Percutaneous interventions for vascular dialysis access.

A prerequisite for the long-term patency of vascular access is early detection of a failing shunt, i.e., at the stage of stenosis. Fistulography performed to locate the lesion is followed by percutaneous transluminal angioplasty using a balloon catheter. The procedure takes 30-60 minutes to complete; the clinical success rate varies between 85% and 98%. A more serious condition of failled vascular access is its occlusion secondary to thrombosis. The high costs of hospitalisation and treatment of thrombosed shunts require effective yet less invasive outpatient procedures. Recent years have seen an explosion in the development of mechanical devices on the principle of mechanical dissolution, fragmentation, and aspiration of the clot. Post-procedural dialysis can be performed immediately thus reducing the need for a central venous catheter. The procedure, particularly in the treatment of native fistula occlusion, is more complicated and about twice as time consuming as treatment of stenosis. The clinical success rate is usually between 71% and 100%. The incidence of serious complications of percutaneous treatment is low.