We randomly assigned 254 patients undergoing coronary stent follow-up with the use of MDCT-CA to iomeprol-400 at 5.0 mL/sec flow rate ( group 1 ; n = 83 ) , iodixanol-320 at 6.2 mL/sec flow rate ( group 2 ; n = 87 ) , and iodixanol-320 at 5.0 mL/sec flow rate ( group 3 ; n = 84 ) .