[A case of intermittent Wolff-Parkinson-White syndrome caused by high spinal anesthesia]

We experienced a case of intermittent Wolff-Parkinson-White (WPW) syndrome following spinal anesthesia. This patient had neither any past history of cardiac symptoms nor any abnormal finding in the preoperative electrocardiogram. Soon after spinal anesthesia, the level of anesthesia spread to C6. Both abbreviated PR intervals and delta waves characteristic of WPW syndrome appeared on the electrocardiogram monitor. These abnormal wave-forms continued throughout the operation, but disappeared after three days. This case was diagnosed as intermittent WPW syndrome based upon these observations. High spinal anesthesia effectively blocks the cardiac sympathetic nerve and suppresses the normal atrioventricular conduction. Further, conduction by the accessory pathway is facilitated by the relative excitement of parasympathetic nerve. In the present case, the conduction by the accessory pathway, which had originally been very poor, was transiently promoted by the above-mentioned mechanism, and abnormal wave-forms characteristic of WPW syndrome appeared temporarily in the electrocardiogram.