Lipid abnormalities in myocardial cell injury.

Considerable evidence indicates that abnormalities in fatty acid and phospholipid metabolism are important in the pathogenesis of the membrane dysfunction that leads to irreversible myocardial cell injury during myocardial ischemia and related conditions. Membrane dysfunction is mediated by phospholipid degradation and by the accumulation of amphipathic lipid species, including free fatty acids, long-chain acyl-coenzyme A esters, long-chain acylcarnitines, and lipid peroxides. Accumulation of free arachidonic acid, a fatty acid normally stored in membrane phospholipids, is a sensitive indicator of phospholipid degradation. Ongoing work is aimed at defining mechanisms of the phospholipid alterations that appear to involve phospholipase-mediated phospholipid catabolism and impaired phospholipid synthesis.