Before we delve into the details regarding thrombolysis and mechanical thrombectomy, it is necessary to get acquainted with some facts regarding stroke.
A stroke[1] is an acute vascular event of which there are 2 main kinds. In ischemic stroke, there is a block in the brain’s blood vessel which stops blood flow to the brain. Without blood flow, the brain cells start to die. An ischemic stroke is what happens in 80% of stroke cases.
In hemorrhagic stroke, there is a bleed in the brain. This happens in 15% of stroke cases. A bleed usually happens due to high, untreated blood pressure. This bleed too damages the brain cells.
In rare occasions, an aneurysmal rupture can lead to a stroke. When the blood vessels in the brain are weak, they tend to bulge and with the passage of time they rupture, bleeding into the brain.
Identifying a Stroke
FAST – Face, Arm, Speech, Time
The above acronym is something all of us must keep in mind to help us identify a stroke.
Face – Observe the patient’s face. If the mouth seems deviated to one side or in other words if the smile seems uneven, it is a symptom of a stroke.
Arm – Ask the patient to lift both arms. If the patient feels weakness in one of the arms, it is another symptom of concern.
Speech – Listen to them talk. If their words seem slurred, it is another stroke symptom.
Time – Time is of essence. Even if any one of the above symptoms are observed, it warrants an immediate hospital visit.
In a few cases, there are problems encountered with the eyes and balance as well. Hence this requires a slight addition to be made to the above acronym to BE-FAST.
B – Observe the patient for any balance or coordination issues.
E – Eye symptoms like blurring or vision loss are also signs of a stroke.
Also Read: Be ‘FAST’ On Managing Stroke[2]
Predicting a Stroke
Often, before a stroke happens, there are a few warning signs that might be missed because people are not aware of them. Being aware will help us predict and prevent a stroke.
In the case of an ischemic stroke, a TIA (transient ischemic attack or temporary stroke) might be experienced ahead of the stroke.
During a TIA, the patient will experience weakness, vision loss and speech loss. These symptoms tend to resolve themselves and as a result the patient might ignore these very important warning signs. 35% of such cases suffer a stroke within a year.
In case of a hemorrhagic stroke, the patient will experience severe headache (thunderclap headache) which will resolve itself with 1-2 minutes. However, this headache might be followed by neck pain and sometimes the patient might also experience loss of consciousness.
In some cases, stroke can also cause cognitive, behavioural and emotional changes along with memory problems. In the elderly[3] especially, these changes tend to be ignored as an inevitable part of aging. However, these are warning signs of a possible stroke and it is best to get the person evaluated.
Treatment Options for Ischemic Stroke – Thrombolysis and Mechanical Thrombectomy
Treatment for an ischemic stroke differs from a hemorrhagic stroke.
For an ischemic stroke[4], the block which is preventing the flow of blood to the brain needs to be broken down.
Time plays a huge role as bringing the patient to a hospital within 4 ½ hours of stroke onset can change the prognosis. Hence these 4 ½ hours are rightfully called the golden hours.
Once the patient reaches the hospital, a CT scan will be done and if it is normal, the neurologist will take steps to break the clot to resume blood flow.
There are two drugs for this – RTPA and Tenecteplase. The exact drug will be decided on by the neurologist[5]. This process of clot breakdown with medication is called thrombolysis.
Thrombolysis will not be done if the patient has high blood pressure, is pregnant, has undergone a recent surgical procedure, is on blood thinners, has suffered recent head trauma or if he/she has bleeding problems.
When the doctor decides that thrombolysis can be carried out, it is crucial that the drug be administered within 4 ½ hours of stroke onset. This is because beyond 4 ½ hours, the drug will manifest severe side effects.
After drug administration, 60-70% of the time, the patient will return to near normalcy. In cases wherein the patient does not show improvement, he/she will be shifted to the cath lab.
In the cath lab, a dye is injected to locate the block.
Once the clot has been localized, using a special catheter, the clot will be removed mechanically by a process called mechanical thrombectomy. After the clot has been removed, blood flow to the brain will resume.
Keep in Mind
Thrombolysis has to be done within 4 ½ hours of stroke onset.
A mechanical thrombectomy can be done for up to 6-12 hours after stroke onset. In some very rare cases, even till 24 hours it is done.
The procedure of mechanical thrombectomy is done in all comprehensive stroke care centres.
As Always, Prevention Is Better Than Cure
Stroke prevention is possible – all it takes is a little effort. The following lifestyle changes will go a long way towards stroke prevention:
Make healthy diet a part of your lifestyle. Plant based food, fish and poultry products (for non-vegetarians) are recommended.
Be active – set aside some time for exercise every day. At least 30 minutes a day for 5 days in a week would be ideal.
Quit alcohol and smoking.
Learn to manage stress. Brighten up your workspace and avoid multitasking.
Make sure BP and sugar are within range.
Make the above-mentioned changes today to help prevent a possible stroke attack in the future.
Reviewed by Dr Suresh S Venkita, Group Medical Director, Kauvery Hospitals
Kauvery Hospital is globally known for its multidisciplinary services at all its Centers of Excellence, and for its comprehensive, Avant-Grade technology, especially in diagnostics and remedial care in heart diseases, transplantation, vascular and neurosciences medicine. Located in the heart of Trichy (Tennur, Royal Road and Alexandria Road (Cantonment), Chennai, Hosur, Salem, Tirunelveli and Bengaluru, the hospital also renders adult and pediatric trauma care.