Mechanical thrombectomy

Mechanical thrombectomy

Mechanical thrombectomy is a treatment for acute occlusion of a cerebral blood vessel under X-rays guidance to check blood vessels in the brain and neck. During the procedure, the doctor will insert a small tube called a catheter into an artery that leads to the brain and neck area and inject contrast media while taking X-ray images to remove occluding clots from cerebral or neck blood vessels. 

This procedure consists of 5 main steps as follows:

1. Inserting a catheter: a physician cleans the insertion site of the catheter, typically the groin, wrist, or fold of the arms. Under local anesthetic, the doctor will insert a catheter into the artery. The patient may feel pressure or discomfort in that area. An image of the catheter traversing up the blood vessel will appear on the X-ray monitor (like a television screen).
2. Injecting contrast media: when the catheter is in the correct position, the physician will inject the contrast agent through the catheter. An image of blood vessels appearing on the X-ray monitor will be recorded. While injecting the contrast media, the patient may feel the warmth inside the artery (lasting about 2 – 3 seconds). In some people, several injections and multiple X-ray images are necessary for a thorough diagnosis of blood vessels.
3. Removal of a blood clot blocking the blood vessels in the brain: the physician inserts a catheter into an artery and stops at the site where the blockage occurs. A medium-sized catheter will be inserted to suck out a blood clot directly or place a stent retriever to grab the blood clot. Then, the catheter and the stent retriever, with the blood clot, are pulled out.

In case of cerebral artery stenosis or dissection, a physician may perform angioplasty and stenting to widen the affected artery.

4. Removing the catheter: when the procedure is complete, the catheter will be withdrawn. The removal is not painful. The physician will apply pressure on the puncture site for 10 – 15 minutes.
5. Patients who only receive local anesthetic will be transferred to a postoperative recovery room for 30 minutes to 1-hour observation. If there is no complication, they will go to ward areas for further monitoring. 

Patients who receive local anesthetic and sedative will be transferred to a postoperative recovery room for 2 hours of observation and to ward areas for further observation if there is no immediate complication.

The advantage of this treatment 

Nowadays, mechanical thrombectomy is the international standard for patients presenting with acute cerebral blood vessel occlusion meeting the criteria for the treatment.

Potential risks and complications

1. Bleeding
2. Infection
3. Injury at the site of blood vessel puncture
4. Reactions to contrast media
5. Acute thrombosis - if blood clots form and block the blood vessels in the brain, cerebrovascular accidents may occur; this has a very low incidence.
6. Reactions to intravenous sedation

Preparation before the procedure

1. Patients and their relatives receive information about the steps, benefits, and potential unwanted complications of the procedure.
2. Patients will be asked about their history of allergy to drugs, seafood, and preexisting diseases.
3. The physician will order a chest X-ray, blood tests to check for kidney function and blood coagulation, and EKG for patients aged 35 or older.
4. If a patient is on blood thinners such as aspirin, Plavix, and warfarin, they should inform their doctors because of the potential risk of bleeding and the need to apply prolonged pressure on the puncture site.
5. Patients will be asked to fast for 6 hours before the procedure.
6. The groin insertion site will be shaved.
7. Patients must sign the consent form for the procedure.

Aftercare

1. Receive continuing care in ICU
2. Keep your leg straight while lying flat for at least 8 hours.
3. Inform the nurses immediately if you notice numbness, coldness, or paleness on the arm or leg with a puncture site.
4. Apply a bandage to the puncture site for 8 hours. If it bleeds, you should lie down and notify the nurses.
5. If there are no complications within 8 hours, your doctor may discharge you.
6. Rest for 24 hours after the procedure.
7. You will receive intravenous fluid and check for swelling or redness at the puncture site. Another complication that can happen during recovery is a delayed contrast reaction.

Alternative treatments

Anticoagulant administration for acute stroke, based on appropriate indications. However, in the case of a large cerebral arterial blood clot, anticoagulants may not dissolve the blood clot completely, leaving patients with symptoms of cerebrovascular accidents and complications of cerebral ischemia.