CASE PRESENTATION
A 62-year-old woman with history of hypertension underwent selective coronary angiography because of intermittent chest pain for 10 days. The right radial artery was the access of choice. After easy cannulation, 5 French multifunctional angiography catheter (Terumo Corporation) was introduced into aortic sinus. Initially, subclavian tortuous anatomy made catheter rotation redundancy, and then the pressure curve was partial dampening, and with fluoroscopy it revealed an outright knot within right brachial artery (Fig 1). Gentle traction or rotation did not allow catheter withdrawal. We decided to untwist the catheter knot by balloon internal fixation and the details were as follows: Cut off the tail of discounted catheter and the tip of 6 French EBU3.5 guiding catheter (Medtronic). A 2.0×20mm balloon(Sprinter legend,Medtronic) passed through the cut guiding catheter from tail to tip(Fig 2) and then passed through the cut angiography catheter(Fig 3). When the balloon all passed through the cut angiography catheter, the balloon was given atmospheric pressure of about 14 atm and make sure that the balloon and the angiography catheter contact tightly (Fig 4). The guiding catheter was pushed to the knot point along angiography catheter by left hand. The balloon was pulled out gently under fluoroscopy and the knotted catheter was pulled out successfully (Fig 5). During the whole traction period, there was no discomfort of patient and the tip of angiography catheter was complete. Contrast was injected from the sheath to confirm patency of the brachial artery. After 10 days’ follow up, there was no discomfort in right upper limb of the patient.