Two cases of migration of retained pacemaker electrodes are described. The first presented as an unusual cause of deep vein thrombosis while the second was asymptomatic and detected by routine chest x-ray. Both made a good recovery, the first with surgery and the second with the fragment left in situ. A review of the world literature revealed only 13 other such cases. Of the total of 15 cases four are known to have died. In these patients no relationship was found between morbidity and the site of migration or associated infection and/or thrombosis. However surgical treatment appeared to be associated with a better prognosis.