Respiratory and cardiac abnormalities in brain-stem ischaemia.

Two patients are presented who had suffered episodes of ischaemia of the brain-stem, mainly affecting one side of the pons. In addition to the more usual neurological signs, these two patients had cardiac arrhythmia: one had a sinus arrhythmia, the other a wandering pacemaker. In both patients the hemidiaphragm on the side ipsilateral to the lesion was transiently elevated. The mechanisms responsible for the arrhythmia and the elevated hemidiaphragm are discussed.