Recent studies have demonstrated that newly diagnosed abnormal glucose tolerance (AGT; diabetes mellitus and impaired glucose tolerance) are common among the patients with ischemic heart disease. Several large cohort studies indicate that people with prediabetic conditions, such as impaired glucose tolerance, have a raised risk of future cardiovascular disease. Intervention with acarbose can prevent myocardial infarction and cardiovascular disease in type 2 diabetic and IGT patients. However, the effect of acarbose to secondary prevention of myocardial infarction or cardiovascular events in patients with newly diagnosed AGT after coronary stenting remains unclear. The purpose of the present study is to determine whether the intervention to such abnormalities after coronary stenting will improve the long-term clinical outcome. This is a opened, randomized study to compare acarbose versus a standard lifestyle modification. Patients will have a 1:1 chance of receiving acarbose versus the standard lifestyle modification. There is some research evidence that suggests acarbose may improve clinical outcome in patients with type 2 diabetes and in IGT patients.