This study is a single-center and random analysis. The consecutive hospitalized patients with ACS at Beijing Mentougou District Hospital from January 1, 2008 to December 31, 2010 were enrolled. Figure 1 is a flow diagram of the trial. There were 259 males (54.9%) and 213 females (45.1%) with an average age of 61.1 ± 11.0 years. Patient's history, physical examination, and laboratory results were recorded. All patients were divided into the Hp-negative group (Hp-, group 1.) and the Hp-positive group (Hp+). The Hp+ group were randomly divided into two groups: Group 2, the Hp+ with eradication therapy (Hp+ Therapy); and Group 3, the Hp+ without eradication therapy (Hp+No Therapy).