How many people are affected by Wolff-Parkinson-White syndrome ?
Wolff-Parkinson-White syndrome affects 1 to 3 in 1,000 people worldwide. Only a small fraction of these cases appear to run in families.  Wolff-Parkinson-White syndrome is a common cause of an arrhythmia known as paroxysmal supraventricular tachycardia. Wolff-Parkinson-White syndrome is the most frequent cause of this abnormal heart rhythm in the Chinese population, where it is responsible for more than 70 percent of cases.