Objective: To investigate the relationship between Helicobacter pylori (Hp) infection and the prognosis of acute coronary syndrome (ACS) in a Chinese population and to explore the significance of Hp eradication therapy in preventing major adverse cardiac events (MACE) and upper gastrointestinal bleeding (UGIB) in patients on dual antiplatelet treatment. Methods: To analyze 472 ACS patients with drug-eluting stent (DES) implantation from January 1, 2008 to December 31, 2010 in the department of cardiology at Beijing Mentougou District Hospital. Patients were divided into three groups: Group 1, the Hp-negative patients (Hp-); Group 2, the Hp-positive patients with eradication therapy (Hp+ Therapy); and Group 3, the Hp-positive patients without eradication therapy (Hp+ No Therapy). All patients took 13C urea breath test, high sensitive C-reactive protein (hs-CRP)，homocysteine (HCY) and other biochemical indicators. The investigators explored the correlations of Hp eradication therapy with MACE (including recurrent myocardial infarction, revascularization and death) and UGIB after 3 to 5 years of follow-up using survival analysis.

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).

Inclusion Criteria:

• Patients were diagnosed acute coronary syndrome according to the 2012 ESC guidlines.
• All the patients took dual antiplatelet therapy after implanting drug eluting stent (DES) during hospitalization and had no any digestive symptoms.

Exclusion Criteria:

• Subjects who had suffered gastrointestinal bleeding within one week.
• Subjects had a history of gastrectomy, cardiac insufficiency, thyroid dysfunction, and any ongoing infections were eliminated.
• Patients with the use of antibiotics, bismuth, or sucralfate within one month and without impanting DES because of ACS during hospitalization were also excluded.
• Those who had gastrointestinal symptoms, such as acid reflux, heartburn, nausea, vomiting, stomach ache and diarrhea, or had a confirmed peptic ulcer with Hp infection were excluded because these patients may be taken gastroenterology treatment.

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).