Jennifer Dearborn, MD

Barreto AD, Alexandrov AV, Shen L, Sisson A, Bursaw AW, Sahota P, et al. CLOTBUST-Hands Free: Pilot Safety Study of a Novel Operator-Independent Ultrasound Device in Patients With Acute Ischemic Stroke. Stroke. 2013


Most would agree that timely recanalization is an important to maximize recovery during acute stroke. This is the goal of t-PA, and we need an adjunctive therapy to improve its efficacy. Sono-thrombolysis is an intriguing alternative, because it is non-invasive, performed at the bedside and provides no radiation exposure. A problem in administration is that it can be technically difficult and operator dependent, requiring the skill of a technician that may not be available 24-7. This is the rationale of the CLOTBUST hands-free device which is operator independent and provides 2 hours of exposure to ultrasound waves.


In this article, Barreto et al. demonstrate that the hands free device is safe in the 20 participants tested (intracranial hemorrhage is the endpoint). Participants presented as an acute stroke and received IV-tPA. They had a demonstrated large vessel occlusion by either TCD or CT angiogram (MCA, ICA or vertebral). The device was placed after the t-PA bolus was administered and left on for 2 hours. At the end of the therapy, subjects underwent repeat TCD or CTa to determine recanalization by TIBI criteria. One subject did have a symptomatic ICH, however that was attributed to endocarditis and not the study device. Recannalization rates were similar to historical controls in the t-PA group.

It is not surprising that this technology is safe. Early recanalization does carry a risk of hemorrhage, but also the greatest potential for benefit for recovery. This technology can be delivered rapidly and upon presentation to the emergency department. We are still left with the question; does it work to improve outcomes in stroke patients? We will have to wait for the next phase to find out.