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Let's talk about Strokes
A cerebrovascular accident (CVA), commonly referred to as Stroke, is a neurological disease that results from the interruption of blood supply to a specific part of the brain. This blockage alters the correct functioning of the brain and results in cell damage, ultimately leading to the death of the brain tissue itself. The interruption can originate from two distinct situations and for this reason two types of stroke are distinguished:
- Ischemic Stroke — This is the most common type of stroke, accounting for about 80% of cases. It results in the obstruction of the blood flow, usually due to a blockage of an artery in the brain, thus preventing the supply of blood to a specific part of that organ;
- Hemorrhagic Stroke — Less frequent, this type of stroke results from the rupture of an intracranial artery, leading to blood leakage that damage the brain tissue.
Sometimes, « mini strokes” can occur, the so-called Transient Ischemic Attack (TIA), in which there is a small momentary interruption of the blood supply to a certain part of the brain, which is quickly restored. Although in these episodes the brain tissue does not die due to the lack of blood supply and the brain function is quickly restored, they should be seen as a warning sign as they may indicate that an Ischemic Stroke may be imminent.
It is amongst the older community that strokes are more common, affecting women more than men, with women representing almost 60% of stroke deaths.
Every year, 15 million people suffer a stroke, of which 6 million do not survive the episode. In Portugal strokes are the leading cause of death, with the country having the highest mortality rate in all of Western Europe. The incidence of the disease is about 25,000 people per year, of which about 10% result in death and about 35% result in high disability. Once the blood supply is shut off to a certain part of the brain, the brain cells responsible for specific functions can become damaged and unable to fulfill their function, thus causing long-term disability.
Even though the incidence of stroke is decreasing, possibly a reflection of the increased awareness of the population regarding the control of arterial hypertension and the high levels of cholesterol, we can further reduce the number of incidences and fatalities, with a focus on prevention and rapid diagnosis and treatment, which result in effective recovery from the stroke and the resumption of cognitive and motor functions.
The symptoms of a stroke can vary greatly depending on the type of stroke suffered (ischemic or hemorrhagic) and the part of the brain affected, however, as episodes usually occur suddenly, their effects are usually immediate. Since the extent of damage caused by a stroke is closely linked to the length of medical practice, it is essential that the population knows its most typical symptoms:
- Facial asymmetry – the face drooping to one side, usually the mouth;
- Difficulty in speaking – inability to find the right words and lack of articulation in word formulation;
- Lack of strength – sudden weakness or paralysis of one side of the body, such as a leg or arm, or even an entire side of the body.
These are generally the symptoms most associated with stroke and that we need to look out for.
In case any of these symptoms is revealed, the person should be immediately directed to nearest hospital or medical center. Don’t wait for the symptom to go away.
Strokes may also be accompanied by other symptoms that also deserve the same degree of urgency in their observation:
- Sudden and severe headache;
- Loss or reduction of sensitivity on one side of the body or limb (for example not identifying the sensation of cold or heat);
- Sudden confusion, with difficulty in understanding the language or place where you are;
- Sudden change in vision, with obscured and blurred vision or loss of vision (particularly in one of the eyes);
- Sudden dizziness or loss of balance and coordination, with the body leaning to one side or dragging one leg;
- Tremors or unusual and uncontrolled movements;
- Sudden drowsiness or loss of consciousness;
- Memory loss and mental confusion;
- Nausea and vomiting;
- Sudden very high blood pressure.
However, strokes can happen without revealing any visible symptoms. Only after carrying out routine exams or for any other reason, it is noticed that the person has suffered a stroke. For this reason, people that present some of the risk factors should have regular consultations with their doctor.
The main causes for a stroke are largely related with the risk factors, factors which can be corrected through changes in lifestyle habits or by taking medication. The most prevalent risk factors are:
- Dyslipidemia (high cholesterol levels)
- Insulin resistance
- Excess weight
- Obesity (especially fat accumulated around the abdomen)
- Sedentary lifestyle
- Cardiac arrhythmia
- Sleep apnea
- Infectious endocarditis
- Vasculitis (inflammation of blood cases)
- Use of drugs such as cocaine or amphetamines
There are still other risk factors that we are unable to respond to, such as age, sex and genetic inheritance (the latter not only due to the influence of the family’s health history but also the genetic characteristics of each ethnic group).
The diagnosis for a stroke is suggested by the combination of the symptoms observed and the results of a physical examination performed by a physician. However, in order to be able to understand exactly whether a stroke occurred and whether it was ischemic or hemorrhagic, several medical exams must be carried out:
- Computed tomography (CT) or magnetic resonance imaging (MRI) – this exam allows you to see if a stroke has occurred and what type of stroke, the affected region of the brain and to estimate how long ago it occurred. It also allows to visualize if the arteries are obstructed by a clot or if there are signs of increased intracranial pressure;
- Laboratory tests – the blood sugar level should be measured immediately, as an event of hypoglycemia (low blood sugar) can cause the same symptoms as a stroke;
There are other imaging tests, such as CT angiography or diffusion-weighted MRI that also allow you to assess the extent of damage caused by the stroke.
The doctor should always look for the cause of the stroke, and should therefore order several additional tests, such as:
- Electrocardiograms (ECG), echocardiograms and blood tests to rule out cardiac influence;
- CT, MRI and ultrasound to visualize the blood vessels that run from the heart to the brain;
- Blood tests to screen for diseases that coagulate the blood or blood oxygenation levels;
- Urine tests, to rule out drug use.
Based on these tests the physician is able to assess the degree of urgency of the intervention and what type of intervention should be performed, what is the need and degree of rehabilitation to be carried out, as well as instructing the patient on ways to reduce the chances of new a stroke.
After diagnosis, doctors are able to determine the severity and type of stroke and how it should be responded to. The entire process must be carried out as quick as possible, since for every 15 minutes of delay in treatment the risk of fatality increases by 4%. For this reason, early hospitalization is essential. Once the patient is admitted, there is a critical time window of action that will allow for effective treatment and decrease the risk of complications and recurrence.
If the patient is diagnosed with an Ischemic Stroke, the most common, the treatment may include:
- Administration of anticoagulant and antiplatelet drugs, as well as drugs to control hypertension;
- Intravenous Thrombolysis – Intravenous administration of drugs that will dissolve the clot that is obstructing the cerebral artery. This procedure must be performed within the first four and a half hours after the onset of symptoms, with a serious risk of hemorrhage after this time window;
- Intra-arterial Thrombolysis – surgical procedure in which a catheter is inserted usually into an artery in the groin, which should reach an artery in the neck and a drug that will dissolve the clot is then passed through this tube;
- Mechanical Thrombectomy – surgical procedure in which a catheter is inserted usually in the groin, which should reach an artery in the neck and a mechanical instrument is then passed through this tube to physically remove the clot;
- Angioplasty – surgical procedure in which a catheter is inserted usually in the groin, which should reach an artery in the neck and then a mechanical instrument (small balloon) is passed through this tube, which should widen and unblock the artery. Angioplasty can also include the placement of a stent, which is a small metal mesh that should be installed in the artery to prevent it from becoming obstructed once more;
- Endarterectomy – surgical procedure that aims to remove the fatty deposits in the arteries of the neck that obstruct them.
If the patient is diagnosed with Hemorrhagic Stroke, the treatment will be different from the previous one and may include:
- Administration of coagulant drugs to stop the bleeding. Transfusions of fresh frozen plasma or platelets can also be performed;
- Administration of medicines to control hypertension;
- Surgical procedure on the skull to remove large amounts of blood or place a drain to relieve accumulated pressure;
- Surgical procedure in which small spirals or stents are inserted through a catheter that should block the rupture of the blood vessel that is causing the bleeding.
The patient’s rehabilitation program should start soon after admission, thus reducing stroke sequels.
As with any other diseases, prevention is always preferable to treatment. In the case of strokes, this maxim is no exception, so we must be alert and vigilant to the modifiable risk factors that increase the likelihood of a stroke.
Therefore, we must all seek to implement improvements in our lifestyle and control illnesses and health problems that may aggravate stroke risks:
- Practice physical exercise, as a way to control excess weight and accumulated fat, as well as the blood pressure;
- Control LDL cholesterol levels, the so-called “bad cholesterol”, through dietary changes and reduced intake of saturated fats that increase the risk of clogging arteries;
- Avoid drinking alcohol, smoking, and consuming stimulant drugs such as cocaine and amphetamines, which dramatically alter blood flow.
People suffering from diseases such as diabetes, high blood pressure and heart disease should take extra care in monitoring their health condition, having regular medical examinations, ideally every year.
How to avoid a new stroke?
After the occurrence of a stroke, it is extremely important to take measures that reduce the chances of a new episode. Cardiac exams and brain imaging exams should be performed, as well as clinical analyzes with variable frequency. The patient must also be monitored in a clinical environment in order to monitor associated risk factors.
A large number of patients after a stroke need to take preventive medication, usually for life. The aforementioned lifestyle changes for prevention should also be adopted.
What can be the sequels of a stroke?
As already mentioned, the degree of severity and duration of the sequelae resulting from a stroke episode are closely linked to the time that elapses until its treatment. The faster the patient is treated, the less severe the sequels and the better the chances of recovery.
The severity and duration of the sequels are also and to a certain extent dependent on the type of stroke suffered (ischemic or hemorrhagic), as well as the area of the brain that was affected.
Generally speaking, a small Hemorrhagic Stroke episode without great intracranial pressure can be less aggressive than a similar episode but with Ischemic Stroke, this because the inflow of blood in an area of the brain causes less damage to the brain tissue when compared to the inhibition of oxygen to that area.
If the stroke affects a highly important area of the brain, such as areas that affect speech or motor functions, recovery can be particularly difficult and time-consuming. In situations where the brain is affected in the areas responsible for the motor functions, a high degree of dependence on others to perform simple tasks such as eating, dressing or walking can develop. These situations can also be responsible for the development of depression. Depression can and must be treated.
Recovery time varies from patient to patient and also due to the specific characteristics of each episode.
In order to reduce the impact of stroke sequels, the rehabilitation process should be started right after admission, usually one or two days after arrival. Physical therapy exercises to improve movement, speech therapy sessions to improve communication and occupational therapy sessions should be started. With these practices, it is intended that the patient recovers as much as possible his abilities to perform daily tasks and activities, that he maintains his physical shape and that his quality of life improves, while also intending that the body and brain are re-educated, relearning old skills and possibly learning some new ones.
The effectiveness of these processes and sessions depend a lot on the patient’s willpower and perseverance, as they do not end when leaving the hospital. This should be an ongoing process that goes through sessions in a rehabilitation center, physiotherapy and occupational therapy centers, as well as the practice of exercises at home and in everyday life.
It is important to recognize that currently people who suffer from a stroke have a greater chance of recovery and a decrease in the severity and duration of the sequels due to the greater ease and speed of response, treatment and follow-up in emergency situations in the so-called stroke units of hospitals.
Centers for Disease Control and Prevention
Viver após um Acidente Vascular Cerebral – Recomendado aos Prestadores de Cuidados Informais, Direcção-Geral da Saúde, Lisboa, 2000
Sociedade Portuguesa de Cardiologia
Sociedade Portuguesa do Acidente Vascular Cerebral