Can fainting spells be life-threatening?

Can fainting spells be life-threatening?

Fainting occurs because of insufficient blood flow to the brain and is almost always due to a cardiac cause, warns Dr Jayaprakash Shenthar


Fainting is a temporary loss of consciousness (TLOC) that results in a fall if a person is upright, and is referred to as syncope in medical terms. The onset of syncope occurs suddenly, may or may not be associated with warning signs, the duration is usually brief, lasting a few seconds to a few minutes. The warning signs before an attack of fainting may be in the form of sweating, feeling of weakness, a blackout, butterflies in the stomach, palpitations in the chest, and at times, can happen even without a warning. Fainting occurs because of insufficient blood flow to the brain and is almost always due to a cardiac cause.

Fainting/syncope is quite common and it is estimated that it occurs in 15-25% of the general population. Fainting is often recurrent, may lead to poor quality of life, result in injuries, and in some patients may point to underlying severe heart disease. Fainting can occur both in patients with a healthy heart as well as those with a heart disease. People who have an underlying heart disease, especially those with a weak heart (low ejection fraction), are at an increased risk of fainting/syncope. Fainting may be the only warning sign of abnormal heart rhythm (arrhythmia). Rapid heartbeats such as ventricular tachycardia or ventricular fibrillation or slow heartbeats that result in the temporary stopping of the heart for a few seconds causing a temporary cessation of blood flow to the brain can result in fainting/syncope. Another common cause of faint/syncope is the sudden and brief fall in blood pressure in upright position causing a decreased blood supply to the brain.

Fainting is caused by a variety of cardiac conditions, and hence the treatment is varied. The diagnostic evaluation of someone fainting is based on the history, thorough physical examination, electrocardiogram (ECG), long-term rhythm monitoring to correlate the symptoms with the ECG abnormality and specific tests to evaluate the electrical conduction system. Syncope should not be ignored as no episode of loss of consciousness is normal. While the causes of fainting are commonly believed to be neurological, the real reason is usually cardiac in nature. Therefore, one must visit a cardiac electrophysiologist, or a heart rhythm expert for diagnosis.

(The author is consultant electrophysiologist)