Adams-Stokes syndrome is a heart condition that causes brief episodes of fainting. It can often be treated with the use of a pacemaker.
Adams-Stokes syndrome is a heart condition. People with this condition experience periodic bouts of fainting (syncope) with no apparent trigger. This condition is also referred to as Stokes-Adams syndrome and as Stokes-Adams attacks.
This article will cover the causes, symptoms, and known risk factors for Adams-Stokes syndrome. We’ll also discuss how it’s diagnosed and treated.

Fainting is the main symptom of Adams-Stokes syndrome. Fainting may occur without warning and in any position, like sitting, standing, or walking.
Fainting, or passing out, is medically referred to as syncope. People with Adams-Stokes syndrome faint briefly, for seconds at a time. They typically regain consciousness abruptly and experience confusion or disorientation upon awakening. Flushed, red skin is common upon awakening.
Additional symptoms may start minutes or hours prior to fainting. These vary from person to person but can include:
- irregular pulse
- arrhythmia (erratic or slow heartbeat)
- involuntary twitching
- pale or sweaty skin
- feeling lightheaded or dizzy
Some people may also experience seizure-like convulsions. Because of this, Adams-Stokes
The fainting episodes caused by Adams-Stokes syndrome occur when your heart rate abruptly speeds up or slows down. These changes alter blood flow to the brain, causing a fainting episode to occur.
People with Adams-Stokes syndrome typically have a complete third-degree heart block (atrioventricular block). This blockage disrupts electrical signals that control heart rate, causing a slowing of the heart rate.
Your heart rate, or pulse, refers to the number of times your heart beats per minute. A normal heart rate in adults ranges anywhere from 60 to 100 beats per minute.
When a heart is functioning normally, electrical impulses, or signals, travel unhampered from the atria (upper chambers of the heart) to the ventricles (lower chambers of the heart). These signals tell the ventricles to pump blood to the brain, lungs, and body.
If you have a heart block, communication between the atria and ventricles becomes disrupted and erratic, altering blood flow to the brain.
Having a complete (third-degree) heart block is the most significant risk factor for Adams-Stokes syndrome. Complete heart blocks can also be caused by coronary heart disease, with or without heart attacks.
Having a disease that weakens the heart muscle or causes heart inflammation
Other risk factors may include:
- sarcoidosis
- Lyme disease
- some cancers and cancer treatments
- severe hyperthyroidism
- cardiomyopathy
- congenital heart disease
- electrolyte abnormalities
It’s also possible to be born with a heart block. This is known as congenital heart block.
It’s important to see a healthcare professional for diagnosis and treatment if you’re fainting without warning.
Your healthcare professional will diagnose your condition by giving you a complete physical and by asking you about your symptoms. During your physical, they’ll check blood pressure and may also do a blood test to check your cholesterol levels and blood markers for disease.
To rule out medication side effects, they’ll ask about the prescription and nonprescription drugs and supplements you take.
You’ll also be given an electrocardiogram (EKG), which records the heart’s electrical impulses. If the EKG results are inconclusive, your doctor will likely follow up with additional tests to monitor your heart, like:
- heart ultrasound (echocardiogram) to view your heart and heart valves
- exercise stress test to measure heart response during exertion
- 24-hour Holter monitoring to measure heart rate and rhythm for 12 to 48 hours
Treatment for Adams-Stokes syndrome requires treating the underlying third-degree heart block that causes this condition. This typically requires the surgical implantation of a pacemaker. Pacemakers are small electrical devices that stabilize heart rate.
Treating Adams-Stokes syndrome reduces your risk of complications, like cardiac arrest. It also eliminates or reduces fainting episodes that may cause serious falls and accidents, like those that might occur while driving or operating machinery.
If you’re living with a pacemaker, it’s important to regularly meet with your healthcare professional for checkups and routine pacemaker checks.
Adams-Stokes syndrome is a condition that causes brief episodes of fainting. It’s typically caused by having a third-degree heart block.
Treatment for Adams-Stokes centers upon treating the underlying heart block. The most common treatment is the surgical implantation of a pacemaker.
The outlook for people who receive treatment is very good. It’s important to follow your healthcare professional’s instructions for living with a pacemaker and to receive follow-up treatments if needed.