MODEL RELEASED. Balloon angioplasty. Male patient undergoing balloon angioplasty in an operating theatre. The surgeon (at right) is inserting a balloon catheter into the patient. The radiographer (at left) monitors the procedure on an X-ray screen. Angioplasty is a technique for treating the narrowing or blockage of blood vessels or a heart valve. A deflated balloon catheter is inserted into the affected area. The balloon is inflated to stretch the constricted area and hence increase blood flow. The procedure is carried out under local anaesthetic. Angioplasty is used to treat atherosclerosis where fat deposits narrow blood vessels.