• Texas Medical Center, 6560 Fannin St. #1680, Houston, TX 77030
  • Heights Office, 427 W 20th St Houston, TX 77008
  • Texas Medical Center, 6560 Fannin St. #1680, Houston, TX 77030
  • Heights Office, 427 W 20th St Houston, TX 77008


What is Syncope?

Syncope (pronounced sin-ko-pee), also known as fainting, passing out, or blacking out, is a transient state of loss of consciousness, alertness, and muscle strength that occurs because of a decrease in blood flow to the brain. Episodes happen quickly but do not last long, and those affected usually regain complete alertness within a few minutes.

The causes of syncope range from benign conditions to life-threatening ones, such as abnormal heart rhythms (arrhythmias). Individuals who experience syncope may have other symptoms, including nausea, sweating, palpitations, chest pain, shortness of breath, and lightheadedness, before they totally lose consciousness.

Some people may feel nauseous, dizzy, and lightheaded, and may get the sensation that they are going to pass out, but do not lose consciousness. This state is called near syncope, or almost fainting, and should be taken just as seriously as syncope.

Because syncope involves a temporary loss of alertness and muscle strength, episodes may lead to injuries if they occur while you are driving a vehicle, operating heavy machinery, or working up on a ladder.

If you are 65 years of age or older, syncope can cause frequent falls, leading to serious injuries such as broken hips or life-threatening blows to the head. If you experience frequent falls, it is essential to see a doctor to find out if they are a result of syncope.

Syncope episodes that occur during exercise, are associated with chest pain or palpitations, or occur in a person with a family history of sudden cardiac death may suggest the presence of a severe heart abnormality.

It is crucial to identify the cause of syncope and prevent additional episodes. If you have experienced syncope, you should be evaluated by a physician. To schedule an evaluation with Dr. Alireza Nazeri in Houston, Texas, call (713) 909-3166.

Types of Syncope

Vasovagal Syncope

Vasovagal syncope (VVS) is the most common form of fainting and a frequent reason for visits to the emergency department. This type is also called reflex, neurocardiogenic, neurally mediated, or vasodepressor syncope. It is benign and rarely requires medical treatment.

Vasovagal syncope can occur at any age, but is more common in children and young adults. Episodes occur when an area of the nervous system that regulates blood pressure and heart rate does not respond effectively to a trigger, such as emotional stress or pain.

Vasovagal syncope usually occurs while the individual is standing. Before passing out, those affected usually experience symptoms such as a sensation of warmth, flushing, nausea, lightheadedness, tunnel vision, or visual “grayout.”

Situational syncope, which is a type of vasovagal syncope, occurs in connection with specific physical functions, such as violent coughing (primarily in men), laughing, swallowing, or urinating.

Cardiac Syncope

Heart and vascular diseases can interrupt the normal blood flow to the brain, depriving it of oxygen and causing fainting. This is called cardiac syncope. Syncope episodes that occur with exercise, are associated with chest pain or palpitations, or occur in a person with a family history of sudden cardiac death may suggest the presence of a severe heart abnormality.

Some of the heart-related conditions that can cause syncope include bradycardia (abnormally slow heartbeat)tachycardia (fast, irregular heartbeat), low blood pressure, heart attack, heart failure, abnormal heart valve function, and blood clots in the major lung arteries (pulmonary embolism).

These conditions can increase the risk for sudden cardiac death (which occurs when the heart suddenly stops working). Disorders like heart failure and atrial fibrillation can cause frequent episodes of syncope in older adults, especially after the age of 70.

If you experience near-fainting or fainting spells, visit your doctor to rule out serious heart conditions.

Syncope can also occur as a side effect of certain medicines. For instance, loss of consciousness can result from a sudden drop in blood pressure caused by blood pressure medications or from a decrease in blood sugar levels in patients who take insulin or other antidiabetic medications.

Other Causes of Fainting

There are other conditions, such as seizure disorders, that can cause loss of consciousness and have a similar presentation to vasovagal or cardiac syncope.

Syncope Testing

During the initial evaluation, your doctor will ask a series of questions to obtain detailed information about the fainting episodes you have experienced, as well as your relevant medical history. You will then undergo a thorough physical examination and measurements of your blood pressure and heart rate.

Prepare for your doctor’s appointment:

  • Write down what happens before, during, and after a fainting episode, including any symptoms you may experience.
  • Prepare an up-to-date list of your medications before your visit. You can also bring your medications to your doctor’s office. Some of the medicines you may be taking may increase the risk for syncope when taken alone or in combination with other substances.
  • Tell your doctor about any over-the-counter medications, weight loss supplements, or other herbal supplements you are taking.
  • Ask a family member or a friend who has witnessed your blackout(s) or fall(s) to go with you to the appointment. If they cannot accompany you, ask them to write down exactly what they saw, or ask them how the doctor can contact them if necessary.
  • It is important to find out if you have a family history of blackouts, epilepsy, or sudden/unexplained death. This can often provide a clue as to the possible cause of your fainting episodes.
  • Write down the questions you want to ask your doctor or the specialist you will see, because it can be easy to forget some of them during the consultation.

After obtaining a detailed history and performing a physical examination, your doctor may recommend one of the following tests, or a combination of them, to try to identify the cause of your syncope:

  • Orthostatic blood pressure measurement. Your blood pressure and heart rate will be measured while lying down and immediately after standing up. If your blood pressure drops or you feel dizzy after you rise up to a standing position, this may be a sign of dehydration, or could suggest an underlying heart or vascular disease.
  • Electrocardiogram (EKG or ECG). A recording of your heart’s electrical activity is typically part of the initial evaluation performed to identify the cause of syncope.
  • Blood tests. Your blood will be tested to check for anemia, an imbalance in the electrolytes (e.g., sodium, potassium, magnesium), kidney dysfunction, and thyroid dysfunction.
  • Echocardiogram or stress test. These tests may be necessary to assess your heart function.
  • Heart rhythm monitoring. Your doctor may recommend a wearable cardiac monitor or an implantable loop recorder to monitor your heart rhythm. This will help the physician determine if certain heart rhythm abnormalities are the cause of your syncope.
  • Tilt-table testing. This test could also be used to look for the cause of your syncope.
  • Referrals. Your doctor may refer you to a neurologist, who can investigate whether your loss of consciousness is caused by a seizure disorder.

Treatment for Syncope in Houston, TX

The treatment of syncope is designed to manage or treat the underlying conditions that are causing the loss of consciousness. Your doctor will explain the cause or causes of your fainting episodes and will recommend a treatment plan that is right for you.

If you are diagnosed with vasovagal syncope or situational syncope, you may benefit from:

  • Lifestyle modifications to avoid specific triggers that cause your episodes
  • Increased hydration with electrolyte-rich fluids
  • Wearing compression stockings
  • Exercise
  • Increased salt intake
  • If your blood pressure is persistently low, you may benefit from certain medications that can keep your blood pressure from dropping and may help prevent future fainting episodes.

If the cause of your syncope is heart-related, your doctor may recommend a treatment plan that can include a pacemaker, an implantable cardioverter defibrillator (ICD), an electrophysiology study, or catheter ablation to correct your abnormal heart rhythm (arrhythmia).

Living with Syncope

Being likely to faint can be stressful and can make you feel anxious in public places, including the workplace.

Fortunately, future episodes can become less frequent or can even be prevented if you find a doctor who can diagnose your condition correctly, identify its cause, and work with you to develop an individualized treatment plan.

Here are a few key points to consider when you seek help in managing your fainting episodes:

  1. Find a healthcare professional who specializes in syncope. If you need a referral, your primary care doctor can help you find physicians who specialize in diagnosing and managing this condition, such as electrophysiologists (EPs) and neurologists.
  2. Learn to identify and avoid syncope triggers.
  3. Ask your doctor when you can resume driving after receiving treatment.
  4. Learn about optimal ways to rise from a seated or lying position.
  5. Learn about proper fluid intake, including the minerals you need in your water.
  6. Compression stockings can prevent fluid from pooling in the legs and support a healthy blood flow. Ask your doctor how compression stockings can help with syncope and which type you should wear (e.g., low, medium, or high-pressure).
  7. Avoid drinking alcohol.
  8. Drink coffee or tea in moderation. Tell your doctor if you drink herbal teas, because some can lower your blood pressure or stimulate your heart, which can cause syncope.
  9. Exercise regularly. Team up with your doctor to develop an exercise plan that is suitable and safe for you.
  10. Monitor your blood pressure at home and keep a blood pressure record that you can review regularly with your doctor.
  11. Consider increasing your salt intake.
  12. Be aware of the symptoms you experience before fainting. Common symptoms and signs include lightheadedness, nausea, and cold, clammy skin. If you experience these symptoms or signs, you can use one of the following strategies, or a combination of these, to avoid fainting:
    • Sit down or lie down immediately and elevate your legs.
    • Handgrip. Hold a rubber ball in your hand and squeeze it continuously for as long as you can.
    • Arm-tensing. Grasp one hand tightly with the other and pull them against each other without letting go.
    • Leg-crossing. Cross one leg over the other and squeeze the muscles in your abdomen, buttocks, and thighs.
    • Continue the chosen maneuver(s) until your symptoms disappear.

For Comprehensive Heart Disease Care Contact Dr. Alizera Nazeri

If you have heart disease or have known risk factors, call Dr. Alizera Nazeri at (713) 909-3166 to schedule an evaluation or Request an Appointment online. He sees patients in Houston, Texas.

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