Inclusion Criteria:  Clinical diagnosis of STEMI To undergo emergency PCI treatment Palpable pulsation of the radial artery and distal radial artery  Exclusion Criteria:  Arteriovenous fistula of radial artery and cephalic vein has been performed with regular hemodialysis Suspicious left main block of electrocardiogram Had used the radial artery percutaneous interventional treatment before Cardiogenic shock