What is fainting caused by cardiac conditions?

Fainting is a temporary loss of consciousness that may occur when not enough blood reaches the brain. Certain heart conditions may cause you to faint.

The medical term for fainting is syncope.

How does it occur?

Any heart condition that causes your heart to pump less blood to your brain can cause fainting. Your heart may not be able to pump enough blood to your brain if you have:

• a heart rate that is too slow

• a heart rate that is too fast

• heart valve problems.

What symptoms may occur before fainting?

Symptoms that may occur before you faint include:

• heart palpitations (feeling and hearing your heart pound)

• feeling lightheaded

• dizziness

• nausea

• weakness.

How is it diagnosed?

Anyone who faints for the first time should see a doctor to find out why. To determine the cause of fainting, the doctor will take your medical history and examine you. He or she will take your blood pressure and pulse.

Depending on your medical history and physical exam, your doctor may order lab tests and an electrocardiogram (ECG). An ECG is a recording of electrical impulses from the heart. If there is a possible abnormal heart valve, your doctor may order an echocardiogram (an ultrasound scan of your heart).

How is it treated?

Your doctor may prescribe medicines to help control your heart rate. If your heart sometimes beats too slowly and causes fainting, you may need a pacemaker. This device uses electrical impulses to correct the heart rate.

What should I do after fainting?

After you faint, you will return to consciousness when normal blood flow to your brain returns. You should lie down for 10 to 15 minutes after you return to consciousness. If there is no one to help you after you have rested, try sitting. If you have no more symptoms while you are sitting and your pulse feels normal, contact your doctor according to his or her instructions.

How can I take care of myself?

Follow the full treatment recommended by your doctor.

First aid for fainting:

• If you feel faint, lie down if possible and put your feet up. If you can't lie down, sit down and lean forward with your head between your knees.

• If someone has already fainted but has a good pulse and is breathing normally, raise the person's legs above the level of his or her chest. This returns more blood to the brain and will probably return the person to consciousness.

• If a person has already fainted and has no pulse or isn't breathing, call 911. If you know how, begin CPR. Call 911 if a person faints and remains unconscious for more than 2 minutes.

How can I prevent fainting caused by cardiac conditions?

• Avoid sudden changes in your position.

• Avoid strenuous physical activities.

• If you continue to have fainting episodes, tell your doctor.