Coronary atherosclerotic disease is related to endothelial inflammation and dysfunction, thrombosis and plaque instability. Different inflammatory markers are studied in stable angina and coronary acute syndromes, in order to stratify better the risk and to prevent the cardiovascular events. Platelet-activating factor (PAF) and platelet activating factor acetylhydrolase (PAF-AH) represent a complex with proinflammatory actions, possibly related to progression of atherosclerotic lesions. In our study, we investigated PAF-AH activity in 30 patients with stable angina, trying to demonstrate a relation of PAF-AH activity with the severity of the coronary disease.