Getting to the heart of a fainting spell

Fainting happens when the brain isn’t getting enough blood, which leads to a temporary loss of consciousness. Most of the time, fainting is benign and not the symptom of a serious underlying problem. In people who are otherwise healthy, fainting (what doctors call syncope) is rarely the first manifestation of a cardiovascular problem. However, people who already have heart problems are more prone to fainting than the average person.