Clinical and electrophysiological characteristics in Korean patients with WPW syndrome.

This study was designed to investigate the clinical and electrophysiologic characteristics of WPW syndromes in Korea. A total of 400 symptomatic WPW syndrome patients were consecutively recruited. The most common documented symptomatic tachyarrhythmia was orthodromic atrioventricar reentrant tachycardia (75.3%), followed by atrial fibrillation (31.3%), and antidromic atrioventricular reentrant tachycardia (6.2%). There was a higher incidence of multiple bypass tract in patients with antidromic tachycardia than in those with orthodromic tachycardia (30.4 vs 4.3%, P < 0.001). The inducibility of tachyarrhythmia with electrophysiologic study in this study population was 95.8%. The most frequent location of the accessory pathway was the left free wall (48.0%), followed by the right free wall (29.1%), posterior septum (17.5%) and anterior septum (3.5%). These results indicated that 1) clinical and electrophysiological characteristics of Korean patients with WPW syndrome were similar to those of western countries and 2) the electrophysiologic study was important in the evaluation of patients with WPW syndrome.