Microemboli post-thrombectomy does not affect outcome but signals embolic event recurrence

The presence of microembolic signals (MES) following successful endovascular treatment of anterior circulation occlusions has no bearing on clinical or radiological outcome, although it is a red flag for recurrence of embolic events within 90 days, a study has found.

A total of 111 consecutive patients with ischaemic stroke and occlusion of anterior circulation vessels underwent successful thrombectomy. They were subjected to 30 minutes of transcranial Doppler monitoring within 72 hours of the last-seen-well time to assess MES.

MES were detected in 43 patients (39 percent), with a median rate of 4 counts/hour (interquartile range, 2–12). There were no significant differences between patients with and without MES in terms of modified Rankin Scale (ordinal shift analysis: adjusted odds ratio [aOR], 1.06, 95 percent confidence interval [CI], 0.48–2.34; p=0.85) and functional independence (modified Rankin Scale, 0–2: aOR, 0.52, 95 percent CI, 0.19–1.39; p=0.19).

Likewise, infarct volumes on 24-hour computed tomography were similar in patients with and without MES (adjusted beta, 11.2, 95 percent CI, −46.6 to 22.9; p=0.51).

However, MES was a significant predictor of new embolic events (adjusted hazard ratio, 6.78, 95 percent CI, 1.63–27.8; p=0.01).

The present data suggest that the presence of microemboli in the acute stage is an important risk factor for further embolic events in the weeks and months after a stroke, researchers said. This information may prove useful in risk stratification and patient management.