Serum S-100 Protein in Stroke and Cardiac Surgery

Abstract

To the Editor: We have read with interest the articles1 2 3 and correspondence4 of Butterworth and Missler, which dicusses the correlation of S-100 protein release with cerebral infarction and hemorrhagic strokes. The authors suggest that S-100 protein levels may be a reliable index of the mass of injured brain and the patient’s prognosis and may facilitate differentiation of hemorrhagic and nonhemorrhagic strokes. However, we would like to report that this use of S-100 protein to estimate the extent of cerebral damage cannot be extrapolated to other clinical scenarios in which cerebral injury may occur. Open-heart surgery is associated with a small but significant incidence of stroke. Surgery requiring hypothermic circulatory arrest for reconstruction of the aortic arch is associated with an incidence of stroke of 5% to 12%5–7; that for coronary artery bypass grafting (CABG) is 3% to 6%.8 Several biochemical markers of cerebral injury have been investigated as potential substitutes for serial neuropsychological assessment in studies assessing different methods of cerebral protection during surgery.9 We measured serum S-100 protein in 10 patients undergoing CABG using simple mild hypothermic cardiopulmonary bypass and in 30 patient with thoracic aortic aneurysms using profound hypothermic cardiopulmonary bypass and circulatory arrest (HCA) for up to 60 …