Changes in platelet membrane fatty acids after myocardial infarction.

Myocardial infarction (MI) is a common cause of morbidity and mortality, and platelets may contribute to its development. Platelet membrane composition can influence platelet function. In this study changes in platelet membrane fatty acids with time following MI were explored. Platelet membrane fatty acid profiles were studied in 40 patients after MI, at a mean of 8 days, and compared with a control group of 17 subjects awaiting minor surgery. They were restudied at 1 month and 3 months. Significant changes were found within the patient group in 18:1, which fell with time (19.99% +/- 1.24 to 18.73% +/- 1.16 at 3 months, P less than 0.001), 22:3 + 24:1, which also fell (1.97% +/- 0.48 to 1.46% +/- 0.49, P less than 0.001), and in 18:2, which increased (3.92% +/- 0.77 to 5.04% +/- 1.15 P less than 0.001). Comparison with controls showed no significant differences at baseline, a small increase in 22:4 at 1 month and 3 months in MI group and a decrease in 22:3 + 24:1 in MI group at 3 months. No changes were noted in 20:4, 20:5 or in the polyunsaturated/saturated fatty acid ratio. The explanation for these findings is not known. The possible influence of diet and other factors is discussed.