SERUM-LIPIDS, LIPOPROTEIN(A) AND APO(A) ISOFORMS IN PATIENTS WITH ESTABLISHED CORONARY-ARTERY DISEASE AND THEIR RELATION TO DISEASE AND PROGNOSIS AFTER CORONARY-BYPASS SURGERY

Consecutive patients (n = 964) undergoing coronary angiography were st udied and compared with a random population sample regarding serum lip ids and lipoproteins with focus on lipoprotein(a) (Lp(a)) levels and a po(a) isoforms. The patients were also followed for 5 years after the angiography, and the progostic value of serum lipoproteins were analyz ed. The patients were divided in two groups: Group 1 (n = 814) consist ed of patients with angina pectoris and at least one coronary artery w ith 50% stenosis and group 2 (n = 150) patients with none of the coron ary arteries significantly obstructed (< 50%). As controls a random po pulation sample was selected (n = 197). Blood samples were collected b efore coronary angiography for determination of serum lipids, Lp(a) an d isoforms of apo(a). When group 1 and group 2 patients were compared, group 1 was found to have higher serum cholesterol, triglycerides, ap oB and Lp(a) as well as lower HDL and apoAI. When group 1 was compared with the random sample, after correction for age and sex, similar dif ferences were observed, except that the difference in Lp(a) was not si gnificant. The high Lp(a) levels among patients was found to be primar ily due to the female patients, where the difference compared to both group 2 and controls was highly significant (P = 0.007 and P = 0.001, respectively). There was a significant difference in the apo(a) isofor m distribution between group 1 patients and control subjects (P = 0.00 03), with a higher frequency of low molecular weight isoforms among pa tients. This was also significant for the male subgroup (P = 0.001). L p(a), LDL, total cholesterol, triglycerides, apoB, HDL and apoAI were significantly related to the number of major coronary arteries with > 50% stenosis. Mortality during follow-up was,in a univariate analysis, significantly correlated to several factors related to the degree of heart disease and to LDL (P = 0.02) and apoB (P < 0.01). Increased mor tality was, however, related to low levels of apoB and LDL. For cardia c mortality no significant correlation to lipoprotein variables were f ound. In conclusion established lipoprotein risk factors were more fre quent among patient with angina pectoris and verified coronary stenosi s. Furthermore high Lp(a) levels and a high frequency of low molecular weight isoforms of apo(a) were found in coronary patients. Higher Lp( a) levels were observed both for female and male patients, the differe nces were, however, significant only for the female patients. None of the lipoprotein variables could predict coronary death during the foll ow-up period. (C) 1998 Elsevier Science Ireland Ltd. All rights reserv ed.