Central venous occlusion in hemodialysis access: Comparison between percutaneous transluminal angioplasty alone and nitinol or stainless-steel stent placement.

PURPOSE: The purpose of this study was to compare the primary and secondary patency rates of percutaneous transluminal angioplasty (PTA) alone with those of metallic stent placement in patients with hemodialysis access and central venous occlusion (CVO) and to compare the respective effects of nitinol and stainless-steel stents on patency. MATERıALS AND METHODS: A total of 150 consecutive patients with hemodialysis access who underwent endovascular treatment for symptomatic CVO with ipsilateral functioning hemodialysis access were evaluated. There were 67 men and 83 women with a mean age of 56.2±15.2 (SD) years (range: 15-86 years). The primary endovascular treatment of CVO was PTA alone. Stent placement either with nitinol or stainless-steel stents was performed as a bailout procedure. The results were analyzed on a per patient basis.

RESULTS: Technical success was achieved in 141/150 patients (94%). Of the 141 patients, 109 (77%) underwent PTA alone and 32 (23%) underwent stent placement. The mean number of interventions in the stent group [4.3±2.5 (SD)] was significantly higher than that in the PTA alone group [2.6±2.8 (SD)] (P=0.002). The primary patency rates at 12, 24, and 60 months for the stent group (58.7%, 41.9%, and 27.9%, respectively) were significantly higher than those in the PTA alone group (42.4%, 36.3%, and 20.2%, respectively) (P=0.036). Secondary patency rates at 12, 24, and 60 months for the stent group (87.6%, 80.7%, and 50.3%, respectively) were significantly greater than those in the PTA alone group (68.4%, 56%, and 38.6%, respectively) (P=0.046). Furthermore, the primary patency rates at 6 and 12 months in the nitinol stent group (89% and 80.9%, respectively) were significantly greater than those in the stainless-steel stent group (78.8% and 38.4%, respectively) (P=0.007). The secondary patency rates at 6, 12 and 24 months for the nitinol stent group (92.8%, 87.7% and 65.8%, respectively) were significantly greater than those in the stainless-steel stent group (85.7%, 76.2% and 65.3%, respectively) (P=0.011). CONCLUSıON: Although PTA alone is an effective interventional treatment strategy of CVO in short term, stent placement yields greater primary and secondary patency rates in the long-term. But the mean number of interventions per vein after stenting is significantly higher. Close follow-up and multiple re-interventions are necessary to ensure long-term patency.