Blackouts or fainting, are known in medical jargon as syncope. It is a transient loss of consciousness resulting from decreased blood flow to the brain. While various factors can cause a blackout, heart-related issues need to be considered. Understanding the heart origins of syncope involves considering conditions such as arrhythmias, structural heart diseases, and vasovagal syncope.

Arrhythmias , abnormal heart beats, are a leading cardiac cause of syncope. Conditions like slow heart beat (bradycardia) or fast heart beat (tachycardia), particularly if they result in significant changes in blood flow, can lead to syncope. Abnormal heart beats are described in more details in the `arrhythmia section`.

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