Syncope is a temporary loss of consciousness caused by a decrease in bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood flow to the brain. It can have multiple causes, which vary depending on the individual and the circumstances.
Read more: Syncope or loss of consciousnes
Syncope or carotid sinus syndrome
Syncope related to carotid sinus syndrome is a type of reflex syncope, meaning a brief loss of consciousness caused by an overreaction of the autonomic nervous system.
Pressure “Sensors” in the Carotid Arteries
In this type of syncope, the trigger is located in the carotid arteries, found on either side of the neck.
These bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood vessels carry oxygen-rich bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood from the heart to the brain and are equipped with pressure sensors known as baroreceptors.
Their role is to detect any excessive rise in bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood pressure and activate a reflex mechanism to lower it, helping to protect the brain’s bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood supply.
Special circulatory system
The brain, for its part, benefits from a unique bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood circulation system. The amount of bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood it receives does not directly depend on the pressure measured in the arteries.
To explain this, we can compare it to a garden hose: no matter the pressure at the start, the flow of water coming out remains stable.
This phenomenon, known as cerebral autoregulation, allows for a constant bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood flow to the brain as long as the mean arterial pressure (MAP) stays between 50 and 150 mmHg. This average is calculated using the following formula:
(Diastolic Pressure x 2 + Systolic Pressure) ÷ 3
For example, if your bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood pressure is 120/80 mmHg, the average is about 93 mmHg.
In people with chronic high bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood pressure, this protective system can become impaired. The brain then becomes more sensitive to sudden pressure changes, increasing the risk of fainting during an abrupt imbalance.
Hypersensitivity
In some people, these pressure receptors become abnormally sensitive.
A simple stimulation of the neck—such as shaving, wearing a tight shirt collar, or making a sudden head movement—can be enough to trigger a slowing of the heart rate, a drop in bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood pressure, and ultimately, a fainting episode.
This type of syncope occurs almost exclusively in people over the age of 40.
Exaggerated Blood Pressure Spike
A similar phenomenon can occur in bodybuilders, especially during intense weightlifting with very heavy loads.
Sustained effort causes a significant rise in bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood pressure, which strongly stimulates the pressure sensors in the carotid arteries.
To protect the brain from this sudden spike, the body responds by slowing down the heart rate and rapidly lowering the pressure. This reflex can lead to symptoms such as dizziness, nausea, and even vomiting.
Needless to say, this kind of extreme effort, especially when done without proper supervision, is not recommended.
What Tests May Be Ordered?
Initially, an electrocardiogram (ECG) is usually prescribed. This simple test records the heart’s electrical activity and can detect any abnormalities in heart rhythm.
A cardiac ultrasound (echocardiogram) is often performed next. It provides images of the heart’s chambers, valves, and muscular movements, giving a clear picture of the heart’s structure and function.
Lastly, a 24-hour Holter monitor may be recommended. This small portable device continuously records the heart’s rhythm over a full day, offering valuable insight into how the heart behaves during everyday activities.
A more specific test
The main test used to diagnose carotid sinus syndrome is called the carotid sinus massage.
This procedure involves applying firm pressure to the carotid artery, located in the middle of the neck, in order to trigger the reflex that slows the heart rate. It is performed by an experienced physician, under electrocardiographic monitoring, in a controlled medical setting. It allows doctors to observe the heart’s response in real time.
It is strongly discouraged to attempt this maneuver at home, as it can lead to serious side effects if done incorrectly.
What Are the Health Risks?
The main risk lies in the possibility of injury from falling, especially if the syncope occurs in a dangerous location or when the person cannot sit or lie down quickly.
The Main Risk: Falling
As with other types of syncope, the greatest danger is the risk of injury due to a fall.
Depending on the circumstances, a sudden loss of consciousness can result in trauma—especially if the person falls onto a hard surface or is in a hazardous environment (e.g., stairs, while driving).
What Is the Treatment?
Treatment for carotid sinus syndrome depends on the severity of symptoms and their impact on quality of life.
In some people—particularly when syncopal episodes are frequent or carry a higher risk of complications—the implantation of a permanent pacemaker may be necessary.
This device helps prevent excessive slowing of the heart rate by maintaining a regular heartbeat, thereby reducing the risk of future fainting spells.
The decision to proceed with this type of treatment is always based on the results of medical tests and a comprehensive clinical evaluation by a healthcare provider.
Some Helpful Tips
For people living with carotid sinus syndrome, certain precautions can help prevent fainting episodes.
It is recommended to avoid any pressure or manipulation of the neck, such as during shaving, massages, or sudden head movements.
It’s also best to avoid wearing tight clothing around the neck, such as snug turtlenecks or neckties, to reduce the chance of unintentional stimulation of the carotid arteries.
These simple actions can help lower the risk of syncope and contribute to better day-to-day safety.
Related articles
Latest articles
