Establishment of acute vertebral artery thrombosis models in dogs:micro-balloon catheter temporary isolation for embolectomy / 中国组织工程研究

ABSTRACT

BACKGROUND:In order to avoid distal arterial embolism fol owing mechanical thrombectomy, micro-bal oon catheter temporary isolation is applied to prevent thrombus shedding. OBJECTIVE:To investigate the safety and feasibility of adopting the micro-bal oon catheter technique in treatment of the hyperacute cerebral infarction. The micro-bal oon catheter technique can temporarily block the artery blood flow and isolate the embolism location fol owing mechanical thrombectomy and aspiration combined with thrombolysis. METHODS:Ten beagle dogs were included in this study. Under general anesthesia, the micro-bal oon catheter was delivered to the dominant vertebral artery through the femoral artery in al the dogs and it was fil ed and temporarily blocked the blood flow. Then the autologous thrombus was injected through the micro-catheter into proximal vertebral artery to make a thrombosis model. Al the dogs were equal y divided into two groups according to the embolectomy method:control group (receiving pure stent embolectomy, n=5) and experimental group (n=5). The experiment group was disrupted and aspirated thrombus combined with the drug thrombolysis after temporarily blocking out the blood flow and isolating the target artery by micro-bal oon catheter technique. After treatment, two groups underwent digital subtraction angiography to review the vertebral artery recanalization after different embolectomy methods. The hemodynamic status was evaluated through the thrombolysis in cerebral ischemia grade. Al the dogs were scanned with magnetic resonance diffusion weighted imaging before modeling and at 12 hours after the thrombectomy. The animals were kil ed to perform pathological examination after magnetic resonance diffusion weighted imaging (12 hours after the thrombectomy). The vessel recanalization rates and complications were calculated in the two groups. RESULTS AND CONCLUSION:The thromboembolism model was successful y established in the dominant vertebral artery of al the 10 beagle dogs. In the control group, the vertebral arteries were completely successful recanalized in two dogs and were partly recanalized in three dogs, while the vertebral-basilar and intracranial arteries in one dog showed multiple smal punctate fil ing defects with poor intracranial arterial development and contrast agent reflux. At 12 hours after embolectomy, the magnetic resonance diffusion weighted imaging showed slightly high signal intensity at the left temporoparietal lobe and the pathologic examination suggested thrombosis in the cerebral artery lumen of the left temporal lobe. In the experimental group, the vertebral arteries in five dogs were completely recanalized without infarction. The revascularization rate in the experimental group was significantly higher than that in the control group (P<0.05). Experimental findings indicate that, the application of disruption and aspiration thrombus combined with the drug thrombolysis after temporarily blocking the blood flow and isolating the target artery by micro-bal oon catheter technique in treatment of hyperacute cerebral infarction, can effectively prevent the smal embolus exfoliating, which can cause distal embolization. Thus, the micro-bal oon catheter technique is a safe, effective and relatively inexpensive interventional embolectomy.