Inherited thrombophilias in thrombosis advancement in microvascular flap surgery

Microvascular flap surgery is a reliable method for reconstructive surgery. To avoid and foresee free flap thrombosis advancement after microvascular flap surgery, patient assessment, flawless surgical technique, and eligible perioperative care are pivotal. In this prospective observational study, we aimed to elucidate the most common inherited single nucleotide polymorphisms (SNPs) attributable to free flap thrombosis. A total of 152 patients undergoing microvascular flap surgery during the study period of 2016–2019 were analysed for five SNPs: rs6025 in Factor V Leiden (FVL) gene, rs1799963 in Factor II (FII) gene, rs2066865 in Fibrinogen Gamma Chain gene (FGG), rs2227589 in SERPINC 1 gene and rs1801133 in Methylene Tetrahydrofolate Reductase (MTHFR) gene. Activated protein C resistance (aPCR), prothrombin, antithrombin (AT), fibrinogen and homocysteine plasma levels were measured to determine association with the analysed SNPs and with free flap thrombosis advancement. Our preliminary results show that carriers of FVL mutation were associated with aPCR, as we observed significantly lower aPCR plasma levels in carriers of genotype C/T, as compared to C/C; p = 0.006 (CI 95%, 0.44 to 1.19). Additionally, mean fibrinogen plasma levels were higher in carriers of FGC gene rs2066865 genotype A/A (5.6 ± 1.81 g/l), as compared to G/A and G/G; p = 0.04 (CI 95%, 0.007 to 1.09); p = 0.004 (CI 95%, 0.48 to 2.49), respectively. The study group included 12 patients (7.9%) with free flap thrombosis. For one patient free flap thrombosis advancement might have been related to the rs6025T – FVL mutation with a PCR plasma level 1.21. Lower aPCR levels was associated with carriers of FVL rs6025 C/T and higher fibrinogen plasma levels with carriers of FGG rs2066865 A/A, suggesting that these genotypes might predict higher free flap thrombosis risk, but we found no significant association between analysed SNPs and free flap thrombosis advancement.