Graft thrombosis should be treated without unnecessary delay and within 48 hours, at least before the next dialysis session. Early declotting allows for immediate use of the access without the need for a central venous catheter. There is always a compact “arterial plug” present. Old thrombi (>5days) are often fixed to the vessel wall beyond the venous anastomosis, making surgical extraction more difficult. This is less problem for the radiological treatment.