S100B as a predictor of size and outcome of stroke after cardiac surgery.
BACKGROUND
Stroke after cardiac surgery is a clinical problem with often fatal or disabling outcome. To assess severity and probable outcome in affected patients only from clinical and radiological examinations is difficult. The glial-derived protein S100B has been suggested to be a marker of cerebral ischemia, and increased blood concentrations of S100B have been shown to correlate with size of lesion and prognosis after stroke. We studied the validity of S100B as a predictor of size of brain lesion and median term outcome in a consecutive group of patients suffering from stroke after cardiac surgery.


METHODS
During a period of 17 months, 20 patients with clinical signs of postoperative stroke were investigated with S100B measurement, sampled at 5, 15 and 48 hours after surgery. All patients were examined with computed tomography or magnetic resonance imaging to confirm the diagnosis, and the size of cerebral infarction was estimated from the radiological examinations. The patients were followed up for survival 24 to 39 months after surgery.


RESULTS
S100B concentration in blood 48 hours after surgery correlated with the size of infarcted brain tissue (r = 0.68, p < 0.001). Nine patients had S100B levels exceeding 0.5 microg/L and a 2-year mortality of 78%, whereas the 11 patients with S100B below 0.5 microg/L had a mortality of 18%.


CONCLUSIONS
Increased S100B in patients with a stroke following cardiac surgery correlate with the size of infarcted brain tissue. High S100B levels 48 hours after surgery have a negative predictive value for median term survival.
Jönsson
H
H
Department of Cardiothoracic Surgery, University of Lund, Sweden. henrik.jonsson@thorax.lu.se
Johnsson
P
P
Birch-Iensen
M
M
Alling
C
C
Westaby
S
S
Blomquist
S
S
D000368:Aged; D019917:Blood Vessel Prosthesis Implantation; D002135:Calcium-Binding Proteins / Q000097:blood*; D001026:Coronary Artery Bypass; D005260:Female; D005500:Follow-Up Studies; D019918:Heart Valve Prosthesis Implantation; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D009414:Nerve Growth Factors / Q000097:blood*; D011183:Postoperative Complications / Q000097:blood* / Q000175:diagnosis / Q000401:mortality; D011379:Prognosis; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; D020521:Stroke / Q000097:blood* / Q000175:diagnosis / Q000401:mortality; D015996:Survival Rate
D002135:Calcium-Binding Proteins; D009414:Nerve Growth Factors; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; C579160:S100B protein, human