Thoracic endovascular aneurysm repair(TEVAR) has been applied more and more frequently to an atherosclerotic distal aortic arch aneurysm. Even if the procedure is successful, extensive cerebral infarction might occur, especially in the left vertebral artery area. We therefore devised a new method to prevent embolic events using a thrombectomy catheter with an end hole, which was placed at the origin of the letf subclavian artery via the radial artery. This simple left subclavian artery balloon technique not only prevents cerebral embolism in the left vertebral artery system, but also provides a position marker under X-ray, and enables tight compaction of the embolization coils.