Sonothrombolysis for acute ischemic stroke - Break on through to the other side.

BACKGROUND: Intravenous (IV) tissue plasminogen activator (tPA) infusion combined with transcranial low-frequency ultrasound waves targeted on the occluded arterial segment (sonothrombolysis) can increase recanalization in large artery-acute ischemic stroke (LA-AIS).

AIMS: To evaluate the benefits of sonothrombolysis in LA-AIS.

SETTINGS AND DESIGNS: An open-labeled observational study done in a quaternary care teaching hospital.

METHODOLOGY: Patients with LA-AIS within the window period (<4.5 h) with no contraindications for IV-recombinant tPA were sonothrombolysed. Recanalization was monitored and graded using the transcranial Doppler thrombolysis in brain ischemia (TIBI) flow criteria and also by time of flight magnetic resonance angiography using a modified thrombolysis in myocardial infarction score. Parenchymal changes were assessed using computed tomography (CT) or diffusion-weighted imaging-Alberta Stroke Programme Early CT Score. National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) were used to assess the outcome.

RESULTS: Eighteen patients underwent sonothrombolysis and the mean onset to needle time was 138 min (range 65-256). TIBI residual flow grade of ≥2 was seen in 15 of 18 patients (83%). Immediate dramatic improvement (NIHSS score ≤3 points or improvement by ≥10 points) was seen in 6 of 18 patients (30%) and in 9 of 18 patients (50%) within the next 24 h. Two patients (one with TIBI 0, another with re-occlusion) underwent mechanical thrombectomy post-sonothrombolysis. Symptomatic hemorrhage occurred in 5.5% of the patients. At 6 months, 2 of 18 patients (11%) died and 10 of 16 patients (63%) achieved mRS ≤2.

CONCLUSIONS: Sonothrombolysis appears to be a safe way to augment the effect of tPA without increasing the door to needle time with the added advantage of observing flow through the occluded artery in real time.