Background and objectives: Subclavian vein thrombosis is a well-recognized complication following central venous catheter insertion. We studied whether the determination of D-dimer levels, fragment 1+2 levels and factor V Leiden can identify patients at high risk of developing subclavian vein thrombosis.
Design and methods: The presence of central venous catheter associated thrombosis was analyzed in 235 patients undergoing allogeneic bone marrow transplantation, of whom 30 (13%) developed thrombosis. A case-control study was performed with 30 patients matched for age, gender, and type of transplantation who did not develop thrombosis. Blood was sampled 3-5 days after catheter insertion. D-dimer levels were determined using a latex microparticle assay and an enzyme linked immunosorbent assay (ELISA). An ELISA was used to determine fragment 1+2 levels. The factor V genotype was determined by polymerase chain reaction.
Results: The levels of D-dimer and fragment 1+2 were significantly elevated in the patients who developed thrombosis. Five patients tested positive for factor V Leiden and all 5 developed subclavian vein thrombosis. Patients with high D-dimer levels (> 1300 microg/L measured by latex agglutination and >350 microg/L measured by ELISA) had a 7.0 and 6.0 times higher risk of developing subclavian vein thrombosis, respectively. A 5.5-fold increased risk of thrombosis was observed in patients with a fragment 1+2 level higher than 1.300 nmol/L. This resulted in positive predictive values of 0.78, 0.80 and 0.83 for the fragment 1+2, D-dimer and D-dimer latex agglutination assays, respectively. The accompanying negative predictive values were 0.39, 0.40 and 0.42, respectively.
Interpretation and conclusions: We conclude that the measurement of D-dimer and fragment 1+2 levels after central venous catheter insertion, as well as factor V Leiden determination, can be used to identify patients at high risk of developing symptomatic subclavian vein thrombosis.