Fainting (syncope) is the partial or complete loss of consciousness with interruption of awareness of oneself and ones surroundings. When the loss of consciousness is temporary and there is spontaneous recovery, it is referred to as syncope or, in nonmedical terms, fainting. Syncope accounts for one in every 30 visits to an emergency room. It is pronounced sin-ko-pea.
Syncope is due to a temporary reduction in blood flow and therefore a shortage of oxygen to the brain. This leads to lightheadedness or a "black out" episode, a loss of consciousness. Temporary impairment of the blood supply to the brain can be caused by heart conditions and by conditions that do not directly involve the heart.
Other causes of fainting
Non-heart Causes: Syncope is most commonly caused by conditions that do not directly involve the heart. These conditions include the following:
- Postural (orthostatic) hypotension: drop in blood pressure due to changing body position to a more vertical position after lying or sitting
- Diseases of the nerves to the legs in older people (especially with diabetes or Parkinson's disease) when poor tone of the nerves of the legs draws blood into the legs from the brain
- High altitude
- Fainting after certain situations (situational syncope) such as
- blood drawing,
- urinating (micturition syncope),
- defecating (defecation syncope),
- swallowing (swallowing syncope),
- coughing (cough syncope) that trigger a reflex of the involuntary nervous system (the vasovagal reaction) that slows the heart and dilates blood vessels in the legs and cause one to feel nausea, sweating, or weakness just before fainting.
Heart Causes: Heart conditions that can cause syncope or fainting due to temporary loss of consciousness include:
- Abnormal heart rhythms (heart beating too fast or too slow)
- Abnormalities of the heart valves (pulmonic valve stenosis)
- Widespread disease of the heart muscle (cardiomyopathy)
Medications can cause fainting by altering blood pressure or by affecting the heart.Next Article
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Causes of Fainting
Anaphylaxis is a serious allergic reaction that affects a number of different areas of the body at one time, and can be fatal. Causes of anaphylaxis can be food allergy, latex allergy, allergy to insect or but stings/bites, asthma, or other materials or conditions. Symptoms include flushing, itching, hives, anxiety, rapid or irregular pulse. Severe symptoms may be throat and tongue swelling, swallowing, and difficulty breathing. Some disorders appear similar to anaphylaxis such as fainting, panic attacks, blood clots in the lungs, heart attacks, and septic shock. If you think that you may be having an anaphylactic reaction, seek emergency care or call 911 immediately.
Anemia: Symptoms, Treatment and Causes
Anemia is the condition of having less than the normal number of red blood cells or less than the normal quantity of hemoglobin in the blood. The oxygen-carrying capacity of the blood is, therefore, decreased. There are several types of anemia such as iron deficiency anemia (the most common type), sickle cell anemia, vitamin B12 anemia, pernicious anemia, and aplastic anemia. Symptoms of anemia may include fatigue, malaise, hair loss, palpitations, menstruation, and medications. Treatment for anemia includes treating the underlying cause for the condition. Iron supplements, vitamin B12 injections, and certain medications may also be necessary.
Aortic Valve Stenosis (Symptoms, Causes, Surgery)
Aortic valve stenosis is an abnormal narrowing of the aortic valve of the heart. The causes of aortic stenosis are wear and tear of the valve in the elderly, congenital, or scarring or scarring of the aortic valve from rheumatic fever. Symptoms include angina, fainting, and shortness of breath. Treatment is dependant upon the severity of the condition.
Atrial Fibrillation (AFib) Symptoms and Signs
Atrial fibrillation or AFib is a type of heart rhythm abnormality. Early warning signs and symptoms of atrial fibrillation include chest pain, palpitations, shortness of breath, and lightheadedness. Treatment for atrial fibrillation includes medical procedures, surgery, and medication.
Atrial Fibrillation (AFib) Treatment Drugs
Atrial fibrillation (AFib) is a heart rhythm disorder that causes irregular and often rapid heartbeat. The medications to treat AFib include beta-blockers, blood thinners, and heart rhythm drugs. Atrial fibrillation drugs can cause serious side effects like seizures, vision changes, shortness of breath, fainting, other abnormal heart rhythms, excessive bleeding while coughing or vomiting, blood in the stool, and bleeding into the brain.
Atrial Flutter vs. Atrial Fibrillation
Atrial flutter and atrial fibrillation (AFib) are two types of a heart problem called atrial tachycardia. Both of these conditions involve the heart's electrical activity, but they are not the same disease. Both diseases are serious and need medical treatment. Common symptoms of these diseases are similar and include: Fatigue Blurry vision Lightheadedness Palpitations Feeling like you may faint Serious symptoms of both conditions are similar and include: Fainting Sweating Severe shortness of breath Chest pain Atrial flutter and AFib are heart conditions that require medical diagnosis (ECG) and treatment by a doctor or other medical health-care professional.
Dilated Cardiomyopathy is a condition where the heart's ability to pump blood is decreased because the heart's main pumping chamber is enlarged and weakened. Symptoms of dilated cardiomyopathy include chest pain, heart failure, swelling of the lower extremities, fatigue, weight gain, fainting, palpitations, dizziness and blood clots.
Hypertrophic cardiomyopathy (HCM) affects many people today. Many people with HCM have no symptoms or only minor symptoms, and live a normal life. Other people develop symptoms, which progress and worsen as heart function worsens.
Restrictive cardiomyopathy, the rarest form of cardiomyopathy, is a condition in which the walls of the lower chambers of the heart (the ventricles) are abnormally rigid and lack the flexibility to expand as the ventricles fill with blood. The pumping or systolic function of the ventricle may be normal but the diastolic function (the ability of the heart to fill with blood) is abnormal. Therefore, it is harder for the ventricles to fill with blood, and with time, the heart loses the ability to pump blood properly, leading to heart failure.
Chagas Disease (American Trypanosomiasis or Kissing Bug Disease)
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Dehydration is the excessive loss of body water. There are a number of causes of dehydration including heat exposure, prolonged vigorous exercise, and some diseases of the gastrointestinal tract. Symptoms of dehydration include headache, lightheadedness, constipation, and bad breath. Treatment for dehydration is to replace lost fluids and electrolytes.
Diabetes (Type 1 and Type 2)
Diabetes is a chronic condition characterized by high levels of sugar (glucose) in the blood. The two types of diabetes are referred to as type 1 (insulin dependent) and type 2 (non-insulin dependent). Symptoms of diabetes include increased urine output, thirst, hunger, and fatigue. Treatment of diabetes depends on the type.
Early Pregnancy Symptoms and Signs
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Heart Attack Treatment
A heart attack involves damage or death of part of the heart muscle due to a blood clot. The aim of heart attack treatment is to prevent or stop this damage to the heart muscle. Heart attack treatments included medications, procedures, and surgeries to protect the heart muscle against injury.
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Insect Sting Allergies
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Is POTS a Serious Condition?
Postural orthostatic tachycardia syndrome (POTS) is a syndrome characterized by increased heart rate (tachycardia), a fall in blood pressure (hypotension) and giddiness when standing (orthostatic). In POTS, the symptoms occur because the heart does not receive sufficient blood supply when the person stands upright.
Low Blood Pressure (Hypotension)
Low blood pressure, also referred to as hypotension, is blood pressure that is so low that it causes symptoms or signs due to the low flow of blood through the arteries and veins. Some of the symptoms of low blood pressure include light-headedness, dizziness, and fainting if not enough blood is getting to the brain. Diseases and medications can also cause low blood pressure. When the flow of blood is too low to deliver enough oxygen and nutrients to vital organs such as the brain, heart, and kidneys; the organs do not function normally and may be permanently damaged.
Migraine headache is a type of headache associated with a sensitivity to light, smells, or sounds, eye pain, severe pounding on one side of the head, and sometimes nausea and vomiting. The exact cause of migraine headaches is not known. Triggers for migraine headaches include certain foods, stress, hormonal changes, strong stimuli (loud noises), and oversleeping. Treatment guidelines for migraines include medicine, pain management, diet changes, avoiding foods that trigger migraines, staying hydrated, getting adequate sleep, and exercising regularly. Prevention of migraine triggers include getting regular exercise, drinking water daily, reducing stress, and avoiding trigger foods.
Palpitations are uncomfortable sensations of the heart beating hard, rapidly, or irregularly. Some types of palpitations are benign, while others are more serious. Palpitations are diagnosed by taking the patient history and by performing an EKG or heart monitoring along with blood tests. An electrophysiology study may also be performed. Treatment of palpitations may include lifestyle changes, medication, ablation, or implantation of a pacemaker. The prognosis if palpitations depends on the underlying cause.
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POTS (POT Syndrome, Postural Orthostatic Tachycardia Syndrome)
POT syndrome (POTS, postrual orthostatic tachycardia syndrome) is a nervous system disorder that causes lightheadedness and fainting when a person stands up. Treatment may include increasing blood volume and regulating circulatory problems that are responsible for the disorder.
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What Are the Symptoms of Dysautonomia?
Dysautonomia is also called autonomic dysfunction or autonomic neuropathy. The symptoms of dysautonomia include fainting, dizziness, balance problems, brain fog, chest pain, palpitations, trouble swallowing, sleep problems and other issues.
What Is Aortic Dissection?
Aortic dissection is a small tear in the large blood vessel that leads from the heart and supplies blood to the body. Symptoms of aortic dissection include a tearing or ripping pain, nausea, sweating, weakness, shortness of breath, sweating, or fainting. Treatment depends on the type of aortic dissection, and the severity of the tear in the aorta.
Brain and Nervous System Resources
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