SELF-EXPANDING METAL STENTS FOR PALLIATIVE TREATMENT OF SUPERIOR VENA-CAVAL SYNDROME

Purpose: Two stent types (a new Wallstent and a Z-stent) were investig ated in 30 patients with recurrent malignant superior vena caval syndr ome (SVCS). Methods: Eligibility requirements were that the patient ha d recurrent symptoms after appropriate radiation therapy, chemotherapy , or both; greater than or equal to 75% of the vessel was occluded; an d there was collateral flow. Because of the limited availability of st ents, it was not possible to perform a prospectively randomized study. Results: In the Z-stent group (17 patients), occlusion of the stent d ue to acute thrombosis occurred within 12 hr in 4 patients (24%), but in the other 13 patients (76%) symptoms disappeared completely. After 2 weeks the cavogram in these patients showed no signs of thrombosis, and 12 (71%) of the patients remained symptom-free. There was partial occlusion in 5 patients (29%), without relevant clinical symptoms. Of the 13 patients who received Wallstents, only 1 had an acute immediate thrombosis (8%). Symptoms disappeared completely in the other 12 pati ents and no signs of thrombosis were seen. However, after 2 weeks comp lete stent occlusion with SVCS was found in 3 patients (23%) and parti al occlusion with minor clinical symptoms in 6 (46%). Only 3 patients (23%) had complete relief of their SVCS. The difference between the ra tes of occlusion of the two stents after 2 weeks was highly significan t (p = 0.008). Conclusions: The overall clinical success rate for long term patency was 100% for the Z-stents and 69% for the new Wallstent. These results suggest that when used for this purpose, the new Wallste nt is more thrombogenic at 2 weeks than the Z-stent.