Vascular ultrasound is an established technique in shunt diagnostics for hemodialysis fistulas that allows non-invasive diagnosis of vascular morphology and hemodynamics. Early detection of shunt stenoses in hemodialysis fistulas or thrombotic occlusions facilitates an interventional decision. High occlusion rates of up to 45% within 1 year in hemodialysis fistulas due to reduced flow volume justify follow up with vascular ultrasound examination. The use of high resolution transducers in vascular ultrasound enables complications, such as stenoses and occlusions to be recognized early therefore allowing preemptive therapy. In the present review the examination technique and strategy, the most important complications and treatment options will be discussed.