- Cardiogenic syncope - causes
- Syncope - cerebrovascular changes
- Neurocardiogenic (vasovagal) syncope - causes
- Faintingorthostatic - causes
- Syncope - hyperventilation
- Fainting - pregnancy
- Fainting - mental illness
Syncope is a symptom of various causes. Fainting can be an emotional reaction, such as severe pain or the sight of blood. Then there is no need for concern. Unfortunately, the experience of doctors has shown that a temporary loss of consciousness usually indicates serious he alth problems, especially if it occurs in people who are struggling with heart disease. Find out what causes fainting.
Faintingis a sudden, short-term loss of consciousnessloss of consciousnesswith loss of postural tension and subsequent spontaneous recovery. Postural tension is the muscle tension that allows you to withstand the force of gravity without difficulty, and its loss causes you to fall when you faint.
Fainting occurs when the oxygen supply to the brain is reduced for a short time. Temporary hypoxia of this organ is a consequence of insufficient blood flow, which in turn depends on the proper work of the heart, a sufficient volume of circulating blood and its adequate flow in the vessels. Impairment of any of these mechanisms could cause fainting.
Cardiogenic syncope - causes
1. Obstruction of the outflow of blood from the heart and filling the heart with blood
- valvular disease: a rough murmur, with a late apex at the base of the heart, radiating into the carotid arteries, suggesting aortic stenosis. Other valvular diseases that cause exercise syncope are mitral stenosis, Fallott's tetralogy, and artificial valve dehiscence. Above the symptoms may also be the result of a malfunction of the artificial valve.
- Hypertrophic cardiomopathy, restrictive myopathy, tamponade, and rupture of the heart muscle usually produce symptoms such as a systolic murmur that increases with the Valsava trial and disappears when squatting
- common syncope due to major embolism, combined with shortness of breath, tachycardia and tachycardia, indicates pulmonary embolism, amniotic fluid embolism or, rarely, air embolism.
- a click and murmur heard early during contraction and more clearly in an upright position may indicate mitral leaflet prolapse
- heart tumors or blood clots
2. Cardiac arrhythmias
An abnormal heart rhythm causes you to faint when the heart rate is too fast,to ensure sufficient ventricular inflation (tachycardia e.g.>150-180 bpm), or too slow to ensure sufficient throw (bradycardia, <30-35 bpm) .
Bradycardia often occurs in elderly people and may be caused by sick sinus syndrome or high-degree AV block. Low heart rate may also be a consequence of taking certain medications (including beta-blockers, calcium channel blockers or dioxins)
In turn, tachycardia, or tachycardia, may indicate ischemia, heart failure and diseases of the heart muscle. Electrolyte disturbances (e.g. in the course of anemia) can also contribute to tachycardia. Among the drugs that cause the heart rate to accelerate, there are i.a. antiarrhythmic drugs and quinidine.
3. Ventricular dysfunction
Ventricular dysfunctions, such as recent myocardial infarction, myocarditis, systolic or diastolic dysfunction, and cardiomopathy, rarely present with syncope. However, if they do occur, it is much more common in elderly people with cardiac arrhythmias.
Syncope - cerebrovascular changes
Cerebrovascular changes, such as transient ischemic attacks in the postural artery or stroke, may cause unconsciousness. It is then that ataxia appears, i.e. a set of symptoms that identify disturbances in the body's motor coordination.
A migraine may also be a cause of fainting, indicated by an aura with ocular symptoms and photophobia.
Neurocardiogenic (vasovagal) syncope - causes
The most common form of syncope is vasovagal syncope, resulting from the dysfunction of the vegetative nervous system, which corresponds, inter alia, to for regulating blood pressure and heart rate.
There are two types of vasovagal syncope: peripheral and central. Peripheral syncope is caused by prolonged standing still. In turn, in the central, emotional type, fainting occurs immediately after the unpleasant physical stimulus (e.g. stressful situation, severe pain, fear, sight of blood) is triggered. The immediate cause of syncope in each case is the person's hypotension and bradycardia.
Another cause of neurocardiogenic syncope may be an increase in pressure in the chest, which can be caused by a pressure pneumothorax, coughing, sneezing, straining to urinate or defecate. The consequence may be inhibition of venous return to the right atrium (by pressure on the vein that transports blood to the heart) and fainting.
Faintingorthostatic - causes
Orthostatic hypotension, i.e. a drop in blood pressure, is one of the rare causes of syncope. These syncope is usually caused by a sudden change of position from lying to standing or standing for a long time without moving. However, if they are preceded by chronic fatigue, sometimes dark stools, and heavy periods, these may indicate anemia. Also, taking medications (e.g. antihypertensive drugs, antipsychotics, levodopa, loop diuretics and vincristine) may cause orthostatic syncope.
Syncope - hyperventilation
Hyperventilation, or breathing too quickly, leads to metabolic disorders such as tingling around the mouth or fingers, numbness, cramping of the lips, face, hands and feet, and then fainting. Hyperventilation is often associated with a strong emotional experience or anxiety.
Fainting - hypovolemia
Fainting may be caused by insufficient circulating blood volume due to dehydration or hemorrhage. The amount of blood circulating in the vessels due to bleeding or extracellular fluids may be too low to provide oxygen to all organs, including the brain.
Fainting - pregnancy
Fainting of a he althy woman of childbearing age who has no other complaints usually indicates an early or unrecognized pregnancy. Fainting is then a consequence of a drop in blood pressure, which is quite common in the first months of pregnancy.
On the other hand, women in the last trimester of pregnancy may struggle with fainting while lying on their backs. Then, the loss of consciousness is a result of uterine pressure on the inferior vena cava, which results in impeding the return of blood from the vessels to the heart.
Fainting - mental illness
If the patient reacts partially or inadequately to a faint, this indicates pseudo fainting.