Embolic foreign material in the central nervous system of pediatric autopsy patients with instrumented heart disease

Upon detection of foreign-body embolization to the central nervous system (CNS) following a specific invasive cardiovascular procedure in 1 autopsied child, we undertook a quality assurance analysis to determine whether other patients had had similar events. Autopsies of all infants and children with history of cardiac catheterization, heart surgery on cardiopulmonary bypass, and/or extracorporeal membrane oxygenation over a 5-year period at a single tertiary care institution were reviewed for light-microscopic evidence of foreign material. Of the 24 patients meeting clinical criteria (13 females, 11 males; ages 6 days to 20 years, median age 7.5 months), 8 (33%) had foreign embolic material to the CNS. The material was associated with a cellular inflammatory reaction in all cases, with a subset associated with infarcts. No embolic foreign material was detected in 14 age-matched patients without history of cardiovascular procedures. Particles acquired from ex vivo manipulation of a catheter type utilized in at least 1 of the affected patients demonstrated similar histologic characteristics. We conclude that, in addition to recognized risks of hypoxic-ischemic brain damage in congenital cardiopulmonary disease, potential brain insult exists in the form of instrumentation-related foreign emboli to the cerebral vasculature. Cardiac catheters are a potential source of foreign embolic material.