A 65-year old woman presented with acute or chronic renal failure and signs of right heart failure. Renal replacement therapy—using a surgically placed dialysis catheter via the left jugular vein—was repeatedly complicated by altered flows of the dialysis unit, impaired consciousness, new onset of seizures and left-sided hemiparesis. The tip of the dialysis catheter was detected on transesophageal echocardiography within the lumen of the ascending aorta. Further imaging of the neck vessels demonstrated a primary placement of the catheter in the left common carotid artery. This incident underscores the value of ultrasound guidance for placement of intravascular catheters.