A 29-year-old man developed recurrent syncope following exertion. Cardiac i
nvestigations revealed no evidence of structural heart disease, but during
exercise testing, in the recovery phase, he sustained a bradycardia and the
n asystole for a prolonged period. Before cardiac massage could be institut
ed a tonic-clonic fit occurred, and this initiated a return to sinus rhythm
. His symptoms were abolished following the implantation of a dual-chamber
pacemaker.