Bradycardia-Tachycardia Syndrome Due to Sinus Node Disease and Concealed Wolff-Parkinson-White Syndrome.

A 75-year-old woman was admitted to the hospital because of a supraventricular tachycardia, long sinus pauses and ventricular tachycardia of the torsades de pointe type. Temporary ventricular pacing suppressed ventricular arrhythmias but supraventricular tachycardia persisted. An electrophysiologic study revealed the coexistence of sick sinus syndrome and circus movement tachycardia due to a concealed left-sided accessory atrioventricular pathway. This case represents a previously undescribed form of the bradycardia-tachycardia syndrome. [ABSTRACT FROM AUTHOR]