Perioperative time course of matrix metalloproteinase-9 (MMP-9), its tissue inhibitor TIMP-1 & S100B protein in carotid surgery

BACKGROUND & OBJECTIVES: Ischaemic stroke is a life burdening disease for which carotid endarterectomy (CEA) is considered a gold standard intervention. Pro-inflammatory markers like matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) and S-100 Beta (S100B) may have a role in the early inflammation and cognitive decline following CEA. This study was aimed to describe the perioperative time courses and correlations between of MMP-9, TIMP-1 and S100B following CEA. METHODS: Fifty four patients scheduled for CEA were enrolled. Blood samples were collected at four time points, T(1): preoperative, T(2): 60 min after cross-clamp release, T(3): first postoperative morning, T(4): third postoperative morning. Twenty atherosclerotic patients were included as controls. Plasma MMP-9, TIMP-1 and S100B levels were estimated by ELISA. RESULTS: TIMP-1 was decreased significantly in the CEA group (P<0.01). Plasma MMP-9 was elevated and remained elevated from T(1-4) in the CEA group (P<0.05) with a marked elevation in T(3) compared to T(1) (P<0.05). MMP-9/TIMP-1 was elevated in the CEA group and increased further by T(2) and T(3) (P<0.05). S100B was elevated on T(2) and decreased on T(3-4) compared to T(1). INTERPRETATION & CONCLUSIONS: Our study provides information on the dynamic changes of MMP-9-TIMP-1 system and S100B in the perioperative period. Preoperative reduction of TIMP-1 might be predictive for shunt requirement but future studies are required for verification.