A prospective study of serum lipoproteins after coronary artery bypass surgery.
We examined the acute and long-term effects of coronary artery bypass (CABG) surgery on serum lipid, lipoprotein and apolipoprotein levels. One series of 34 patients having CABG surgery was studied pre-operatively and for six weeks afterwards, and another 22 patients were investigated before and two years after CABG surgery. None of the patients studied received any lipid-lowering drug therapy or specific dietary advice. In both groups, pre-operative serum lipoprotein (a) (Lp(a)) and serum triglyceride concentrations were raised and serum high-density lipoprotein (HDL) cholesterol and apolipoprotein AI (apo AI) were low compared to healthy people. Acutely, there were profound decreases of 40-60% in the serum levels of cholesterol (p < 0.001), low-density lipoprotein cholesterol (p < 0.05), triglycerides (p < 0.01), Lp(a) (p < 0.05) and apolipoprotein B (apo B) (p < 0.05). There was a small decrease in serum apo A1 (p < 0.05), and serum HDL cholesterol showed no change. All these variables regained their pre-operative values within six weeks. Two years postoperatively, serum Lpa was 40% less than its pre-operative concentration (p < 0.001) and HDL cholesterol had increased (p < 0.001). Triglyceride levels decreased (p < 0.02) when beta-blockade was withdrawn. The long-term decrease in Lp(a) following surgery is unlikely to be due either to stopping beta-blockers or to life-style changes. Myocardial ischaemia relieved by the operation may have been partially responsible for its previously raised concentration.
University Department of Medicine, Manchester Royal Infirmary, UK.
N
N
Shaukat
S S
SS
Ashraf
M I
MI
Mackness
A D
AD
Mbewu
D
D
Bhatnagar
P N
PN
Durrington
D000328:Adult; D000368:Aged; D001055:Apolipoproteins B / Q000032:analysis; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D001026:Coronary Artery Bypass; D003327:Coronary Disease / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D017270:Lipoprotein(a) / Q000097:blood; D008074:Lipoproteins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011446:Prospective Studies; D014280:Triglycerides / Q000097:blood
D001055:Apolipoproteins B; D008076:Cholesterol, HDL; D017270:Lipoprotein(a); D008074:Lipoproteins; D014280:Triglycerides; D002784:Cholesterol