Oral anticoagulation is one of the oldest ways for preventing secondary ischemic heart disease. With the introduction of aspirin, and low-dose aspirin in particular, the interest in oral anticoagulants has diminished, given the inherent bleeding risk. This short review deals with the efficacy and safety of oral anticoagulation in treating ischemic heart disease compared to placebo and to low-dose aspirin. Also, the comparison of the combination of oral anticoagulants and aspirin to aspirin alone is made. After myocardial infarction, oral anticoagulation is far superior to placebo in preventing recurrent ischemic events, with a risk of major bleeding of 1 per 100 patient-years. Oral anticoagulation seems equivalent to aspirin after myocardial infarction, but shows the same excess bleeding. Clearly, aspirin is, therefore, preferable for this indication. Combination therapy with oral anticoagulants and aspirin seems superior to aspirin alone provided the international normalized ratio is kept over 2.0. Also, here bleeding occurs in 1 out of 100 patient-years and the risk must be weighed against the risk of recurrent ischemic events. In coronary angioplasty, warfarin given before intervention looks promising in one large trial, but when given after intervention it is not beneficial and leads to more bleeding. Long-term oral anticoagulation does not lead to better graft patency after coronary surgery, but in one large trial it did lead to a better rate of survival.