Cat naps: an elderly woman with recurrent syncope

An otherwise healthy 87-year-old woman who was not taking medications presented to our emergency department after experiencing an episode of presyncope. While in the emergency department the woman, whose baseline heart rate was 72 beats/min, experienced multiple witnessed episodes of vomiting, presyncope and syncope, each lasting about 30 seconds. The episodes were associated with sinus pauses of 3-4 seconds' duration observed on the patient's cardiac monitor and appeared to be precipitated by neck movement to either side. The episodes could also be reproduced with light palpation of the right carotid artery but not the left. The top panel of Fig. 1 depicts part of an electrocardiogram taken during a brady-cardiac episode (heart rate 25 beats/min) precipitated by massage of the right carotid artery. The bottom panel of Fig. 1 (heart rate 65 beats/min) shows a lack of cardiac response to palpation of the left carotid artery. The remainder of the clinical examination, laboratory work-up and electrocardiogram were within normal limits except for evidence of a urinary tract infection on routine urinalysis. There were no signs of orthostatic hypotension or valvular heart disease on cardiac auscultation.