Impact of Spontaneous Echo Contrast on Clinical Outcomes After Left Atrial Appendage Closure

Spontaneous echo contrast (SEC) with atrial fibrillation (AF) is known to increase stroke risk. However, the effect of SEC grades on outcomes after left atrial appendage closure (LAAC) remains unclear.

This study aimed to evaluate the impact of SEC grades on clinical outcomes after LAAC.

A total of 1,276 consecutive patients undergoing LAAC were analyzed. They were classified into SEC 0+, SEC 1/2+, and SEC 3/4+ groups based on preprocedural transesophageal echocardiography. Clinical outcomes were compared among the groups.

There were 595 (46.6%), 509 (39.9%), and 172 (13.5%) patients in the SEC 0+, SEC 1/2+, and SEC 3/4+ groups, respectively. The SEC 3/4+ group (11.5%) had a higher ischemic stroke/transient ischemic attack/systemic embolism incidence than the SEC 0+ (4.4%; P = 0.009) and SEC 1/2+ (5.4%; P = 0.047) groups; SEC grade, however, was not a significant predictor in multivariate analysis. Compared with the SEC 0+ group (2.8%), both the SEC 1/2+ (8.4%; P < 0.001) and SEC 3/4+ (12.4%; P < 0.001) groups were associated with a higher risk of device-related thrombus (DRT). When SEC grade and AF type were combined for assessment, SEC 3/4+ with nonparoxysmal AF was associated with both thromboembolic events (adjusted HR: 2.52; 95% CI: 1.22-5.20; P = 0.013) and DRT (adjusted HR: 2.89; 95% CI: 1.50-5.60; P = 0.003).

Patients with greater SEC grade displayed a higher incidence of thromboembolic events and DRT, and combined SEC grade and AF type independently predicted these events. Further research is needed regarding optimal treatment strategy in patients with severe SEC.