Groshong catheter-associated subclavian venous thrombosis.

Purpose: To identify factors associated with the development of clinically significant venous thrombosis in cancer patients with long-term indwelling subclavian Groshong catheters (GC). Also, to assess both the subsequent performance of affected catheters and the effect of heparin and warfarin therapy on subsequent catheter function and longevity.
Methods: Longitudinal study of the outcome of clinical practice. Subset analysis of those catheters developing catheter-related venous thrombosis (CRVT).
Results: Thirty-seven cases of CRVT were identified in a population of 255 consecutive patients in whom a GC was inserted. Seventy percent of the thrombi occurred after an episode of previous catheter dysfunction; only 30% of the thrombi occurred de novo. An unexpectedly high risk of thrombosis was associated with insertion into the left-subclavian circulation (25 of 35 versus 135 of 220, p = 0.02) or with an antecedent episode of aspiration difficulty ("ball-valve effect" [BVE]) (20 of 35 versus 60 of 220, p < 0.01). No correlation was identified between thrombosis and tumor type, tumor histology, or preexisting medical disorders. Once identified, 79% of the involved patients received anticoagulant therapy with sequential heparin and warfarin. Overall longevity of the catheters preserved by anticoagulation (mean dwell = 202 days) far exceeded catheter longevity among the population of catheters that never developed thrombosis (mean dwell = 142 days). The mean catheter longevity after thrombosis (169 days) also exceeded the mean dwell time of all other catheters that were complication-free.
Conclusions: CRVT is more likely in patients in whom the catheter is inserted in the left-subclavian circulation or who have experienced a previous episode of aspiration difficulty with the catheter (BVE). Catheter preservation with sequential heparin and warfarin therapy precludes the need for catheter removal and extends dramatically the useful life of the catheter.