Elevated levels of D-dimer and fragment 1+2 upon central venous catheter insertion and factor V Leiden predict subclavian vein thrombosis.

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.