What Is Neurocardiogenic Syncope?
Vasovagal syncope refers to various stimuli that mediate reflexes through the vagus nerve, leading to dilatation and bradycardia of small blood vessels in the viscera and muscles, sudden expansion of peripheral blood vessels, reduction of venous blood return to the heart, and a reflex action that accelerates and strengthens the contraction of the heart. In some people, excessive stimulation of the vagus nerve and parasympathetic nerves will cause the heartbeat to slow down suddenly and the peripheral blood vessels to expand. As a result, the blood pressure will decrease and the brain will be hypoxic. It will be manifested as arterial hypotension accompanied by a brief loss of consciousness, and can recover on its own. A syndrome without signs of neurolocalization.
Vasovagal syncope
- Vasovagal syncope refers to various stimuli that mediate reflexes through the vagus nerve, leading to dilatation of small blood vessels in the viscera and muscles and
- Syncope refers to a sudden loss of consciousness, accompanied by a decrease or disappearance of muscle tone, which lasts for several seconds to several minutes and recovers on its own. The essence is a temporary decrease in cerebral blood flow. Syncope can be
- Although Lewis has proposed the diagnosis of vasovagal syncope for nearly 70 years, its etiology and pathogenesis have not been fully elucidated so far. At present, most scholars believe that the basic pathophysiological mechanism is that the compensatory reflex of the autonomic nervous system in children is inhibited, and it cannot maintain cardiovascular function for a long time in an upright position.
- Vasovagal syncope is more common in school-age children, and more girls than boys. It usually manifests as sudden syncope during standing or sitting. There may be a short period of dizziness, inattention, paleness, vision, and hearing loss before onset. Nausea, vomiting, sweating, standing instability and other aura symptoms, severe cases may have aura of 10-20 seconds. If you can alert to this threat and lie down in time, you can ease or disappear. In the beginning, the heartbeat is often accelerated, and the blood pressure is still maintained. Later, the heartbeat is slowed, the blood pressure is gradually decreased, and the systolic blood pressure is significantly lower than the diastolic blood pressure.
- For a long time, the diagnosis of definite vasovagal syncope mediated by nerves has been indirect, time-consuming, and expensive, and often without clear results.
- For children with recurrent syncope, after a detailed history, the symptoms and signs at the time of the seizure, and then through the necessary auxiliary tests such as electrocardiogram, electroencephalogram, biochemical examination and
- There is still a lack of effective treatments and drugs for vasovagal syncope. For some high-risk groups who do not have prodromal symptoms and often experience sudden syncope and falls, especially those who have repeated trauma or are often exposed to vulnerable environments, preventive treatment is needed. The goal of treatment is to reduce the frequency of severe syncope events and reduce trauma. There are many ways to treat vasovagal syncope, which vary from person to person.
- Mission and lifestyle improvement
- Vasovagal syncope is often triggered by certain factors, and some may only occur in specific circumstances. Therefore, it is necessary to do a good job in the education of patients and their families, try to avoid these triggers, and try to stop them.
- For syncope patients, we must first obtain three aspects of information-medical history, physical examination, conventional 12-lead ECG. A detailed medical history and physical examination provide directions for the diagnosis of syncope. An electrocardiogram can help rule out many cardiogenic diseases, and then conduct targeted inspections to try to determine the cause of syncope. A typical history and physical examination can make a diagnosis of vasovagal syncope. However, for high-risk patients without prodromal symptoms and susceptible to trauma, cardiac ultrasound and
- The treatment of vasovagal syncope is mainly based on publicity and education. Encourage patients to increase water and sodium intake and avoid triggers as much as possible. When prodromal symptoms occur, lie down immediately, flex arms and calves to avoid trauma. If the patient wants, you can try standing training, first stand against the wall for 5 minutes every day, and gradually increase to 15-30 minutes. Patients at high risk who are prone to injury without prodromal symptoms should take preventive medication. It is recommended to take methamphetamine first, 5 mg per day, 3 times a day, and if it still occurs, it can be increased to 10 mg per day. If the symptoms are not relieved but can not be completely controlled, you can add fludrocortisone, 0.1 mg per day, or take a selective serotonin reuptake inhibitor. If the patient does not show symptoms for 1 year, the drug can be gradually reduced until discontinuation, but if the symptoms recur, the medication needs to be restarted.
- In general, the prognosis of patients with vasovagal syncope is better, but for the elderly, due to the high risk of syncope, more attention should be paid.