Early observations that the regular use of
aspirin (
acetylsalicylic acid, ASA), a
nonsteroidal anti-inflammatory agent, seemed to protect against
myocardial infarction and reduce platelet aggregation made this substance the most frequently used
drug in large clinical trials. The objectives of these studies were to reduce thromboembolic complications in arterial
cardiovascular diseases (prevention of
myocardial infarction in
unstable angina,
secondary prevention of acute
myocardial infarction, and increased patency of
aortocoronary bypass grafts) and to reduce platelet deposition on artificial surfaces (
artificial heart valves and
hemodialysis shunts). Despite the recent synthesis of more selective inhibitors of
arachidonic acid metabolism in blood platelets, and a multitude of questions concerning optimal dose, schedule, and mode of action that still remain open, ASA continues to be the most frequently used
drug in arterial vascular disorders. Because of the frequent and potentially serious side effects of
aspirin, mainly on the gastrointestinal tract, less toxic ways of inhibiting
eicosanoid metabolism in blood platelets are attracting more and more interest. Among these, the alimentary substitution of
omega-3 fatty acids for a competitive inhibition of the omega-6-arachidonic
acid metabolism seems the most promising. Results with
fish-oil diet raise the question of whether substitution of polyunsaturated
lipid acids influence only platelet metabolism, or whether the action of "anti-platelet" drugs or diet in cardiovascular disorders is mediated primarily by leukocytes or monocytes. This new dietary principle, which possibly corrects only a poor alimentary habit of civilization, could open simple and adequate ways for even a primary prophylaxis of
vascular disease by diet alone or, at least for therapeutic aims, in combination with drugs.