SUPERIOR VENA-CAVA THROMBOSIS RELATED TO CATHETER MALPOSITION IN CANCER-CHEMOTHERAPY GIVEN THROUGH IMPLANTED PORTS

Background. Thrombosis of the central veins is one of the most frequen t complications of implanted venous access devices. Among the first ca ses occurring in our patients, most were associated with left-sided pl acement of the ports, with catheter tips lying against the external wa ll in the upper half of the superior vena cava. Some chest radiographs showed lateromediastinal opacities centered on the catheter tip, sugg esting a vessel injury. This position allows a narrow contact between the catheter tip and the vessel wall, thus endothelial injuries might result from mechanical and chemical attack. Methods. To assess the rol e of catheter position, we reviewed the routine chest radiographs of 3 79 patients who received chemotherapy through venous access devices an d were followed up at our department between December 1985 and Decembe r 1990. Four groups (upper left, upper right, lower left, and lower ri ght) were defined according to the level of the catheter tip (innomina te veins or upper half of the vena cava versus lower half of the vena cava or auricula) and to the side of port implantation. Results. Ten p atients developed symptomatic venous thrombosis (superior vena cava in 9 patient, left subclavian vein in 1 patient). A strong correlation e xisted between catheter position and incidence of thrombosis: upper le ft, 8/28 (28.6%); upper right, 1/33 (3%); lower right, 1/68 (1.5%); an d lower left, 0/250. Since 1988, we have insisted on replacement of ma lpositioned catheters, and we have observed fewer thromboses (2/191 ve rsus 8/188). Conclusions. The current study suggests that patients wit h left-sided ports and catheter tips lying in the upper part of the ve na cava are at high risk for severe thrombotic complications.