What Heart Condition Causes Seizures?

Many people who have seizures are diagnosed with epilepsy. However, when further testing is performed, doctors find that some of these individuals actually have cardiovascular syncope--a condition resulting from irregular heart rhythms and blood flow. Cardiac syncope is characterized by a "fainting spell" or loss of consciousness.

Is This an Emergency?

If you are experiencing serious medical symptoms, seek emergency treatment immediately.

Disrupted Heart Rhythm

Cardiac arrhythmia is the term given to an irregular heartbeat. According to the American College of Cardiology, arrhythmia may occur in five different forms: premature beats, atrial fibrillation, bradycardia, tachycardia and ventricular arrhythmias. Premature beats usually are not dangerous and can be induced by factors such as stress and caffeine. Atrial fibrillation is an electrical disorder in which two valves of the heart do not pump out blood properly, causing the blood to pool and sometimes clot. Bradycardia is a reduction in the speed of the heart's beat, which may cause dizziness, fainting and fatigue. Tachycardia is a heartbeat that is too fast, which can cause problems in blood flow. Ventricular arrhythmias are the most deadly form of arrhythmia and occur when the ventricles of the heart do not pump blood properly. Out of these five major categories, atrial fibrillation, bradycardia and ventricular arrhythmias can cause "syncope" or fainting.

Syncope vs. Seizures

Some seizures appear to be similar to the fainting spells experienced in cardiac syncope, as they also involve a loss of consciousness 1. There are several common differences, however. If you experience syncope, you will usually regain consciousness more quickly than if you had experienced a seizure. With a seizure, you are more likely to urinate; you also may have a headache, sleepiness and disorientation afterward 1. Seizures seem to temporarily suspend protective reflexes, thereby resulting in a greater likelihood of fall and injury. Cardiac syncope does not suspend these reflexes. An occasional symptom of both syncope and seizures is jerking, which makes a definitive diagnosis harder to make. The only way to positively distinguish between the two is through further medical testing.


To diagnose potential cardiac syncope, a physician will investigate personal and family history. After this initial inquiry, medical tests may include electrocardiogram (ECG), tilt table, various recorders that monitor heart activity, carotid sinus massage and electrophysiology study (EPS). These tests allow doctors to check for physical and/or electrical abnormalities in the heart and observe how the heart reacts to changes in blood pressure, activity and electrical stimulation.


Once doctors determine which type of heart malfunction is causing the cardiac syncope, he will prescribe a treatment that fits that particular problem. Treatments include the use of a pacemaker or defibrillator if the heart is beating at the wrong pace. Cardiac ablation is an option for the treatment of electrical problems in the heart. At times, the use of medication without further invasive procedures may control the problem.

Managing a Seizure or Syncope

If you observe someone having what appears to be a seizure or fainting spell, position the person on her side 1. Do not try to restrain the person or put your hand in the patient's mouth. Remove any objects from the area that could be dangerous. Make sure airways are cleared and the person can breathe freely. If the seizure or fainting spell lasts longer than five minutes, call an ambulance 1.