Mechanical thrombectomy is indicated for patients with acute ischemic stroke due to a large artery occlusion in the anterior circulation who can be treated within 24 hours of the time last known to be well.

Patients eligible for intravenous thrombolysis treatment should receive intravenous thrombolysis even if endovascular treatments are being considered and patients should receive endovascular therapy with a stent retriever if they meet all the following criteria:

• Patient’s previous status before stroke is independent (able to do a daily life activity and walk by own self).
• Patients eligible for intravenous thrombolysis treatment should receive intravenous thrombolysis before mechanical thrombectomy within 4.5 hours after onset.
• Vascular imaging of brain shows occlusion of large intracranial vessel.
• Age more than 18 years old.
• Severity of stroke should be moderate to severe by physician’s neurological examination (a deficit on the National Institutes of Health Stroke Scale or NIHSS of equal to or greater than 6 points).
• Brain imaging shows no evidence of large area brain infarction (Alberta Stroke Program Early Computed Tomography Score or ASPECTS of equal to or greater than 6).
• Mechanical thrombectomy should be done within 24 hours after onset of stroke.

The main goal of early treatment of acute ischemic stroke is to recanalize occluded vessel for brain reperfusion. Mechanical thrombectomy uses catheters to directly deliver a clot disrupting or retrieval device to a thromboembolus that is occluding cerebral artery.

A nurse will clean and shave the area where the catheter will be inserted.

General anesthesia or conscious sedation may be used for the procedure. Catheterization is performed with a femoral artery puncture. The catheter is guided to the internal carotid artery and beyond to the site of the intracranial large artery occlusion with the use of radioactive substances. The stent retriever is then inserted through the catheter to reach the clot. The stent retriever is deployed and grabs the clot, which is removed as the device is pulled back.

The patient is closely monitored in an intensive care unit for few days and stay in hospital for a week for observing recurrent stroke and post procedural complication. The patient will need to lie flat on the back and keep the legs straight and still for hours as doctor’s instruction to prevent bleeding.

• New ischemic stroke in a different vascular territory
• Symptomatic intracranial hemorrhage
• Anesthetic and contrast related
• Device-related serious adverse events such as arterial perforation, arterial dissection
• Pseudoaneurysm
• Access site hematoma
• Transient intraprocedural vasospasm
• Bleeding, infection or painful at the insertion site

From meta-analysis, the patient receiving mechanical thrombectomy has 20% higher rate (1.6 times) of functional independence when compared to standard treatment without mechanical thrombectomy.

• It is not recommended to travel by plane during first two weeks.
• It is recommended to stay close to the hospital in case of emergency and follow-up appointments.

The rate of spontaneous recanalization from mechanical thrombectomy is 84 percent when compared to standard intravenous thrombolysis which is only 46 percent. However, the patient should discuss with the doctor before the procedure.
 
What if the procedure is not performed?
The patient has a lower chance for recanalization of occluded vessel and less chance for recovery to mild deficit after stroke.
 

No standard alternative treatment other than mechanical thrombectomy in patient eligible for mechanical thrombectomy.