Pacemakers Prevent One Form of Fainting - Vasovagal Syncope

The vasovagal syncope is one of the more common and potentially serious causes of fainting. The condition develops when an inappropriate reflex in the nervous system leads to opening (dilation) of the blood vessels along with slowing of the heart rate (bradycardia).

With slowing of the heart rate and dilation of the blood vessels in the legs, the blood pressure is lowered. Because blood is directed to the legs, less blood (and therefore less oxygen) goes to the brain. Fainting (syncope) is the outcome, which can be troublesome as well as dangerous.

Pacemakers can be used in persons with serious slowing of the heart rate (bradycardia) to maintain a normal heart rate.

The first randomized controlled study of pacemakers in the prevention of vasovagal syncope has now been published in the current issue of the Journal of the American College of Cardiology (1999;33:16-20). This eagerly anticipated trial was performed by multiple medical centers throughout the United States and Canada in a collaborative effort called The North American Vasovagal Pacemaker Study.