Quantitative and qualitative serum lipoprotein analysis. Part 2. Studies in male survivors of myocardial infarction.

The fasting concentration of cholesterol and triglycerides in serum and in very low (VLDL), low (LDL) and high (HDL) density lipoproteins (LP) was determined 3 months after a myocardial infarction (MI) in 54 men, and the values obtained were compared to those in 61 healthy male control subjects. The mean triglyceride concentration in MI patients was significantly increased in serum, VLDL, LDL and HDL by 74%, 110%, 30% and 12% respectively, compared to controls. The mean cholesterol concentration was significantly raised by 16%, 120% and 14% in serum, VLDL and LDL but decreased by 22% in HDL. Hypertriglyceridaemia occurred in 58% of MI patients. Of these patients, two-fifths had hypertriglyceridaemia only and three-fifths had combined hyperlipidaemia. The hypertriglyceridaemia was caused by elevation of only VLDL triglycerides in 26%, only LDL triglycerides in 19%, VLDL and LDL triglycerides in 23% and by various other combinations of raised LP triglyceride levels in 25% of cases. Hypercholesterolaemia was found in 41% of MI subjects. Of these, one-sixth had elevation of cholesterol levels, while five-sixths had combined hyperlipidaemia. The LP abnormalities underlying hypercholesterolaemia were increased of only VLDL cholesterol levels in 36%, only LDL cholesterol in 14% and both VLDL and LDL cholesterol in 50% of cases. The low HDL cholesterol values in comparison to controls were related to higher VLDL triglyceride values in MI patients, since HDL cholesterol fell significantly with increasing VLDL triglyceride levels. When HDL cholesterol was related to similar VLDL triglyceride levels, there were no major differences between controls and MI.