A case report by Vikram Huded, Narayana Institute of Neurosciences, Bangalore, India, and published online in BMJ Case Reports, has suggested that, if medical management fails, after identification of a thrombus in the vertebral artery, then endovascular intervention—the crossover balloon technique—is safe.
Huded and colleagues said that currently there are “no clear guidelines for endovascular treatment if a patient fails medical management.” Therefore the authors reported on a novel technique used to prevent embolization of vertebral thrombus during endovascular intervention.
The novel technique was undertaken after the patient, National Institutes of Health Stroke Scale (NIHSS) score of four increased to five (and increase in the infarct in the cerebellum and brainstem) and failed medical mangament. The authors reported that the patient, CT angiography “showed a right sided V2 segment narrowing with a floating thrombus distal to it. The rest of the vertebrobasilar circulation was normal. He also had a high-grade stenosis of the left internal carotid artery.”
Huded et al, in order to avoid embolization of the clot to the basilar artery, employed the crossover balloon technique for endovascular clot retrieval.
Crossover balloon technique
The authors accessed the bilateral femoral artery using a 6F sheath and a 6F guiding catheter was introduced into the right vertebral artery, which was followed by another 6F guiding catheter into the left vertebral artery.
Huded et al said: “A 5x15mm Hyperglide balloon (ev3) was negotiated from the left vertebral artery to the right vertebral artery and placed distal to thrombus via the verterbrobasilar junction. The balloon was inflated there by occluding the right vertebral artery distal to the thrombus, thus preventing the thrombus from embolizing into the basilar artery.”
“Mechanical aspiration of the clot was done through the guiding catheter, which was placed in the right vertebral artery using a 25ml syringe. Following mechanical aspiration, the right vertebral artery was stented using a 3.5x23mm bare metal balloon-mounted stent (Abbott Vascular) and the balloon stent was inflated to 8mm,” Huded and colleagues added.
According to the study, following stenting, mechanical aspiration was performed proximal to the Hyperglide balloon using Slipcath (Cook Medical) 125cm catheter and 25ml syringe. The Hyperglide balloon was then deflated and the post-procedure angiogram which, according to the authors, showed no residual narrowing and no evidence of thrombus.
Post-intervention, the patient was extubated and after 12 hours he complained of headache and was drowsy. A repeat CT showed cerebellar oedema due to earlier infarct. Therefore the patient underwent emergency posterior fossa decompression, however, after the procedure, his NIHSS score was four and his Barthel index improved from five to 65, according to the authors.
“Stenting of the vertebral artery in the presence of a thrombus is difficult owing to the risk of embolization, as is the case with placement of distal protection through the same artery,” said Huded et al. “We believe that, in patients with vertebral artery thrombus who fail medical management, this is a safe and novel technique.”