At 1 year , a composite of death , myocardial infarction , severe heart failure , or stent thrombosis occurred in 21 patients ( 6.1 % ) in the postconditioning group and 16 patients ( 4.6 % ) in the conventional PCI group ( hazard ratio [ HR ] 1.32 , 95 % CI 0.69-2 .53 , P = .40 ) .