A heart condition present at birth in which an extra heart signaling pathway causes a rapid heartbeat.

Wolff-Parkinson-White syndrome is a congenital heart defect. People with WPW syndrome have an extra path for signals to travel between the heart's upper and lower chambers. This causes episodes of a fast heartbeat. Rarely, WPW syndrome can cause sudden cardiac death.

Symptoms include a rapid, pounding or fluttering heartbeat, chest pain, dizziness, and shortness of breath. Babies with the syndrome may have skin color changes and may seem irritable.

Actions called vagal maneuvers may help slow the heartbeat. These actions include coughing or bearing down as if passing stool. Other treatments include medicines, a supervised shock to the heart or a heart procedure.