The aim of this study is to evaluate the efficacy of proton pump inhibitor (PPI), comparing to the mucosal defensive drug, in the prevention of the recurrence of gastric and/or duodenal ulcers during 12 weeks observation in patients receiving low-dose aspirin for vascular protection.

The events of recurrence of gastric and/or duodenal ulcers will be evaluated due to a blinded manner by specialized endoscopists at pre- and post administration during 12 weeks administration of PPI (Rabeprazole sodium 10 mg or 20 mg tablet once a day) or the mucosal defensive drug (Gefarnate 50mg Capsule twice a day).

Inclusion Criteria:

• patients with ischemic heart failure or vascular disease of brain
• patients taking low-dose aspirin to prevent relapse of vascular diseases
• patients who experienced gastric and/or duodenal ulcers before the study by the endoscopy
• patients without active gastric and duodenal ulcers
• more than 20 years old
• outpatients
• patients written an informed consent

Exclusion Criteria:

• patients with ischemic heart failure, which are acute phase, unstable condition or under 6 months after stent-instillation
• patients with brain vascular disease , which are acute phase, unstable condition or under 3 months after the first attack
• patients who are uncontrolled and complicated disease, for example thrombocytopenia, and unsuitable for this study as judged by investigator
• patients who are treated with steroid hormones
• patients who are women of, pregnant and lactating and childbearing
• patients who are alcoholism
• patients who show the hypersensitivity for test drugs
• patients who are enrolled in another clinical study
• patients who are judged as unsuitable by investigator