution in patients with solid left atrial appendage thrombi: results of a single-center real-world registry

Data on thrombus resolution and clinical outcome data after a therapy of LAA thrombus with novel oral anticoagulants (NOACs) are scarce. In this single-center study, we retrospectively analyzed 78 patients diagnosed with a solid LAA thrombus by transesophageal echocardiography (TEE). We assessed baseline clinical and echocardiographic characteristics, the anticoagulatory regimens and outcomes of patients with (responders) and without (non-responders) thrombus resolution. Mean age was 76.1 ± 8.3 years, patients were male in 57.7% and presented with a high risk for thromboembolism (CHA2DS2-VASc: 4.3 ± 1.1). At thrombus diagnosis, 44.9% patients were treated with a NOAC, while 41.0% were under therapy with a VKA. Complete thrombus resolution was achieved after a mean of 116 ± 79 days in a total of 51.3% of patients, 35.9% showed a reduction of thrombus size, whereas 12.8% showed no changes in thrombus dimensions. There was no statistically significant difference in the rate of LAA thrombus resolution between VKA and NOACs (41.2 vs. 57.1%, p = 0.18). However, in cases in which only the therapy with a NOAC led to complete thrombus resolution, the time needed was significantly shorter than with VKA (81 ± 38 vs. 129 ± 46 days, p = 0.03). Regarding safety outcomes, no differences in bleeding or thromboembolism were observed between patients with and without thrombus resolution. In this registry, approximately 85% of LAA thrombi were diagnosed in patients with ongoing OAC. Thrombus resolution was observed in nearly 50% of cases. Although there was no difference in the rate of LAA thrombus resolution between VKA and NOACs, the resolution time was shorter in patients prescribed a NOAC.