Does inherited thrombophilia contributes thrombosis in microvascular free flap surgery:  a pilot study.

Drizlionoka Gorovenko K,1,2 Stepanovs J.,1,2 Ozolina A.,1 Nikitina-Zake L.,3  Mamaja B.1,2
 1 Riga Stradins University, Latvia
 2Riga East Clinical University Hospital, Latvia
  3Latvian Biomedical Research and Study Center, Latvia

Background and Goal of study: The role of microvascular surgery as a part of reconstructive surgery is enhancing and has been technically improved, nevertheless mishap due to thrombosis still occures delaying restitution, thus bearing detrimental effect for patient, medical team and expenses. Hereditery thrombophilia is a well known factor possessing increased risk for vascular events, however still beyond the scope of microvascular surgery. The goal of the study is to educe whether link between genetic factors and likelihood of thrombosis in microvascular free flap surgery exists.
Material and Methods: A total of 60 patients who have undergone free flap microvascular surgery were enrolled in the cohort study, we selected nine single nucleotide polymorpisms (SNPs) (rs5361 in SELE, rs2066865 in FGG, rs2227589 in SERPINC1, rs1613662 in GP6, rs13146272 in CYP4V2, rs2289252 in F11, rs1801133 in MTHFR, rs6025 in F5, rs1799963 in F2 ) reported to be associated with vascular thrombosis.
Results and Discussion: In 10/60 (17 %) patients free flap failure due to thrombosis occured. We found SNP rs2289252 in F11 and rs13146272 in CYP4V2 in 7 and 5 patients in thrombosis group, respectively. Occurrence in non- thrombotic group of same SNPs is common either, both indicating high prevalence in observed population. rs6025 FV Leiden and rs1799963 FII were found in nonthrombotic group but none in thrombotic group. rs2227589 in SERPINC1 were identified in 4 patients with flap thrombosis and in 10 patients with non-thrombosis, including those (6) having perioperative thromboprophylaxis due to co-morbidities. rs1613662 in GP6 along with history of myocardial infarction prior age of 45 were identified in 3 patients in non- thrombosis group with thromboprophylaxis. Several SPNs combinations in thrombotic patients group were detected however no correlation was defined yet.                                                         Conclusion: Several gene polymorphisms are found in patients with thrombotic complications indicating a potential cause of microvascular free flap thrombosis likely synergistic with other well known thrombophilia contributing factors. Further data are mandatory and greater sample size is needed to set relationship between gene mutation and thrombosis in free flap surgery.