High rate of early restenosis after carotid eversion endarterectomy in homozygous carriers of the normal mannose-binding lectin genotype

Background and Purpose - Mannose-binding lectin (MBL) is thought to influence the pathophysiology of cardiovascular disease by decreasing the risk of advanced atherosclerosis and by contributing to enhanced ischemia reperfusion injury. Thus, we investigated the role of MBL in restenosis after eversion endarterectomy in patients with severe carotid atherosclerosis. Methods - In a prospective study, 123 patients who underwent carotid endarterectomy were followed-up by carotid duplex scan (CDS) sonography for 14 months. In a retrospective study, we examined 17 patients and 29 patients, respectively, who had or had not at least 50% restenosis 29 months after carotid eversion endarterectomy. MBL genotypes were analyzed by a polymerase chain reaction-based method, and MBL serum concentrations were measured. Results - In the prospective study in the patients homozygous for the normal MBL genotype, CDS values were significantly higher after 14 months of follow-up compared with the values measured 6 weeks after surgery ( P < 0.001). In contrast, only a slight increase was registered in patients carrying MBL variant alleles. The differences were much more pronounced in female than in male patients. Similar differences were observed when patients with high and low MBL serum concentrations were compared. In the retrospective study, a significant increase in the frequency of MBL variant genotypes was observed in patients not experiencing restenosis compared with the patients with restenosis ( P = 0.007). Conclusions - These results indicate that reoccurrence of stenosis after carotid endarterectomy is partially genetically determined and imply that MBL contributes significantly to the pathophysiology of this condition.