"This suggests that acupuncture can be an excellent complement to other medical treatments," said Dr Longhurst, the study's lead researcher. "Especially for those treating the cardiac system."

These studies suggest that acupuncture triggers the release of chemicals in the brain that dampen the response of the cardiovascular system. This decreases the heart's activity and need for oxygen, which as a result could lower blood pressure. Therefore, acupuncture could promote healing for a number of heart conditions including heart attacks and hypertension.

Electroacupuncture, like that used in the study, is small, low frequency electrical currents that are passed through normal acupuncture needles. The same points are stimulated as with traditional acupuncture. Needles are inserted on specific points along the body and then attached to a device that generates continuous, small electric pulses. The device adjusts the frequency and intensity of the impulse being delivered, depending on the condition being treated. Electroacupuncture employs two needles at once so that the impulses can pass from one needle to the other. Several pairs of needles can be stimulated simultaneously, usually for no more than 30 minutes at a time.