Suspected Somatosensory Evoked Potentials Pacing Atria During Cerebral Bypass Surgery: A Case Report.

Somatosensory evoked potentials are commonly utilized during surgery to assess the function of the central nervous system. We present a case of a 48-year-old female patient undergoing cerebral bypass surgery who was noted to have reproducible, stimulation frequency-dependent heart rate changes that coincided with somatosensory evoked potentials stimulation. We hypothesize that the somatosensory evoked potential stimulation current was depolarizing a foci of atrial myocytes, resulting in the initiation of the cardiac cycle.