title: Clinical and electrophysiologic studies on the Wolff-Parkinson-White syndrome in aged cases.
abstract: Clinical and electrophysiologic studies were performed in 10 aged cases (50-82 years of age) with WPW syndrome and following results were obtained: 1) Episodes of paroxysm of supraventricular tachyarrhythmias were observed in 7 and complication of sinus node dysfunction was noted in 3. 2) P-delta intervals on electrocardiogram exceeding 0.12 sec were observed in 4 cases. 3) Patterns of normalization of QRS complex in 4 cases were characterized by tachycardia-dependent in 2 and bradycardia-dependent in 2. 4) Effective refractory period of the accessory pathway (AP) in antegrade direction exceeded that of A-V node in 5 cases and the former exceeding 500 msec was observed in 2 cases. The relations between the changes of the electrophysiologic properties of the AP and altered clinical manifestations of the WPW syndrome in aged cases were discussed.
mesh_terms: D000367:Age Factors; D000368:Aged; D002036:Bundle of His / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014927:Wolff-Parkinson-White Syndrome / Q000503:physiopathology*